19 files changed, 17534 insertions, 0 deletions

diff --git a/src/mod_pubsub_ng/Makefile.in b/src/mod_pubsub_ng/Makefile.in
new file mode 100644
index 000000000..9a114a1a3
--- /dev/null
+++ b/src/mod_pubsub_ng/Makefile.in
@@ -0,0 +1,62 @@
+CC = @CC@
+CFLAGS = @CFLAGS@
+CPPFLAGS = @CPPFLAGS@
+LDFLAGS = @LDFLAGS@
+LIBS = @LIBS@
+
+ERLANG_CFLAGS = @ERLANG_CFLAGS@
+ERLANG_LIBS = @ERLANG_LIBS@
+
+EFLAGS += -I ..
+EFLAGS += -pz ..
+
+# make debug=true to compile Erlang module with debug informations.
+ifdef debug
+	EFLAGS+=+debug_info
+endif
+
+OUTDIR = ..
+ERLBEHAVS = gen_pubsub_node.erl gen_pubsub_nodetree.erl
+SOURCES_ALL = $(wildcard *.erl)
+SOURCES = $(filter-out $(ERLBEHAVS),$(SOURCES_ALL))
+ERLBEHAVBEAMS = $(addprefix $(OUTDIR)/,$(ERLBEHAVS:.erl=.beam))
+BEAMS = $(addprefix $(OUTDIR)/,$(SOURCES:.erl=.beam))
+
+
+all: $(ERLBEHAVBEAMS) $(BEAMS)
+
+$(BEAMS): $(ERLBEHAVBEAMS)
+
+$(OUTDIR)/%.beam:       %.erl
+	@ERLC@ -W $(EFLAGS) -o $(OUTDIR) $<
+
+clean:
+	rm -f $(BEAMS)
+
+distclean: clean
+	rm -f Makefile
+
+
+
+TAGS:
+	etags *.erl
+
+
+DEVDOCDIR=../../doc/devdoc
+DDTDIR=..
+HTMLS = $(SOURCES:%.erl=../../doc/devdoc/%.html)
+ERLHTMLS = $(SOURCES:%.erl=../../doc/devdoc/%.erl.html)
+SVGS = $(SOURCES:%.erl=../../doc/devdoc/%.svg)
+
+devdoc: $(HTMLS) $(ERLHTMLS) $(SVGS)
+
+$(DEVDOCDIR)/%.erl.html: %.erl
+	@ERL@ -noshell -pa $(DEVDOCDIR) -run escobar_run file $< $(DDTDIR) -s init stop
+
+$(DEVDOCDIR)/%.html: %.erl
+	@ERL@ -noshell -run edoc_run file $< \
+	'[{dir,"$(DDTDIR)"},{packages,false},{todo,true},{private,true},{def,{vsn,"$(VSN)"}},{stylesheet,"process-one.css"},{overview,"overview.edoc"}]' -s init stop
+
+$(DEVDOCDIR)/%.svg: %.erl
+	@ERL@ -noshell -pa $(DEVDOCDIR) -run funrelg dir $< $(DDTDIR) -s init stop
+
diff --git a/src/mod_pubsub_ng/Makefile.win32 b/src/mod_pubsub_ng/Makefile.win32
new file mode 100644
index 000000000..6d5707b23
--- /dev/null
+++ b/src/mod_pubsub_ng/Makefile.win32
@@ -0,0 +1,88 @@
+
+include ..\Makefile.inc
+
+EFLAGS = -I .. -pz ..
+
+OUTDIR = ..
+BEAMS =  ..\exmpp_pubsub.beam ..\pubsub_disco.beam ..\mod_pubsub_dev.beam ..\pubsub_hooks.beam ..\mod_pubsub_odbc.beam ..\pubsub_index_dev.beam ..\pubsub_broadcast.beam ..\pubsub_options.beam ..\pubsub_core.beam ..\pubsub_parser.beam ..\pubsub_db.beam ..\xmpp_xdata.beam ..\pubsub_db_mnesia.beam
+
+
+ALL : $(BEAMS)
+
+CLEAN :
+	-@erase $(BEAMS)
+
+$(OUTDIR)\gen_pubsub_node.beam : gen_pubsub_node.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) gen_pubsub_node.erl
+
+$(OUTDIR)\gen_pubsub_nodetree.beam : gen_pubsub_nodetree.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) gen_pubsub_nodetree.erl
+
+$(OUTDIR)\mod_pubsub.beam : mod_pubsub.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) mod_pubsub.erl
+
+$(OUTDIR)\mod_pubsub_odbc.beam : mod_pubsub_odbc.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) mod_pubsub_odbc.erl
+
+$(OUTDIR)\node_buddy.beam : node_buddy.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) node_buddy.erl
+
+$(OUTDIR)\node_club.beam : node_club.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) node_club.erl
+
+$(OUTDIR)\node_dag.beam : node_dag.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) node_dag.erl
+
+$(OUTDIR)\node_dispatch.beam : node_dispatch.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) node_dispatch.erl
+
+$(OUTDIR)\node_flat.beam : node_flat.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) node_flat.erl
+
+$(OUTDIR)\node_flat_odbc.beam : node_flat_odbc.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) node_flat_odbc.erl
+
+$(OUTDIR)\node_hometree.beam : node_hometree.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) node_hometree.erl
+
+$(OUTDIR)\node_hometree_odbc.beam : node_hometree_odbc.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) node_hometree_odbc.erl
+
+$(OUTDIR)\node_mb.beam : node_mb.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) node_mb.erl
+
+$(OUTDIR)\node_pep.beam : node_pep.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) node_pep.erl
+
+$(OUTDIR)\node_pep_odbc.beam : node_pep_odbc.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) node_pep_odbc.erl
+
+$(OUTDIR)\node_private.beam : node_private.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) node_private.erl
+
+$(OUTDIR)\node_public.beam : node_public.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) node_public.erl
+
+$(OUTDIR)\nodetree_dag.beam : nodetree_dag.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) nodetree_dag.erl
+
+$(OUTDIR)\nodetree_tree.beam : nodetree_tree.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) nodetree_tree.erl
+
+$(OUTDIR)\nodetree_tree_odbc.beam : nodetree_tree_odbc.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) nodetree_tree_odbc.erl
+
+$(OUTDIR)\nodetree_virtual.beam : nodetree_virtual.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) nodetree_virtual.erl
+
+$(OUTDIR)\pubsub_db_odbc.beam : pubsub_db_odbc.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) pubsub_db_odbc.erl
+
+$(OUTDIR)\pubsub_index.beam : pubsub_index.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) pubsub_index.erl
+
+$(OUTDIR)\pubsub_subscription.beam : pubsub_subscription.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) pubsub_subscription.erl
+
+$(OUTDIR)\pubsub_subscription_odbc.beam : pubsub_subscription_odbc.erl
+	erlc -W $(EFLAGS) -o $(OUTDIR) pubsub_subscription_odbc.erl
diff --git a/src/mod_pubsub_ng/exmpp_pubsub.erl b/src/mod_pubsub_ng/exmpp_pubsub.erl
new file mode 100644
index 000000000..19bc1d76d
--- /dev/null
+++ b/src/mod_pubsub_ng/exmpp_pubsub.erl
@@ -0,0 +1,685 @@
+%%% ====================================================================
+%%% ``The contents of this file are subject to the Erlang Public License,
+%%% Version 1.1, (the "License"); you may not use this file except in
+%%% compliance with the License. You should have received a copy of the
+%%% Erlang Public License along with this software. If not, it can be
+%%% retrieved via the world wide web at http://www.erlang.org/.
+%%% 
+%%% Software distributed under the License is distributed on an "AS IS"
+%%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%%% the License for the specific language governing rights and limitations
+%%% under the License.
+%%% 
+%%% The Initial Developer of the Original Code is ProcessOne.
+%%% Portions created by ProcessOne are Copyright 2006-2011, ProcessOne
+%%% All Rights Reserved.''
+%%% This software is copyright 2006-2011, ProcessOne.
+%%%
+%%% @copyright 2006-2011 ProcessOne
+%%% @author Karim Gemayel <karim.gemayel@process-one.net>
+%%%   [http://www.process-one.net/]
+%%% @version {@vsn}, {@date} {@time}
+%%% @end
+%%% ====================================================================
+
+%%% @headerfile "pubsub_dev.hrl"
+
+-module(exmpp_pubsub).
+-author('karim.gemayel@process-one.net').
+
+-compile(export_all).
+
+-include("pubsub_dev.hrl").
+
+
+%% --------------------------------------------------------------------
+%% Documentation / type definitions.
+%% --------------------------------------------------------------------
+
+
+
+%-- Affiliations --%
+-export_type([
+  affiliation/0,
+  %%
+  affiliation_owner/0,
+  affiliation_publisher/0,
+  affiliation_publish_only/0,
+  affiliation_member/0,
+  affiliation_none/0,
+  affiliation_outcast/0
+]).
+
+%% @type affiliation_owner() = 'owner'.
+-type(affiliation_owner() :: 'owner').
+
+%% @type affiliation_publisher() = 'publisher'.
+-type(affiliation_publisher() :: 'publisher').
+
+%% @type affiliation_publish_only() = 'publish-only'.
+-type(affiliation_publish_only() :: 'publish-only').
+
+%% @type affiliation_member() = 'member'.
+-type(affiliation_member() :: 'member').
+
+%% @type affiliation_none() = 'none'.
+-type(affiliation_none() :: 'none').
+
+%% @type affiliation_outcast() = 'outcast'.
+-type(affiliation_outcast() :: 'outcast').
+
+%% @type affiliation() = Owner | Publisher | Publish_Only | Member | None | Outcast
+%%    Owner = exmpp_pubsub:affiliation_owner()
+%%    Publisher = exmpp_pubsub:affiliation_publisher()
+%%    Publish_Only = exmpp_pubsub:affiliation_publish_only()
+%%    Member = exmpp_pubsub:affiliation_member()
+%%    None = exmpp_pubsub:affiliation_none()
+%%    Outcast = exmpp_pubsub:affiliation_outcast().
+-type(affiliation() :: exmpp_pubsub:affiliation_owner()
+                     | exmpp_pubsub:affiliation_publisher()
+                     | exmpp_pubsub:affiliation_publish_only()
+                     | exmpp_pubsub:affiliation_member()
+                     | exmpp_pubsub:affiliation_none()
+                     | exmpp_pubsub:affiliation_outcast()
+).
+
+
+%%
+
+%-- Things identifiers --%
+-export_type([
+  index/0,
+  itemId/0,
+  itemIds/0,
+  level/0,
+  nodeId/0,
+  nodeIdx/0,
+  subId/0,
+  plugin/0
+]).
+
+%% @type index() = 'node'.
+-type(index() :: 'node' ).
+
+%% @type itemId() = binary().
+-type(itemId() :: binary()).
+
+%% @type itemIds() = [ItemId::exmpp_pubsub:itemId(),...].
+-type(itemIds() ::  [ItemId::exmpp_pubsub:itemId(),...]).
+
+%% @type level() = non_neg_integer().
+-type(level() :: non_neg_integer()).
+
+%% @type nodeId() = binary().
+-type(nodeId() :: binary()).
+
+%% @type nodeIdx() = non_neg_integer().
+-type(nodeIdx() :: non_neg_integer()).
+
+%% @type plugin() = module().
+-type(plugin() :: module()).
+
+%% @type subId() = binary().
+-type(subId() :: binary()).
+
+
+-export_type([
+  t_now/0
+]).
+
+%% Temporary -type, until calendar.erl -type is exported
+-type(t_now()
+  :: {MegaSec::non_neg_integer(),
+      Sec::non_neg_integer(),
+      MilliSec::non_neg_integer()}
+).
+
+
+%%
+-export_type([
+  feature/0,
+  features/0,
+  pubsub_feature/0,
+  pubsub_features/0
+]).
+
+-type(feature() :: binary()).
+
+-type(features() :: Features::[Feature::exmpp_pubsub:feature(),...]).
+
+-type(pubsub_feature() :: exmpp_pubsub:feature()).
+
+-type(pubsub_features() :: Pubsub_Features::[Pubsub_Feature::exmpp_pubsub:feature(),...]).
+
+%%
+
+%-- Payload types --%
+-export_type([
+    payload/0,
+    %%
+    payload_empty/0,
+    payload_full/0
+]).
+
+%% @type payload_empty() = [].
+-type(payload_empty() :: []).
+
+%% @type payload_full() = #xmlel{}.
+-type(payload_full() :: xmlel()).
+
+%% @type payload() = Empty_Payload | Full_Payload
+%%    Empty_Payload = exmpp_pubsub:payload_empty()
+%%    Full_Payload = exmpp_pubsub:payload_full().
+-type(payload() :: exmpp_pubsub:payload_empty()
+                 | exmpp_pubsub:payload_full()
+).
+
+
+%%
+
+%-- Pusbub Host --%
+-export_type([
+    host/0,
+    %%
+    host_pubsub/0,
+    host_pep/0
+]).
+
+%% @type host_pubsub() = xmpp_jid:domain_jid().
+%%    ```<<"pubsub.shakespeare.lit">>'''
+%%    Identifier type of the Pubsub service
+-type(host_pubsub() :: binary()).
+
+%% @type host_pep() = xmpp_jid:usr_contact_bare().
+%%    ```{<<"juliet">>, <<"capulet.lit">>, undefined}'''
+%%    Identifier type of the Pubsub-On-Jid service
+-type(host_pep() :: xmpp_jid:usr_contact_bare()).
+
+%% @type host() = Pubsub_Host | Pubsub_On_Jid_Host
+%%    Pubsub_Host = exmpp_pubsub:host_pubsub()
+%%    Pubsub_On_Jid_Host = exmpp_pubsub:host_pep().
+%%    Identifier types of the Pubsub and PEP (Pubsub-On-Jid) services
+%%    ```* Pubsub_Host : <<"pubsub.shakespeare.lit">>
+%%       * Pubsub_PEP  : {<<"juliet">>, <<"capulet.lit">>, undefined}'''
+-type(host() :: exmpp_pubsub:host_pubsub()
+              | exmpp_pubsub:host_pep()
+).
+
+
+%%
+
+%-- Subscription States --%
+-export_type([
+  subscription_state/0,
+  %%
+  subscription_state_none/0,
+  subscription_state_pending/0,
+  subscription_state_unconfigured/0,
+  subscription_state_subscribed/0
+]).
+
+%% @type subscription_state_none() = 'none'.
+-type(subscription_state_none() :: 'none').
+
+%% @type subscription_state_pending() = 'pending'.
+-type(subscription_state_pending() :: 'pending').
+
+%% @type subscription_state_unconfigured() = 'unconfigured'.
+-type(subscription_state_unconfigured() :: 'unconfigured').
+
+%% @type subscription_state_subscribed() = 'subscribed'.
+-type(subscription_state_subscribed() :: 'subscribed').
+
+%% @type subscription_state() = None | Pending | Unconfigured | Subscribed
+%%    None = exmpp_pubsub:subscription_state_none()
+%%    Pending = exmpp_pubsub:subscription_state_pending()
+%%    Unconfigured = exmpp_pubsub:subscription_state_unconfigured()
+%%    Subscribed = exmpp_pubsub:subscription_state_subscribed()
+-type(subscription_state() :: exmpp_pubsub:subscription_state_pending()
+                            | exmpp_pubsub:subscription_state_unconfigured()
+                            | exmpp_pubsub:subscription_state_subscribed()
+).
+
+%%
+
+%-- Subscription -- %%
+-export_type([
+  subscriptions/0,
+  subscription/0,
+  %%
+  subscription_subscribed/0,
+  subscription_unconfigured/0,
+  subscription_pending/0
+]).
+
+-type(subscription_subscribed()
+  :: {Subscription_State   :: exmpp_pubsub:subscription_state_subscribed(),
+      SubId                :: exmpp_pubsub:subId(),
+      Resource             :: undefined | xmpp_jid:resource_jid() | {'caps', xmpp_jid:resource_jid()},
+      Subscription_Options :: [] | pubsub_options:options_subscription()}
+).
+
+-type(subscription_unconfigured()
+  :: {Subscription_State   :: exmpp_pubsub:subscription_state_unconfigured(),
+      SubId                :: exmpp_pubsub:subId(),
+      Resource             :: undefined | xmpp_jid:resource_jid() | {'caps', xmpp_jid:resource_jid()},
+      Subscription_Options :: []}
+).
+
+-type(subscription_pending()
+  :: {Subscription_State   :: exmpp_pubsub:subscription_state_pending(),
+      SubId                :: exmpp_pubsub:subId(),
+      Resource             :: undefined | xmpp_jid:resource_jid() | {'caps', xmpp_jid:resource_jid()},
+      Subscription_Options :: []}
+).
+
+-type(subscription()
+  :: {Subscription_State   :: exmpp_pubsub:subscription_state(),
+      SubId                :: exmpp_pubsub:subId(),
+      Resource             :: undefined | xmpp_jid:resource_jid() | {'caps', xmpp_jid:resource_jid()},
+      Subscription_Options :: [] | pubsub_options:options_subscription()}
+%%  :: exmpp_pubsub:subscription_subscribed()
+%%   | exmpp_pubsub:subscription_pending()
+%%   | exmpp_pubsub:subscription_unconfigured()
+).
+
+-type(subscriptions()
+    :: [exmpp_pubsub:subscription(),...]
+%%  :: [exmpp_pubsub:subscription_subscribed(),...]
+%%   | [exmpp_pubsub:subscription_unconfigured(),...]
+%%   | [exmpp_pubsub:subscription_pending(),...]
+).
+
+%% TODO : commented -type unions return the following dialyzer error (bug ?) :
+%% ...
+%%  Adding information from /home/meta/otp-exmpp.plt to ejabberd.plt...
+%%=ERROR REPORT==== 29-Jul-2011::15:14:42 ===
+%Error in process <0.2604.0> with exit value: {function_clause,[{erl_types,inf_tuples_in_sets,4},{erl_types,inf_tuple_sets,4},{erl_types,inf_tuple_sets,3},{erl_types,t_inf,3},{erl_types,t_inf_lists_strict,4},{erl_types,t_inf,3},{dialyzer_typesig,solve_one_c... 
+%%
+%%
+%%dialyzer: Analysis failed with error: {function_clause,[{erl_types,inf_tuples_in_sets,4},
+%%                  {erl_types,inf_tuple_sets,4},
+%%                  {erl_types,inf_tuple_sets,3},
+%%                  {erl_types,t_inf,3},
+%%                  {erl_types,t_inf_lists_strict,4},
+%%                  {erl_types,t_inf,3},
+%%                  {dialyzer_typesig,solve_one_c,...},
+%%                  {dialyzer_typesig,...}]}
+%%Last messages in the log cache:
+%%  Typesig analysis for SCC: [{ejabberd_web_admin,make_xhtml,5}]
+%%  Typesig analysis for SCC: [{ejabberd_web_admin,make_xhtml,4}]
+%%  Typesig analysis for SCC: [{ejabberd_web_admin,process_admin,2}]
+%%  Typesig analysis for SCC: [{ejabberd_web_admin,process,2}]
+%%  Typesig analysis for SCC: [{mod_stats,get_local_stat,3}]
+%%  Typesig analysis for SCC: [{mod_stats,get_local_stats,3}]
+%%  Typesig analysis for SCC: [{mod_stats,process_local_iq,3}]
+%%  Typesig analysis for SCC: [{mod_register_web,send_registration_notifications,2}]
+%%  Typesig analysis for SCC: [{mod_register_web,process,2}]
+%%  Typesig analysis for SCC: [{pubsub_db,create_node,5}]
+
+%%
+
+
+%% Pubsub #xmlel{} templates
+
+
+%% --------------------------------------------------------------------
+%% Functions.
+%% --------------------------------------------------------------------
+
+
+
+
+%% @spec nodeId() -> NodeId::exmpp_pubsub:nodeId()
+-spec(nodeId/0 :: () -> NodeId::exmpp_pubsub:nodeId()).
+
+nodeId() ->
+    randoms:get_string().
+
+%% @spec subId() -> SubId::exmpp_pubsub:subId()
+-spec(subId/0 :: () -> SubId::exmpp_pubsub:subId()).
+
+subId() ->
+    {T1, T2, T3} = now(),
+    list_to_binary(lists:flatten(io_lib:fwrite("~.16B~.16B~.16B", [T1, T2, T3]))).
+
+%% @spec itemId() -> ItemId::exmpp_pubsub:itemId()
+-spec(itemId/0 :: () -> ItemId::exmpp_pubsub:itemId()).
+
+itemId() ->
+    {T1, T2, T3} = now(),
+    list_to_binary(lists:flatten(io_lib:fwrite("~.16B~.16B~.16B", [T1, T2, T3]))).
+
+id() ->
+    {T1, T2, T3} = now(),
+    list_to_binary(lists:flatten(io_lib:fwrite("~.16B~.16B~.16B", [T1, T2, T3]))).
+
+
+
+%%
+-spec(subscription_subscribed/2 ::
+(
+  Resource             :: undefined
+                        | xmpp_jid:resource_jid()
+                        | {'caps', xmpp_jid:resource_jid()},
+  Subscription_Options :: [] | pubsub_options:options_subscription())
+    -> Subscription_Subscribed::exmpp_pubsub:subscription_subscribed()
+).
+
+subscription_subscribed(Resource, Subscription_Options) ->
+    {'subscribed', subId(), Resource, Subscription_Options}.
+
+%%
+-spec(subscription_pending/2 ::
+(
+  Resource             :: undefined
+                        | xmpp_jid:resource_jid()
+                        | {'caps', xmpp_jid:resource_jid()},
+  Subscription_Options :: [] | pubsub_options:options_subscription())
+    -> Subscription_Pending::exmpp_pubsub:subscription_pending()
+).
+
+subscription_pending(Resource, Subscription_Options) ->
+    {'pending', subId(), Resource, Subscription_Options}.
+
+
+
+%% Pubsub Xmlel templates
+
+xmlcdata(CData) ->
+    {xmlcdata, CData}.
+
+xmlattr(Name, Value) ->
+    {Name, Value}.
+
+
+xmlel('disco#info', Name, Attrs, Children) ->
+    xmlel(?NS_DISCO_INFO, Name, Attrs, Children);
+xmlel('disco#items', Name, Attrs, Children) ->
+    xmlel(?NS_DISCO_ITEMS, Name, Attrs, Children);
+xmlel('jabber:client', Name, Attrs, Children) ->
+    xmlel(?NS_JABBER_CLIENT, Name, Attrs, Children);
+xmlel('pubsub', Name, Attrs, Children) ->
+    xmlel(?NS_PUBSUB, Name, Attrs, Children);
+xmlel('pubsub#event', Name, Attrs, Children) ->
+    xmlel(?NS_PUBSUB_EVENT, Name, Attrs, Children);
+xmlel('pubsub#owner', Name, Attrs, Children) ->
+    xmlel(?NS_PUBSUB_OWNER, Name, Attrs, Children);
+xmlel('shim', Name, Attrs, Children) ->
+    xmlel(?NS_SHIM, Name, Attrs, Children);
+xmlel(NS, Name, Attrs, Children) ->
+    #xmlel{name = Name, attrs = [{<<"xmlns">>, NS} | Attrs], children = Children}.
+%%
+xmlattr_affiliation(Affiliation) ->
+    xmlattr(<<"affiliation">>, list_to_binary(atom_to_list(Affiliation))).
+%%
+xmlattr_category(Category) ->
+    xmlattr(<<"category">>, Category).
+%%
+xmlattr_id(ItemId) ->
+    xmlattr(<<"id">>, ItemId).
+%%
+xmlattr_jid(Jid) ->
+    xmlattr(<<"jid">>, Jid).
+%%
+xmlattr_name(Name) ->
+    xmlattr(<<"name">>, Name).
+%%
+xmlattr_node(NodeId) ->
+    xmlattr(<<"node">>, NodeId).
+%%
+xmlattr_publisher(Publisher) ->
+    xmlattr(<<"publisher">>, Publisher).
+%%
+xmlattr_subid(SubId) ->
+    xmlattr(<<"subid">>, SubId).
+%%
+xmlattr_subscription(Subscription_State) ->
+    xmlattr(<<"subscription">>, list_to_binary(atom_to_list(Subscription_State))).
+%%
+xmlattr_type(Type) when is_atom(Type)->
+    xmlattr(<<"type">>, list_to_binary(atom_to_list(Type)));
+%%
+xmlattr_type(Type) ->
+    xmlattr(<<"type">>, Type).
+%%
+xmlattr_uri(URI) ->
+    xmlattr(<<"uri">>, URI).
+%%
+xmlattr_var(Var) ->
+    xmlattr(<<"var">>, Var).
+
+%%
+xmlel_affiliation('pubsub', NodeId, Affiliation) ->
+    xmlel('pubsub', <<"affiliation">>,
+        [xmlattr_node(NodeId),
+         xmlattr_affiliation(Affiliation)],
+        []);
+xmlel_affiliation('pubsub#owner', Jid, Affiliation) ->
+    xmlel('pubsub#owner', <<"affiliation">>,
+        [xmlattr_jid(Jid),
+         xmlattr_affiliation(Affiliation)],
+        []). 
+%%
+xmlel_affiliations('pubsub', Xmlels) ->
+    xmlel('pubsub', <<"affiliations">>, [], Xmlels).
+
+xmlel_affiliations('pubsub#owner', NodeId, Xmlels) ->
+    xmlel('pubsub#owner', <<"affiliations">>, [xmlattr_node(NodeId)], Xmlels).
+%%
+xmlel_create(NodeId) ->
+    xmlel('pubsub', <<"create">>, [xmlattr_node(NodeId)], []).
+
+%%
+xmlel_configure('pubsub#owner', NodeId, Xmlels) ->
+    xmlel('pubsub#owner', <<"configure">>, [xmlattr_node(NodeId)], Xmlels).
+
+%%
+xmlel_default('pubsub', Xmlels) ->
+    xmlel('pubsub', <<"default">>, [], Xmlels);
+%%
+xmlel_default('pubsub#owner', Xmlels) ->
+    xmlel('pubsub#owner', <<"default">>, [], Xmlels).
+
+%%
+xmlel_default('pubsub', NodeId, Xmlels) ->
+    xmlel('pubsub', <<"default">>, [xmlattr_node(NodeId)], Xmlels).
+
+%%
+xmlel_delete(NodeId, RedirectURI) ->
+    xmlel('pubsub#event', <<"delete">>,
+        [xmlattr_node(NodeId)],
+        case RedirectURI of
+            undefined    -> [];
+            _RedirectURI -> [xmlel_redirect(RedirectURI)]
+        end).
+%%
+xmlel_event(Xmlels) ->
+    xmlel('pubsub#event', <<"event">>, [], Xmlels).
+%%
+xmlel_feature('disco#info', Feature) ->
+    xmlel('disco#info', <<"feature">>, [xmlattr_var(Feature)], []).
+%%
+xmlel_header(SubId) ->
+    xmlel('shim', <<"header">>, [xmlattr_name(<<"SubID">>)], [xmlcdata(SubId)]).
+%%
+xmlel_headers(Xmlels_Header) ->
+    xmlel('shim', <<"headers">>, [], Xmlels_Header).
+
+
+xmlel_identity('disco#info', Category, Type, Name) ->
+    xmlel('disco#info', <<"identity">>,
+        case Name of
+            undefined ->
+                [xmlattr_category(Category),
+                 xmlattr_type(Type)];
+            _ ->
+                [xmlattr_category(Category),
+                 xmlattr_name(Name),
+                 xmlattr_type(Type)]
+        end,
+        []).
+
+%%
+xmlel_item('pubsub', ItemId) ->
+    xmlel('pubsub', <<"item">>, [xmlattr_id(ItemId)], []).
+
+%%
+xmlel_item('disco#items', ItemId, Jid) ->
+    xmlel('disco#items', <<"item">>,
+        [xmlattr_name(ItemId),
+         xmlattr_jid(Jid)],
+        []);
+xmlel_item('pubsub', ItemId, Payload) ->
+    xmlel('pubsub', <<"item">>, [xmlattr_id(ItemId)],
+        case Payload of
+            []       -> [];
+            _Payload -> [Payload]
+        end).
+
+xmlel_item('disco#items', NodeId, Jid, Name) ->
+    xmlel('disco#items', <<"item">>,
+        case Name of
+            undefined ->
+                [xmlattr_jid(Jid),
+                 xmlattr_node(NodeId)];
+            _ ->
+                [xmlattr_jid(Jid),
+                 xmlattr_node(NodeId),
+                 xmlattr_name(Name)]
+        end,
+        []);
+%%
+xmlel_item('pubsub#event', ItemId, Publisher, Payload) ->
+    xmlel('pubsub#event', <<"item">>,
+        case Publisher of
+            undefined ->
+                [xmlattr_id(ItemId)];
+            _Publisher ->
+                [xmlattr_id(ItemId),
+                 xmlattr_publisher(Publisher)]
+        end,
+        case Payload of
+            []       -> [];
+            _Payload -> [Payload]
+        end).
+%%
+xmlel_items('pubsub', NodeId, Xmlels) ->
+    xmlel('pubsub', <<"items">>, [xmlattr_node(NodeId)], Xmlels);
+%%
+xmlel_items('pubsub#event', undefined = _NodeId, Xmlels) ->
+    xmlel('pubsub#event', <<"items">>, [], Xmlels);
+%%
+xmlel_items('pubsub#event', NodeId, Xmlels) ->
+    xmlel('pubsub#event', <<"items">>, [xmlattr_node(NodeId)], Xmlels).
+%%
+xmlel_items('pubsub#event', NodeId, undefined = _ItemId, _Publisher, _Payload) ->
+    xmlel('pubsub#event', <<"items">>, [xmlattr_node(NodeId)], []);
+xmlel_items('pubsub#event', NodeId, ItemId, Publisher, Payload) ->
+    xmlel('pubsub#event', <<"items">>,
+        [xmlattr_node(NodeId)],
+        [xmlel_item('pubsub#event', ItemId, Publisher, Payload)]).
+%%
+xmlel_message(undefined = _Type, Xmlels) ->
+    xmlel_message('normal', Xmlels);
+xmlel_message(Type, Xmlels) ->
+    xmlel('jabber:client', <<"message">>,
+        [xmlattr_type(Type),
+         xmlattr_id(_Id = id())],
+        Xmlels).
+%%
+xmlel_options('pubsub', NodeId, Jid, SubId, Xmlels) ->
+    xmlel('pubsub', <<"options">>,
+        case SubId of
+            undefined ->
+                [xmlattr_node(NodeId),
+                 xmlattr_jid(Jid)];
+            _ ->
+                [xmlattr_node(NodeId),
+                 xmlattr_jid(Jid),
+                 xmlattr_subid(SubId)]
+        end,
+        Xmlels).
+%%
+xmlel_publish('pubsub', NodeId, Xmlels) ->
+    xmlel('pubsub', <<"publish">>, [xmlattr_node(NodeId)], Xmlels).
+%%
+xmlel_purge(NodeId) ->
+    xmlel('pubsub#event', <<"purge">>, [xmlattr_node(NodeId)], []).
+
+%%
+xmlel_query('disco#info', Xmlels) ->
+    xmlel('disco#info', <<"query">>, [], Xmlels);
+%%
+xmlel_query('disco#items', Xmlels) ->
+    xmlel('disco#items', <<"query">>, [], Xmlels).
+
+%%
+xmlel_query('disco#info', NodeId, Xmlels) ->
+    xmlel('disco#info', <<"query">>, [xmlattr_node(NodeId)], Xmlels);
+xmlel_query('disco#items', NodeId, Xmlels) ->
+    xmlel('disco#items', 'query', [xmlattr_node(NodeId)], Xmlels).
+
+%%
+xmlel_redirect(RedirectURI) ->
+    xmlel('pubsub#event', <<"redirect">>, [xmlattr_uri(RedirectURI)], []).
+%%
+xmlel_retract(undefined = _ItemId) ->
+    xmlel('pubsub#event', <<"retract">>, [], []);
+xmlel_retract(ItemId) ->
+    xmlel('pubsub#event', <<"retract">>, [xmlattr_id(ItemId)], []).
+%%
+xmlel_subscription('pubsub', NodeId, Jid, SubId, Subscription_State) ->
+    xmlel('pubsub', <<"subscription">>,
+        [xmlattr_node(NodeId),
+         xmlattr_jid(Jid),
+         xmlattr_subid(SubId),
+         xmlattr_subscription(Subscription_State)],
+        []);
+xmlel_subscription('pubsub#event', NodeId, Jid, SubId, Subscription_State) ->
+    xmlel('pubsub#event', <<"subscription">>,
+        case SubId of
+            undefined ->
+                [xmlattr_node(NodeId),
+                 xmlattr_jid(Jid),
+                 xmlattr_subscription(Subscription_State)];
+            _SubId ->
+                [xmlattr_node(NodeId),
+                 xmlattr_jid(Jid),
+                 xmlattr_subid(SubId),
+                 xmlattr_subscription(Subscription_State)]
+        end,
+        []).
+%%
+xmlel_subscription('pubsub#owner', Jid, SubId, Subscription_State) ->
+    xmlel('pubsub#owner', <<"subscription">>,
+        case SubId of
+            undefined ->
+                [xmlattr_jid(Jid),
+                 xmlattr_subscription(Subscription_State)];
+            _SubId ->
+                [xmlattr_jid(Jid),
+                 xmlattr_subid(SubId),
+                 xmlattr_subscription(Subscription_State)]
+        end,
+        []).
+%%
+xmlel_subscriptions('pubsub', Xmlels) ->
+    xmlel('pubsub', <<"subscriptions">>, [], Xmlels).
+
+xmlel_subscriptions('pubsub#owner', NodeId, Xmlels) ->
+    xmlel('pubsub#owner', <<"subscriptions">>, [xmlattr_node(NodeId)], Xmlels).
+%%
+xmlel_publish(NodeId, undefined = _ItemId) ->
+    xmlel('pubsub', <<"publish">>, [xmlattr_node(NodeId)], []);
+xmlel_publish(NodeId, ItemId) ->
+    xmlel('pubsub', <<"publish">>,
+        [xmlattr_node(NodeId)],
+        [xmlel_item('pubsub', ItemId)]).
+%%
+xmlel_pubsub('pubsub', Children) ->
+    xmlel('pubsub', <<"pubsub">>, [], Children);
+%%
+xmlel_pubsub('pubsub#owner', Children) ->
+    xmlel('pubsub#owner', <<"pubsub">>, [], Children).
+
diff --git a/src/mod_pubsub_ng/mod_pubsub_dev.erl b/src/mod_pubsub_ng/mod_pubsub_dev.erl
new file mode 100644
index 000000000..9faca6552
--- /dev/null
+++ b/src/mod_pubsub_ng/mod_pubsub_dev.erl
@@ -0,0 +1,863 @@
+%%% ====================================================================
+%%% ``The contents of this file are subject to the Erlang Public License,
+%%% Version 1.1, (the "License"); you may not use this file except in
+%%% compliance with the License. You should have received a copy of the
+%%% Erlang Public License along with this software. If not, it can be
+%%% retrieved via the world wide web at http://www.erlang.org/.
+%%% 
+%%% Software distributed under the License is distributed on an "AS IS"
+%%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%%% the License for the specific language governing rights and limitations
+%%% under the License.
+%%% 
+%%% The Initial Developer of the Original Code is ProcessOne.
+%%% Portions created by ProcessOne are Copyright 2006-2011, ProcessOne
+%%% All Rights Reserved.''
+%%% This software is copyright 2006-2011, ProcessOne.
+%%%
+%%% @copyright 2006-2011 ProcessOne
+%%% @author Christophe Romain <christophe.romain@process-one.net>
+%%%   [http://www.process-one.net/]
+%%% @author Karim Gemayel <karim.gemayel@process-one.net>
+%%%   [http://www.process-one.net/]
+%%% @version {@vsn}, {@date} {@time}
+%%% @end
+%%% ====================================================================
+
+%%% @headerfile "pubsub_dev.hrl"
+
+-module(mod_pubsub_dev).
+-author('christophe.romain@process-one.net').
+-author('karim.gemayel@process-one.net').
+-version('1.13-0').
+
+-behaviour(gen_server).
+-behaviour(gen_mod).
+
+-include("pubsub_dev.hrl").
+-include("pubsub_api.hrl").
+
+-compile(export_all).
+%%% Export Functions
+
+%% API and gen_server callbacks
+-export([
+  start_link/2,
+  start/2,
+  stop/1,
+  init/1,
+  handle_call/3,
+  handle_cast/2,
+  handle_info/2,
+  terminate/2,
+  code_change/3
+]).
+
+%%
+-export_type([
+  resource_show/0,
+  presence_cache/0
+]).
+
+-type(resource_show()
+  :: {Resource :: xmpp_jid:resource_jid(),
+      Show     :: 'away' | 'chat' | 'dnd' | 'online' | 'xa' }
+).
+
+-type(presence_cache() :: [Resource_Show::resource_show()]).
+
+%%
+-export_type([
+  resource_subids/0,
+  resources_subids/0
+]).
+
+-type(resource_subids()
+  :: {Resource :: xmpp_jid:resource_jid(),
+      SubIds   :: [SubId::exmpp_pubsub:subId(),...]}
+).
+
+-type(resources_subids() :: [Resource_SubIds::resource_subids(),...]).
+
+%%%
+-export_type([
+  entity/0,
+  n0de/0,
+  cache/0,
+  subids/0,
+  event/0
+]).
+
+-type(entity() :: #entity{}).
+%  id            :: xmpp_jid:usr_bare(),
+%  affiliation   :: 'member' | 'owner' | 'publisher',
+%  subscriptions :: []%[exmpp_pubsub:subscription(),...]
+%}).
+
+%%%
+-type(n0de() :: #node{}).
+%  id                      :: exmpp_pubsub:nodeId(),
+%  owners                  :: [Node_Owner::xmpp_jid:usr_bare(),...],
+%  access_model            :: pubsub_options:access_model(),
+%  itemreply               :: 'owner' | 'publisher',
+%  notification_type       :: 'headline' | 'normal',
+%  presence_based_delivery :: boolean(),
+%  rosters_groups_allowed  :: [] | pubsub_options:rosters_groups_allowed()
+%}).
+
+%%%
+-type(cache() :: #cache{}).
+%  presence               :: undefined | mod_pubsub_dev:presence_cache(),
+%  presence_subscriptions :: undefined | boolean(),
+%  rosters_groups         :: undefined | boolean()
+%}).
+
+%%%
+-type(subids() :: #subids{}).
+%  presence    :: undefined | [] | mod_pubsub_dev:resources_subids(),
+%  no_presence :: undefined | [] | mod_pubsub_dev:resources_subids()
+%}).
+
+%%
+-type(event() :: #event{
+%  host      :: xmpp_jid:raw_jid_component_bare(),
+%  component :: xmpp_jid:component_bare(),
+%  entity    :: mod_pubsub_dev:entity(),
+%  node      :: mod_pubsub_dev:n0de(),
+%  cache     :: mod_pubsub_dev:cache(),
+%  subids    :: mod_pubsub_dev:subids()
+}).
+
+%%%
+-export_type([
+  item/0,
+  published_item/0,
+  retracted_item/0
+]).
+
+-type(published_item() :: #item{
+  access_model            :: undefined | pubsub_options:access_model(),
+  presence_based_delivery :: undefined | boolean(),
+  rosters_groups_allowed  :: [] | pubsub_options:rosters_groups_allowed(),
+  stanza                  :: xmlel()
+}).
+
+-type(retracted_item() :: #item{
+  access_model            :: undefined | pubsub_options:access_model(),
+  presence_based_delivery :: undefined | boolean(),
+  rosters_groups_allowed  :: [] | pubsub_options:rosters_groups_allowed(),
+  stanza                  :: xmlel()
+}).
+
+-type(item() :: published_item() | retracted_item()).
+
+
+%%
+
+-export_type([
+  pubsub_itemId/0,
+  pubsub_nodeId/0,
+  pubsub_stateId/0,
+  item_owners/0,
+  node_owners/0,
+  item_creation/0,
+  item_modification/0,
+  node_creation/0
+]).
+
+-type(pubsub_itemId()
+  :: {ItemId::exmpp_pubsub:itemId(), NodeIdx::exmpp_pubsub:nodeIdx()}
+).
+
+-type(pubsub_nodeId()
+  :: {Pubsub_Host :: exmpp_pubsub:host(), NodeId :: exmpp_pubsub:nodeId()}
+).
+
+-type(pubsub_stateId()
+  :: {Entity::xmpp_jid:usr_bare(), NodeIdx::exmpp_pubsub:nodeIdx()}
+).
+
+-type(item_owners() :: [Entity::xmpp_jid:usr_bare(),...]).
+-type(node_owners() :: [Entity::xmpp_jid:usr_bare(),...]).
+
+-type(item_creation()
+  :: {DateTime::erlang:timestamp(), Entity::xmpp_jid:usr_entity()}
+).
+
+-type(item_modification()
+  :: {DateTime::erlang:timestamp(), Entity::xmpp_jid:usr_entity()}
+).
+
+-type(node_creation()
+  :: {DateTime::erlang:timestamp(), Entity::xmpp_jid:usr_entity()}
+).
+
+
+
+%%
+-export_type([
+  pubsub_state/0,
+  pubsub_states/0,
+  %
+  pubsub_state_owner/0,
+  pubsub_state_publisher/0,
+  pubsub_state_publish_only/0,
+  pubsub_state_member/0,
+  pubsub_state_none/0,
+  pubsub_state_outcast/0
+]).
+
+-type(pubsub_state_owner()
+  :: #pubsub_state_dev{
+         id            :: mod_pubsub_dev:pubsub_stateId(),
+         nodeidx       :: exmpp_pubsub:nodeIdx(),
+         affiliation   :: 'owner',
+         access        :: undefined | 'presence' | 'roster',
+         %subscriptions :: [exmpp_pubsub:subscription_subscribed()  |
+         %                  exmpp_pubsub:subscription_unconfigured()],
+         subscriptions :: [exmpp_pubsub:subscription()],
+         itemids       :: [] | exmpp_pubsub:itemIds()
+     }
+).
+
+%%
+-type(pubsub_state_publisher()
+  :: #pubsub_state_dev{
+         id            :: mod_pubsub_dev:pubsub_stateId(),
+         nodeidx       :: exmpp_pubsub:nodeIdx(),
+         affiliation   :: 'publisher',
+         access        :: undefined | 'presence' | 'roster',
+         %subscriptions :: [exmpp_pubsub:subscription_subscribed()  |
+         %                  exmpp_pubsub:subscription_unconfigured()],
+         subscriptions :: [exmpp_pubsub:subscription()],
+         itemids       :: [] | exmpp_pubsub:itemIds()
+     }
+).
+
+%%
+-type(pubsub_state_publish_only()
+  :: #pubsub_state_dev{
+         id            :: mod_pubsub_dev:pubsub_stateId(),
+         nodeidx       :: exmpp_pubsub:nodeIdx(),
+         affiliation   :: 'publish-only',
+         access        :: undefined | 'presence' | 'roster',
+         subscriptions :: [],
+         itemids       :: [] | exmpp_pubsub:itemIds()
+     }
+).
+
+%%
+-type(pubsub_state_member()
+  :: #pubsub_state_dev{
+         id            :: mod_pubsub_dev:pubsub_stateId(),
+         nodeidx       :: exmpp_pubsub:nodeIdx(),
+         affiliation   :: 'member',
+         access        :: undefined | 'pending' | 'presence' | 'roster',
+         subscriptions :: [],
+         itemids       :: [] | exmpp_pubsub:itemIds()
+     }
+  %%
+   | #pubsub_state_dev{
+         id            :: mod_pubsub_dev:pubsub_stateId(),
+         nodeidx       :: exmpp_pubsub:nodeIdx(),
+         affiliation   :: 'member',
+         access        :: undefined | 'pending' | 'presence' | 'roster',
+         %subscriptions :: [exmpp_pubsub:subscription_pending(),...],
+         subscriptions :: [exmpp_pubsub:subscription()],
+         itemids       :: [] | exmpp_pubsub:itemIds()
+     }
+  %%
+   | #pubsub_state_dev{
+         id            :: mod_pubsub_dev:pubsub_stateId(),
+         nodeidx       :: exmpp_pubsub:nodeIdx(),
+         affiliation   :: 'member',
+         subscriptions :: [exmpp_pubsub:subscription()],
+         %subscriptions :: [exmpp_pubsub:subscription_pending()     |
+         %                  exmpp_pubsub:subscription_subscribed()  |
+         %                  exmpp_pubsub:subscription_unconfigured()],
+         itemids       :: [] | exmpp_pubsub:itemIds()
+     }
+).
+
+%%
+-type(pubsub_state_none()
+  :: #pubsub_state_dev{
+         id            :: mod_pubsub_dev:pubsub_stateId(),
+         nodeidx       :: exmpp_pubsub:nodeIdx(),
+         affiliation   :: 'none',
+         access        :: undefined | 'presence' | 'roster',
+         subscriptions :: [],
+         itemids       :: []
+     }
+  %%
+   | #pubsub_state_dev{
+         id            :: mod_pubsub_dev:pubsub_stateId(),
+         nodeidx       :: exmpp_pubsub:nodeIdx(),
+         affiliation   :: 'none',
+         access        :: undefined | 'presence' | 'roster',
+         subscriptions :: [],
+         itemids       :: exmpp_pubsub:itemIds()
+     }
+  %%
+   | #pubsub_state_dev{
+         id            :: mod_pubsub_dev:pubsub_stateId(),
+         nodeidx       :: exmpp_pubsub:nodeIdx(),
+         affiliation   :: 'none',
+         access        :: undefined | 'presence' | 'roster',
+         subscriptions :: [],
+         itemids       :: exmpp_pubsub:itemIds()
+     }
+).
+
+%%
+-type(pubsub_state_outcast()
+  :: #pubsub_state_dev{
+         id            :: mod_pubsub_dev:pubsub_stateId(),
+         nodeidx       :: exmpp_pubsub:nodeIdx(),
+         affiliation   :: 'outcast',
+         access        :: undefined | 'presence' | 'roster',
+         subscriptions :: [exmpp_pubsub:subscription()],
+         %subscriptions :: [exmpp_pubsub:subscription_pending()     |
+         %                  exmpp_pubsub:subscription_subscribed()  |
+         %                  exmpp_pubsub:subscription_unconfigured()],
+         itemids       :: [] | exmpp_pubsub:itemIds()
+     }
+).
+
+
+%%
+-type(pubsub_state() :: mod_pubsub_dev:pubsub_state_owner()
+                      | mod_pubsub_dev:pubsub_state_publisher()
+                      | mod_pubsub_dev:pubsub_state_publish_only()
+                      | mod_pubsub_dev:pubsub_state_member()
+                      | mod_pubsub_dev:pubsub_state_none()
+                      | mod_pubsub_dev:pubsub_state_outcast()
+).
+
+-type(pubsub_states() :: [Pubsub_State::mod_pubsub_dev:pubsub_state(),...]).
+
+
+%%
+-export_type([
+  pubsub_node/0,
+  pubsub_nodes/0
+]).
+
+-type(pubsub_node()
+  :: #pubsub_node_dev{
+         id       :: mod_pubsub_dev:pubsub_nodeId(),
+         idx      :: exmpp_pubsub:nodeIdx(),
+         creation :: mod_pubsub_dev:node_creation(),
+         level    :: exmpp_pubsub:level(),
+         owners   :: mod_pubsub_dev:node_owners(),
+         itemids  :: [] | exmpp_pubsub:itemIds(),
+         options  :: pubsub_options:options_node()
+    }
+).
+
+-type(pubsub_nodes() :: [Pubsub_Node::mod_pubsub_dev:pubsub_node(),...]).
+
+
+%%
+-export_type([
+  pubsub_item/0,
+  pubsub_items/0
+]).
+
+-type(pubsub_item()
+  :: #pubsub_item_dev{
+         id           :: mod_pubsub_dev:pubsub_itemId(),
+         nodeidx      :: exmpp_pubsub:nodeIdx(),
+         owners       :: mod_pubsub_dev:item_owners(),
+         creation     :: mod_pubsub_dev:item_creation(),
+         modification :: mod_pubsub_dev:item_modification(),
+         payload      :: exmpp_pubsub:payload(),
+         options      :: [] | pubsub_options:options_item()
+    }
+).
+
+-type(pubsub_items() :: [Pubsub_Item::mod_pubsub_dev:pubsub_item(),...]).
+
+%%
+-export_type([
+  pubsub_last_item/0
+]).
+
+-type(pubsub_last_item()
+  :: #pubsub_last_item_dev{
+         nodeidx  :: exmpp_pubsub:nodeIdx(),
+         id       :: exmpp_pubsub:itemId(),
+         owners   :: mod_pubsub_dev:item_owners(),
+         creation :: mod_pubsub_dev:item_creation(),
+         payload  :: exmpp_pubsub:payload(),
+         options  :: [] | pubsub_options:options_item()
+     }
+).
+
+%%
+-export_type([
+  pubsub_subscription_pending/0
+]).
+
+-type(pubsub_subscription_pending()
+  :: #pubsub_subscription_pending{
+         id      :: {Entity::xmpp_jid:usr_bare(), NodeIdx::exmpp_pubsub:nodeIdx()},
+         nodeidx :: exmpp_pubsub:nodeIdx(),
+         subids  :: [SubId::exmpp_pubsub:subId(),...]
+     }
+).
+
+
+
+
+
+-define(PROCNAME, ejabberd_mod_pubsub_dev).
+
+
+
+
+
+
+
+-record(state,
+{
+  host           :: xmpp_jid:raw_jid_component_bare(),
+  pubsub_host    :: xmpp_jid:raw_jid_component_bare(),
+  pubsub         :: #capabilities{},
+  pubsub_on_jid  :: #capabilities{}
+}).
+
+-type(state()
+  :: #state{
+         host           :: xmpp_jid:raw_jid_component_bare(),
+         pubsub_host    :: xmpp_jid:raw_jid_component_bare(),
+         pubsub         :: #capabilities{},
+         pubsub_on_jid  :: #capabilities{}
+     }
+).
+
+
+%%====================================================================
+%% API
+%%====================================================================
+%%--------------------------------------------------------------------
+%% Function: start_link() -> {ok,Pid} | ignore | {error,Error}
+%% Description: Starts the server
+%%--------------------------------------------------------------------
+
+%% @spec start_link(Host, Options) -> {'ok', pid()} | 'ignore' | {'error', atom()}
+%%     Host = string()
+%%     Options = {Option::atom(), Value::term()}
+-spec(start_link/2 ::
+(
+  Host    :: string(),
+  Options :: [Option::{Key::atom(), Value::term()}])
+    -> {'ok', pid()} | 'ignore' | {'error', _}
+).
+
+start_link(Host, Options) ->
+    Proc = gen_mod:get_module_proc(Host, ?PROCNAME),
+    gen_server:start_link({local, Proc}, ?MODULE, [Host, Options], []).
+
+%% @spec start(Host, Options) -> {'error',atom()} | {'ok','undefined' | pid()} | {'ok','undefined' | pid(),any()}
+%%     Host = string()
+%%     Options = {Option::atom(), Value::term()}
+-spec(start/2 ::
+(
+  Host    :: string(),
+  Options :: [Option::{Key::atom(), Value::term()}])
+    -> {'error',_} | {'ok','undefined' | pid()} | {'ok','undefined' | pid(),_}
+).
+
+start(Host, Options) ->
+    Proc = gen_mod:get_module_proc(Host, ?PROCNAME),
+    ChildSpec = {Proc,
+		 {?MODULE, start_link, [Host, Options]},
+		 transient, 1000, worker, [?MODULE]},
+    supervisor:start_child(ejabberd_sup, ChildSpec).
+
+%% @spec stop(Host) -> 'ok' | {'error','not_found' | 'running' | 'simple_one_for_one'}
+%%     Host = string()
+-spec(stop/1 ::
+(
+  Host :: string())
+    -> 'ok' | {'error','not_found' | 'running' | 'simple_one_for_one'}
+).
+
+stop(Host) ->
+    Proc = gen_mod:get_module_proc(Host, ?PROCNAME),
+    gen_server:call(Proc, stop),
+    supervisor:delete_child(ejabberd_sup, Proc).
+
+
+
+
+%%====================================================================
+%% gen_server callbacks
+%%====================================================================
+
+%%--------------------------------------------------------------------
+%% Function: init(Args) -> {ok, State} |
+%%                         {ok, State, Timeout} |
+%%                         ignore               |
+%%                         {stop, Reason}
+%% Description: Initiates the server
+%%--------------------------------------------------------------------
+-spec(init/1 ::
+(
+  Args :: [binary() | [{Option::atom(), Value::term()}]])
+    -> {'ok', State::state()}
+).
+
+init([Host, Options] = _Args) ->
+    ?DEBUG("pubsub init ~p ~p",[Host, Options]),
+    Pubsub_Host = gen_mod:expand_host_name(Host, Options, <<"pubsub">>),
+    IQDisc = gen_mod:get_opt('iqdisc', Options, 'one_queue'),
+
+   % mod_disco:register_feature(Server_HostB, ?NS_PUBSUB_s),
+   %%
+   %% Pubsub Hooks
+   %%   - Service disco hooks
+   %%     * disco_local_identity
+   %%     * disco_local_features
+   %%     * disco_local_items
+   %%     * disco_local_forms
+   %%   - Connectivity hooks
+   %%     * presence_probe_hook
+   %%     * sm_remove_connection_hook
+   %%   - Roster hooks
+   %%     * roster_in_subscription
+   %%     * roster_out_subscription
+   %%   - User managment hooks
+   %%     * remove_user
+   %%     * anonymous_purge_hook
+   %%
+   %% Pubsub On Jid hooks
+   %%   - Service disco hooks
+   %%     * disco_sm_identity
+   %%     * disco_sm_features
+   %%     * disco_sm_items
+   %%     * disco_sm_forms
+   %%   - Connectitivy
+   %%     * caps_update
+
+
+    Pubsub_Features = node_flat_dev:pubsub_features(),
+   % mod_disco:register_feature(Server_HostB, ?NS_PUBSUB_s),
+    pubsub_db:init('mnesia', 'dev'),
+    %% Register hooks according to available Pubsub Features
+    register_hooks(Host, Pubsub_Features, pubsub_hooks),
+    %%
+    ejabberd_router:register_route(Pubsub_Host),
+    {ok,
+     #state{
+         host        = Host,
+         pubsub_host = Pubsub_Host,
+         pubsub      = node_flat_dev:capabilities()
+     }
+    }.
+
+%%--------------------------------------------------------------------
+%% Function:
+%% handle_call(Request, From, State) -> {reply, Reply, State} |
+%%                                      {reply, Reply, State, Timeout} |
+%%                                      {noreply, State} |
+%%                                      {noreply, State, Timeout} |
+%%                                      {stop, Reason, Reply, State} |
+%%                                      {stop, Reason, State}
+%% Description: Handling call messages
+%%--------------------------------------------------------------------
+%% @private
+
+handle_call(stop, _From, State) ->
+    {stop, normal, ok, State}.
+
+%%--------------------------------------------------------------------
+%% Function: handle_cast(Msg, State) -> {noreply, State} |
+%%                                      {noreply, State, Timeout} |
+%%                                      {stop, Reason, State}
+%% Description: Handling cast messages
+%%--------------------------------------------------------------------
+%% @private
+handle_cast(_Msg, State) ->
+    {noreply, State}.
+
+%%--------------------------------------------------------------------
+%% Function: handle_info(Info, State) -> {noreply, State} |
+%%                                       {noreply, State, Timeout} |
+%%                                       {stop, Reason, State}
+%% Description: Handling all non call/cast messages
+%%--------------------------------------------------------------------
+%% @private
+
+handle_info({route, From, #jid{resource = undefined} = To, Stanza},
+  #state{host = Host, pubsub = Capabilities} = State) ->
+    do_route(Host, To, From, Stanza, Capabilities),
+    {noreply, State};
+%%
+handle_info(_Info, State) ->
+    {noreply, State}.
+
+%%--------------------------------------------------------------------
+%% Function: terminate(Reason, State) -> void()
+%% Description: This function is called by a gen_server when it is about to
+%% terminate. It should be the opposite of Module:init/1 and do any necessary
+%% cleaning up. When it returns, the gen_server terminates with Reason.
+%% The return value is ignored.
+%%--------------------------------------------------------------------
+%% @private
+%% @todo : -spec
+-spec(terminate/2 ::
+(
+  Reason :: _,
+  State  :: state())
+    -> 'ok'
+).
+
+terminate(_Reason, #state{host = Host, pubsub_host = Pubsub_Host}) ->
+    ejabberd_router:unregister_route(Pubsub_Host),
+    ok.
+
+%%--------------------------------------------------------------------
+%% Func: code_change(OldVsn, State, Extra) -> {ok, NewState}
+%% Description: Convert process state when code is changed
+%%--------------------------------------------------------------------
+%% @private
+code_change(_OldVsn, State, _Extra) ->
+    {ok, State}.
+
+
+%%
+-define(Is_Stanza_IQ(Stanza),
+(
+  Stanza#xmlel.name == <<"iq">>
+)).
+
+-define(Is_Stanza_Message(Stanza),
+(
+  Stanza#xmlel.name == <<"message">>
+)).
+
+-define(Is_Stanza_Presence(Stanza),
+(
+  Stanza#xmlel.name == <<"presence">>
+)).
+
+-define(Is_IQ_Ignore(IQ),
+(
+  IQ#iq.type == 'result'
+    orelse
+  IQ#iq.type == 'error'
+)).
+
+-define(Is_IQ_Pubsub(IQ),
+(
+  (IQ#iq.type == 'set'
+       orelse
+   IQ#iq.type == 'get')
+           andalso
+  (IQ#iq.xmlns == ?NS_PUBSUB
+       orelse
+   IQ#iq.xmlns == ?NS_PUBSUB_OWNER)
+          andalso
+  IQ#iq.sub_el#xmlel.name == <<"pubsub">>
+)).
+
+-define(Is_IQ_Get_Disco_Info(IQ),
+(
+  IQ#iq.type                   == 'get'
+    andalso
+  IQ#iq.xmlns                  == ?NS_DISCO_INFO
+    andalso
+  IQ#iq.sub_el#xmlel.name      == <<"query">>
+%    andalso
+%  IQ#iq.payload#xmlel.children == []
+)).
+
+-define(Is_IQ_Get_Disco_Items(IQ),
+(
+  IQ#iq.type                   == 'get'
+    andalso
+  IQ#iq.xmlns                  == ?NS_DISCO_ITEMS
+    andalso
+  IQ#iq.sub_el#xmlel.name      == <<"query">>
+%    andalso
+%  IQ#iq.payload#xmlel.children == []
+)).
+
+%%
+do_route(Host,
+  #jid{lserver = Pubsub_Host} = Pubsub_Component,
+  #jid{luser = U, lserver = S, lresource = R} = Entity, Stanza_IQ,
+  #capabilities{privacy = Privacy, plugin = Plugin} = Capabilities)
+  when ?Is_Stanza_IQ(Stanza_IQ) ->
+    case IQ = jlib:iq_query_or_response_info(Stanza_IQ) of
+        IQ when ?Is_IQ_Ignore(IQ) ->
+            ok;
+        IQ when ?Is_IQ_Get_Disco_Info(IQ) ->
+            case
+                pubsub_disco:iq_disco_info('dev', Host, Pubsub_Host,
+                    Privacy, {U,S,undefined},
+                    case S of
+                        Host -> 'local';
+                        _    -> 'remote'
+                    end,
+                    Plugin,
+                    case xml:get_tag_attr_s(<<"node">>, IQ#iq.sub_el) of
+                        <<>>   -> undefined;
+                        NodeId -> NodeId
+                    end,
+                    xml:remove_cdata(IQ#iq.sub_el#xmlel.children))
+            of
+                {result, Xmlel_Query} ->
+                    ejabberd_router:route(Pubsub_Component, Entity,
+                        jlib:iq_to_xml(IQ#iq{
+                            type   = result,
+                            sub_el = [Xmlel_Query]
+                        }));
+                {error, Error} ->
+                    ejabberd_router:route(Pubsub_Component, Entity,
+                        jlib:make_error_reply(Stanza_IQ, Error))
+            end;
+        IQ when ?Is_IQ_Get_Disco_Items(IQ) ->
+            case
+                pubsub_disco:iq_disco_items('dev', Host, Pubsub_Host,
+                    Privacy, {U,S,undefined},
+                    case S of
+                        Host -> 'local';
+                        _    -> 'remote'
+                    end,
+                    Plugin,
+                    case xml:get_tag_attr_s(<<"node">>, IQ#iq.sub_el) of
+                        <<>>   -> undefined;
+                        NodeId -> NodeId
+                    end,
+                    xml:remove_cdata(IQ#iq.sub_el#xmlel.children))
+            of
+                {result, Xmlel_Query} ->
+                    ejabberd_router:route(Pubsub_Component, Entity,
+                        jlib:iq_to_xml(IQ#iq{
+                            type   = result,
+                            sub_el = [Xmlel_Query]
+                        }));
+                {error, Error} ->
+                    ejabberd_router:route(Pubsub_Component, Entity,
+                        jlib:make_error_reply(Stanza_IQ, Error))
+            end;
+        IQ when ?Is_IQ_Pubsub(IQ) ->
+            case
+                iq_pubsub(Host, Pubsub_Host, {U,S,R}, IQ#iq.type,
+                    _Rsm = lists:member(?NS_RSM, Plugin:features()),
+                    xml:remove_cdata(IQ#iq.sub_el#xmlel.children),
+                    IQ#iq.lang, Capabilities)
+            of
+                {result, []} ->
+                    ejabberd_router:route(Pubsub_Component, Entity,
+                        jlib:iq_to_xml(IQ#iq{
+                            type   = result,
+                            sub_el = []
+                        }));
+                {result, Xmlels} ->
+                    ejabberd_router:route(Pubsub_Component, Entity,
+                        jlib:iq_to_xml(IQ#iq{
+                            type   = result,
+                            sub_el = Xmlels
+                        }));
+                {error, Error} ->
+                    ejabberd_router:route(Pubsub_Component, Entity,
+                        jlib:make_error_reply(Stanza_IQ, Error))
+            end
+    end;
+do_route(Host,
+  #jid{lserver = Pubsub_Host} = Pubsub_Component,
+  #jid{luser = U, lserver = S, lresource = R} = Entity, Stanza_Message,
+  Capabilities)
+  when ?Is_Stanza_Message(Stanza_Message) ->
+    ok;
+do_route(Host,
+  #jid{lserver = Pubsub_Host} = Pubsub_Component,
+  #jid{luser = U, lserver = S, lresource = R} = Entity, Stanza_Presence,
+  Capabilities)
+  when ?Is_Stanza_Presence(Stanza_Presence) ->
+    ok.
+
+
+iq_pubsub(Host, Pubsub_Host, Entity, IQ_Type, Rsm, Xmlels, _Lang,
+  #capabilities{api = #api{parser = Parser, core = API_Core}} = Capabilities) ->
+    case Parser:parse(IQ_Type, Xmlels, Rsm, API_Core) of
+        {result, Module, Function, Parameters} ->
+            Module:Function(Host, Pubsub_Host, Entity, Parameters, Capabilities);
+        Error ->
+            Error
+    end.
+
+
+
+register_hooks(Host, Pubsub_Features, Module) ->
+    register_hooks('roster', Host, Pubsub_Features, Module),
+    register_hooks('presence', Host, Pubsub_Features, Module).
+
+    %ejabberd_hooks:add(roster_in_subscription, Host, pubsub_hooks, roster_in_subscription, 50),
+    %ejabberd_hooks:add(roster_out_subscription, Host, ?MODULE, roster_out_subscription, 50),
+    %ejabberd_hooks:add(roster_get, Host, ?MODULE, roster_get, 50),
+    %ejabberd_hooks:add(roster_get_jid_info, Host, ?MODULE, roster_get_jid_info, 50),
+    %ejabberd_hooks:add(roster_get_subscription_lists, Host, ?MODULE, roster_get_subscription_lists, 50),
+    %%ejabberd_hooks:add(roster_process_item, Host, pubsub_hooks, roster_process_item, 50).
+
+
+register_hooks('roster', Host, Pubsub_Features, Module) ->
+    case lists:member("access-roster", Pubsub_Features) of
+        true ->
+            ejabberd_hooks:add(roster_process_item, Host, Module,
+                roster_process_item, 50),
+            ok;
+        false ->
+            ok
+    end;
+%%
+register_hooks('presence', Host, Pubsub_Features, Module) ->
+    case
+        lists:member(<<"access-presence">>, Pubsub_Features)
+            orelse
+        lists:member(<<"last-published">>, Pubsub_Features)
+            orelse
+        lists:member(<<"leased-subscription">>, Pubsub_Features)
+            orelse
+        lists:member(<<"presence-notifications">>, Pubsub_Features)
+    of
+        true ->
+            ejabberd_hooks:add(presence_probe_hook, Host, Module,
+                presence_online, 80),
+            ejabberd_hooks:add(sm_remove_connection_hook, Host, Module,
+                presence_offline, 80),
+            ok;
+        false ->
+            ok
+    end.
+
+
+roster_get(Acc, {User, Server}) ->
+    ?INFO_MSG("ROSTER_GET Acc ~p ~nUser ~p ~nServer ~p ~n",
+        [Acc, User, Server]).
+
+roster_get_jid_info(Acc, User, Server, JID) ->
+    ?INFO_MSG("ROSTER_GET_JID_INFO Acc ~p ~nUser ~p ~nServer ~p ~nJID ~p ~n",
+        [Acc, User, Server, JID]).
+
+roster_get_subscription_lists(Acc, User, Server) ->
+    ?INFO_MSG("ROSTER_GET_SUBSCRIPTION_LISTS Acc ~p ~nUser ~p ~nServer ~p ~n",
+        [Acc, User, Server]).
+
+roster_in_subscription(User, Server, JID, SubscriptionType, Reason, A) ->
+    ?INFO_MSG("ROSTER_IN_SUBSCRITION User  ~p ~n Server ~p ~n JID ~p ~n SubscriptionType ~p ~n, Reason ~p ~nA ~p ~n",
+        [User, Server, JID, SubscriptionType, Reason, A]).
+
+roster_out_subscription(User, Server, JID, SubscriptionType) ->
+    ?INFO_MSG("ROSTER_OUT_SUBSCRITION User  ~p ~n Server ~p ~n JID ~p ~n SubscriptionType ~p ~n",
+        [User, Server, JID, SubscriptionType]).
+
+roster_process_item(RosterItem, Server) ->
+        ?INFO_MSG("ROSTER_PROCESS_ITEM RosterItem ~p ~nServer ~p ~n",
+        [RosterItem, Server]),
+        RosterItem.
+
diff --git a/src/mod_pubsub_ng/node_flat_dev.erl b/src/mod_pubsub_ng/node_flat_dev.erl
new file mode 100644
index 000000000..9de5e5a1f
--- /dev/null
+++ b/src/mod_pubsub_ng/node_flat_dev.erl
@@ -0,0 +1,310 @@
+%%% ====================================================================
+%%% ``The contents of this file are subject to the Erlang Public License,
+%%% Version 1.1, (the "License"); you may not use this file except in
+%%% compliance with the License. You should have received a copy of the
+%%% Erlang Public License along with this software. If not, it can be
+%%% retrieved via the world wide web at http://www.erlang.org/.
+%%% 
+%%% Software distributed under the License is distributed on an "AS IS"
+%%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%%% the License for the specific language governing rights and limitations
+%%% under the License.
+%%% 
+%%% The Initial Developer of the Original Code is ProcessOne.
+%%% Portions created by ProcessOne are Copyright 2006-2011, ProcessOne
+%%% All Rights Reserved.''
+%%% This software is copyright 2006-2011, ProcessOne.
+%%%
+%%% @copyright 2006-2011 ProcessOne
+%%% @author Karim Gemayel <karim.gemayel@process-one.net>
+%%%   [http://www.process-one.net/]
+%%% @version {@vsn}, {@date} {@time}
+%%% @end
+%%% ====================================================================
+
+%%% @headerfile "pubsub_dev.hrl"
+
+-module(node_flat_dev).
+-author('karim.gemayel@process-one.net').
+
+-include("pubsub_dev.hrl").
+-include("pubsub_api.hrl").
+
+-compile(export_all).
+
+
+
+%%
+-spec(capabilities/0 :: () -> #capabilities{}).
+
+capabilities() ->
+    #capabilities{plugin = ?MODULE}.
+
+
+%%
+-spec(pubsub_features/0 :: () -> Pubsub_Features::exmpp_pubsub:pubsub_features()).
+
+pubsub_features() ->
+    [<<"access-authorize">>,
+     <<"access-open">>,
+     <<"access-presence">>,
+     <<"access-roster">>,
+     <<"access-whitelist">>,
+     <<"auto-create">>,
+     <<"auto-subscribe">>,
+    %<<"collections">>,
+     <<"config-node">>,
+     <<"create-and-configure">>,
+     <<"create-nodes">>,
+     <<"delete-items">>,
+     <<"delete-nodes">>,
+    %<<"filtered-notifications">>,
+     <<"get-pending">>,
+     <<"instant-nodes">>,
+     <<"item-ids">>,
+     <<"last-published">>,
+     <<"leased-subscription">>,
+     <<"manage-subscriptions">>,
+     <<"member-affiliation">>,
+     <<"meta-data">>,
+     <<"modify-affiliations">>,
+    %<<"multi-collections">>,
+     <<"multi-subscribe">>,
+     <<"outcast-affiliation">>,
+     <<"persistent-items">>,
+     <<"presence-notifications">>,
+    %"presence-subscribe">>,
+     <<"publish">>,
+     <<"publish-only-affiliation">>,
+     <<"publish-options">>,
+     <<"publisher-affiliation">>,
+     <<"purge-nodes">>,
+     <<"retract-items">>,
+     <<"retrieve-affiliations">>,
+     <<"retrieve-default">>,
+     <<"retrieve-default-sub">>,
+     <<"retrieve-items">>,
+     <<"retrieve-subscriptions">>,
+     <<"subscribe">>,
+     <<"subscription-notifications">>,
+     <<"subscription-options">>].
+
+%%
+-spec(pubsub_features/1 ::
+(
+  Entity_Type :: 'local' | 'remote')
+    -> Pubsub_Features::exmpp_pubsub:pubsub_features()
+).
+
+pubsub_features('local') ->
+    [<<"access-authorize">>,
+     <<"access-open">>,
+     <<"access-presence">>,
+     <<"access-roster">>,
+     <<"access-whitelist">>,
+     <<"auto-create">>,
+     <<"auto-subscribe">>,
+    %<<"collections">>,
+     <<"config-node">>,
+     <<"create-and-configure">>,
+     <<"create-nodes">>,
+     <<"delete-items">>,
+     <<"delete-nodes">>,
+    %<<"filtered-notifications">>,
+     <<"get-pending">>,
+     <<"instant-nodes">>,
+     <<"item-ids">>,
+     <<"last-published">>,
+     <<"leased-subscription">>,
+     <<"manage-subscriptions">>,
+     <<"member-affiliation">>,
+     <<"meta-data">>,
+     <<"modify-affiliations">>,
+    %<<"multi-collections">>,
+     <<"multi-subscribe">>,
+     <<"outcast-affiliation">>,
+     <<"persistent-items">>,
+     <<"presence-notifications">>,
+    %<<"presence-subscribe">>,
+     <<"publish">>,
+     <<"publish-only-affiliation">>,
+     <<"publish-options">>,
+     <<"publisher-affiliation">>,
+     <<"purge-nodes">>,
+     <<"retract-items">>,
+     <<"retrieve-affiliations">>,
+     <<"retrieve-default">>,
+     <<"retrieve-default-sub">>,
+     <<"retrieve-items">>,
+     <<"retrieve-subscriptions">>,
+     <<"subscribe">>,
+     <<"subscription-notifications">>,
+     <<"subscription-options">>];
+%%
+pubsub_features('remote') ->
+    [<<"access-authorize">>,
+     <<"access-open">>,
+     <<"access-presence">>,
+     <<"access-roster">>,
+     <<"access-whitelist">>,
+     <<"auto-create">>,
+     <<"auto-subscribe">>,
+    %<<"collections">>,
+     <<"config-node">>,
+     <<"create-and-configure">>,
+     <<"create-nodes">>,
+     <<"delete-items">>,
+     <<"delete-nodes">>,
+    %<<"filtered-notifications">>,
+     <<"get-pending">>,
+     <<"instant-nodes">>,
+     <<"item-ids">>,
+     <<"last-published">>,
+    %<<"leased-subscription">>,
+     <<"manage-subscriptions">>,
+     <<"member-affiliation">>,
+     <<"meta-data">>,
+     <<"modify-affiliations">>,
+    %<<"multi-collections">>,
+     <<"multi-subscribe">>,
+     <<"outcast-affiliation">>,
+     <<"persistent-items">>,
+     <<"publish">>,
+     <<"publish-only-affiliation">>,
+     <<"publish-options">>,
+     <<"publisher-affiliation">>,
+     <<"purge-nodes">>,
+     <<"retract-items">>,
+     <<"retrieve-affiliations">>,
+     <<"retrieve-default">>,
+     <<"retrieve-default-sub">>,
+     <<"retrieve-items">>,
+     <<"retrieve-subscriptions">>,
+     <<"subscribe">>,
+     <<"subscription-notifications">>,
+     <<"subscription-options">>].
+
+%%
+%%
+-spec(node_options/1 ::
+(
+  Node_Type :: 'leaf' | 'collection')
+    -> Node_Options :: pubsub_options:options_node_leaf()
+                     | pubsub_options:options_node_collection()
+).
+
+node_options('leaf') ->
+    [{'access_model', open},
+     {'contact', []},
+    %{'collection', []},
+     {'deliver_notifications', true},
+     {'deliver_payloads', true},
+     {'description', undefined},
+     {'item_expire', undefined},
+     {'itemreply', publisher},
+     {'language', <<"en">>},
+     {'max_items', 2},
+     {'max_payload_size', undefined},
+     {'node_type', leaf},
+     {'notification_type', normal},
+     {'notify_config', true},
+     {'notify_delete', true},
+     {'notify_retract', true},
+     {'notify_sub', true},
+     {'persist_items', true},
+     {'presence_based_delivery', true},
+     {'publish_model', open},
+     {'purge_offline', false},
+     {'roster_groups_allowed', []},
+     {'send_last_published_item', on_sub_and_presence},
+     {'subscribe', true},
+     {'tempsub', false},
+     {'title', undefined},
+     {'type', undefined}];
+%%
+node_options('collection') ->
+    [].
+
+item_options() ->
+    [{'access_model', open},
+     {'deliver_notifications', true},
+     {'deliver_payloads', true},
+     {'item_expire', undefined},
+     {'itemreply', publisher},
+%    {'max_payload_size', undefined},
+     {'notification_type', normal},
+     {'notify_config', true},
+     {'notify_retract', true},
+     {'persist_items', true},
+     {'presence_based_delivery', true},
+%    {'publish_model', open},
+     {'purge_offline', false},
+     {'roster_groups_allowed', []},
+     {'send_last_published_item', on_sub_and_presence},
+     {'type', undefined}].
+
+%%
+-spec(subscription_options/2 ::
+(
+  Entity_Type :: 'local' | 'remote',
+  Node_Type   :: 'leaf' | 'collection')
+    -> Subscription_Options :: [] | pubsub_options:options_subscription()
+).
+
+subscription_options('local', 'leaf') ->
+    [];
+subscription_options('remote', 'leaf') ->
+    [];
+subscription_options('local', 'collection') ->
+    [];
+subscription_options('remote', 'collection') ->
+    [].
+
+%%
+-spec(default_subscription_options/2 ::
+(
+  Entity_Type :: 'local' | 'remote',
+  Node_Type   :: 'leaf')%| 'collection')
+    -> Subscription_Options :: pubsub_options:options_subscription_leaf()
+).
+
+default_subscription_options('local', 'leaf') ->
+    [{'deliver', true},
+     {'expire', undefined},
+    %{'include_body', undefined},
+     {'show-values', ['away', 'chat', 'dnd', 'online', 'xa']}];
+%%
+default_subscription_options('remote', 'leaf') ->
+    [{'deliver', true}
+    %{'include_body', undefined}
+    ].
+%%
+%%default_subscription_options('local', 'collection') ->
+%%    [{'deliver', true},
+%%    %{'expire', undefined},
+%%    %{'include_body', undefined},
+%%     {'show-values', ['away', 'chat', 'dnd', 'online', 'xa']},
+%%     {'subscription_type', 'all'},
+%%     {'subscription_depth', 1}];
+%%
+%%default_subscription_options('remote', 'collection') ->
+%%    [{'deliver', true},
+%%    %{'include_body', undefined},
+%%     {'show-values', ['away', 'chat', 'dnd', 'online', 'xa']},
+%%     {'subscription_type', 'all'},
+%%     {'subscription_depth', 1}].
+
+%%
+-spec(features/0 :: () -> Features::exmpp_pubsub:features()).
+
+features() ->
+    [%?NS_ADDRESS,
+     ?NS_DISCO_INFO,
+     ?NS_DISCO_ITEMS,
+     %?NS_RSM,
+     ?NS_VCARD].
+
+%%
+identity() ->
+    [{<<"pubsub">>, <<"Publish-Subscribe">>, <<"service">>},
+     {<<"pubsub">>, <<"ejabberd/mod_pubsub/flat">>, <<"service">>}].
diff --git a/src/mod_pubsub_ng/pubsub_api.hrl b/src/mod_pubsub_ng/pubsub_api.hrl
new file mode 100644
index 000000000..a948d3575
--- /dev/null
+++ b/src/mod_pubsub_ng/pubsub_api.hrl
@@ -0,0 +1,101 @@
+%% API function definition
+
+-record(api_core,
+{
+  create_node                        = 'pubsub_core' :: module(),
+  delete_node                        = 'pubsub_core' :: module(),
+  purge_node                         = 'pubsub_core' :: module(),
+  get_configure_node                 = 'pubsub_core' :: module(),
+  get_configure_node_default         = 'pubsub_core' :: module(),
+  %%
+  publish_item                       = 'pubsub_core' :: module(),
+  retract_item                       = 'pubsub_core' :: module(),
+  %%
+  subscribe_node                     = 'pubsub_core' :: module(),
+  unsubscribe_node                   = 'pubsub_core' :: module(),
+  set_configure_subscription         = 'pubsub_core' :: module(),
+  get_configure_subscription         = 'pubsub_core' :: module(),
+  get_configure_subscription_default = 'pubsub_core' :: module(),
+  get_items                          = 'pubsub_core' :: module(),
+  %%
+  get_entity_affiliations            = 'pubsub_core' :: module(),
+  get_entity_subscriptions           = 'pubsub_core' :: module(),
+  %%
+  get_node_affiliations              = 'pubsub_core' :: module(),
+  get_node_subscriptions             = 'pubsub_core' :: module()
+}).
+
+-record(api_db,
+{
+  create_node                        = 'pubsub_db' :: module(),
+  delete_node                        = 'pubsub_db' :: module(),
+  purge_node                         = 'pubsub_db' :: module(),
+  get_configure_node                 = 'pubsub_db' :: module(),
+ %get_configure_node_default         = 'pubsub_db' :: module(),
+  %%
+  publish_item                       = 'pubsub_db' :: module(),
+  retract_item                       = 'pubsub_db' :: module(),
+  %%
+  subscribe_node                     = 'pubsub_db' :: module(),
+  unsubscribe_node                   = 'pubsub_db' :: module(),
+  set_configure_subscription         = 'pubsub_db' :: module(),
+  get_configure_subscription         = 'pubsub_db' :: module(),
+  get_configure_subscription_default = 'pubsub_db' :: module(),
+  get_items                          = 'pubsub_db' :: module(),
+  %%
+  get_entity_affiliations            = 'pubsub_db' :: module(),
+  get_entity_subscriptions           = 'pubsub_db' :: module(),
+  %%
+  get_node_affiliations              = 'pubsub_db' :: module(),
+  get_node_subscriptions             = 'pubsub_db' :: module()
+}).
+
+-record(api_broadcast,
+{
+  broadcast_publish      = 'pubsub_broadcast' :: module(),
+  broadcast_publish_last = 'pubsub_broadcast' :: module(),
+  notify_create          = 'pubsub_broadcast' :: module(),
+  notify_delete          = 'pubsub_broadcast' :: module(),
+  notify_publish         = 'pubsub_broadcast' :: module(),
+  notify_purge           = 'pubsub_broadcast' :: module(),
+  notify_retract         = 'pubsub_broadcast' :: module(),
+  notify_subscription    = 'pubsub_broadcast' :: module(),
+  notify_subscriptions   = 'pubsub_broadcast' :: module()
+}).
+
+-record(api,
+{
+  core      = #api_core{}      :: #api_core{},
+  db        = #api_db{}        :: #api_db{},
+  broadcast = #api_broadcast{} :: #api_broadcast{},
+  parser    = 'pubsub_parser'  :: module(),
+  options   = 'pubsub_options' :: module()
+}).
+
+-record(capabilities,
+{
+  plugin           :: exmpp_pubsub:plugin(),
+  privacy = false  :: boolean(),
+  api     = #api{} :: #api{}
+}).
+
+-record(api2,
+{
+  func,
+  core :: 'core',
+  db   :: 'db',
+  bkd  :: 'mnesia',
+  rtr  :: 'router'
+}).
+
+-record(mod_pubsub,
+{
+  server,
+  component,
+  plugin,
+  entity,
+  parameters,
+  features,
+  parser,
+  options
+}).
diff --git a/src/mod_pubsub_ng/pubsub_broadcast.erl b/src/mod_pubsub_ng/pubsub_broadcast.erl
new file mode 100644
index 000000000..33dce8a49
--- /dev/null
+++ b/src/mod_pubsub_ng/pubsub_broadcast.erl
@@ -0,0 +1,1240 @@
+%%% ====================================================================
+%%% ``The contents of this file are subject to the Erlang Public License,
+%%% Version 1.1, (the "License"); you may not use this file except in
+%%% compliance with the License. You should have received a copy of the
+%%% Erlang Public License along with this software. If not, it can be
+%%% retrieved via the world wide web at http://www.erlang.org/.
+%%% 
+%%% Software distributed under the License is distributed on an "AS IS"
+%%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%%% the License for the specific language governing rights and limitations
+%%% under the License.
+%%% 
+%%% The Initial Developer of the Original Code is ProcessOne.
+%%% Portions created by ProcessOne are Copyright 2006-2011, ProcessOne
+%%% All Rights Reserved.''
+%%% This software is copyright 2006-2011, ProcessOne.
+%%%
+%%% @copyright 2006-2011 ProcessOne
+%%% @author Karim Gemayel <karim.gemayel@process-one.net>
+%%%   [http://www.process-one.net/]
+%%% @version {@vsn}, {@date} {@time}
+%%% @end
+%%% ====================================================================
+
+%%% @headerfile "pubsub_dev.hrl"
+
+-module(pubsub_broadcast).
+-author('karim.gemayel@process-one.net').
+
+-compile(export_all).
+
+-include("pubsub_dev.hrl").
+-include("pubsub_api.hrl").
+
+
+-import(pubsub_tools,
+[
+  get_option/2,
+  get_option/3,
+  get_value/2,
+  get_value/3,
+  set_value/3,
+  %%
+  check_access_model/3,
+  check_access_model/7,
+  check_publish_model/3,
+  is_contact_subscribed_to_node_owners/3,
+  is_contact_in_allowed_roster_groups/2,
+  has_subscriptions/1,
+  get_resources/2,
+  get_resources_show/2,
+  rosters_groups_allowed_cache/2
+]).
+
+
+-spec(notify_subscriptions/5 ::
+(
+  Host                   :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host            :: exmpp_pubsub:host(),
+  NodeId                 :: exmpp_pubsub:nodeId(),
+  Notification_Type      :: pubsub_options:notification_type(),
+  Entities_Subscriptions :: [Entity_Subscriptions :: {
+                                 Entity :: xmpp_jid:usr_entity(),
+                                 Subscriptions :: _%sub:subscriptions()
+                             }])
+    -> 'ok'
+).
+
+notify_subscriptions(_Host, Pubsub_Host, NodeId, Notification_Type,
+  Entities_Subscriptions) ->
+    Pubsub_Component_Jid = jlib:make_jid(<<>>, Pubsub_Host, <<>>),
+    lists:foreach(fun
+        (_Entity = {{U,S,_R}, Subscriptions}) ->
+            lists:foreach(fun
+                ({Subscription_State, SubId, Resource, _Subscription_Options}) ->
+                    Recipient_Jid = jlib:make_jid(U,S,Resource),
+                    ejabberd_router:route(_From = Pubsub_Component_Jid,
+                        _To = Recipient_Jid,
+                        _Stanza_Message = exmpp_pubsub:xmlel_message(
+                            Notification_Type,
+                            [exmpp_pubsub:xmlel_event([
+                                 exmpp_pubsub:xmlel_subscription('pubsub#event',
+                                     NodeId,
+                                     _Jid = pubsub_tools:jid_to_string(Recipient_Jid),
+                                     SubId,
+                                     Subscription_State
+                                 )
+                             ])]
+                        )
+                    )
+            
+            end, Subscriptions)
+    end, Entities_Subscriptions).
+
+%%
+-spec(notify_subscription/6 ::
+(
+  Host                 :: xmpp_jid:raw_jid_component_bare(),
+  NodeId               :: exmpp_pubsub:nodeId(),
+  Pubsub_Component_Jid :: xmpp_jid:component_bare(),
+  Recipient            :: xmpp_jid:entity_bare() | [xmpp_jid:entity_bare(),...],
+  Notification_Type    :: pubsub_options:notification_type(),
+  Subscription         :: {
+    Subscriber         :: xmpp_jid:raw_jid_entity(),
+    Subscription_State :: exmpp_pubsub:subscription_state(),
+    SubId              :: exmpp_pubsub:subId()
+  })
+    -> 'ok'
+).
+
+notify_subscription(_Host, NodeId, Pubsub_Component_Jid, Recipients,
+  Notification_Type, {Subscriber, Subscription_State, SubId})
+  when is_list(Recipients) ->
+    Stanza_Message = exmpp_pubsub:xmlel_message(Notification_Type,
+      [exmpp_pubsub:xmlel_event([
+           exmpp_pubsub:xmlel_subscription('pubsub#event',
+               NodeId, Subscriber, SubId, Subscription_State)
+            ])
+        ]),
+    lists:foreach(fun
+        (Recipient) ->
+            ejabberd_router:route(_From = Pubsub_Component_Jid,
+                _To = pubsub_tools:make_jid(Recipient), Stanza_Message)
+    end, Recipients);
+%%
+notify_subscription(_Host, NodeId, Pubsub_Component_Jid, Recipient,
+  Notification_Type, {Subscriber, Subscription_State, SubId}) ->
+  Stanza_Message = exmpp_pubsub:xmlel_message(Notification_Type,
+      [exmpp_pubsub:xmlel_event([
+           exmpp_pubsub:xmlel_subscription('pubsub#event',
+               NodeId, Subscriber, SubId, Subscription_State)
+            ])
+        ]),
+  ejabberd_router:route(_From = Pubsub_Component_Jid,
+    _To = Recipient, Stanza_Message).
+
+%%
+-spec(notify_delete/6 ::
+(
+  Host              :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host       :: exmpp_pubsub:host(),
+  NodeId            :: exmpp_pubsub:nodeId(),
+  Notification_Type :: pubsub_options:notification_type(),
+  RedirectURI       :: undefined | binary(),
+  Recipients        :: [Recipient::xmpp_jid:usr_bare(),...])
+    -> 'ok'
+).
+
+notify_delete(_Host, Pubsub_Host, NodeId, Notification_Type, RedirectURI,
+  Recipients) ->
+    Pubsub_Component_Jid = jlib:make_jid(<<>>, Pubsub_Host, <<>>),
+    Stanza_Message = exmpp_pubsub:xmlel_message(Notification_Type,
+        [exmpp_pubsub:xmlel_event([
+             exmpp_pubsub:xmlel_delete(NodeId, RedirectURI)])]
+    ),
+    lists:foreach(fun
+        (Recipient) ->
+            ejabberd_router:route(_To = Pubsub_Component_Jid,
+                _From = pubsub_tools:make_jid(Recipient),
+                Stanza_Message
+            )
+    end, Recipients).
+
+%%
+-spec(notify_purge/5 ::
+(
+  Host              :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host       :: exmpp_pubsub:host(),
+  NodeId            :: exmpp_pubsub:nodeId(),
+  Notification_Type :: pubsub_options:notification_type(),
+  Recipients        :: [Recipient::xmpp_jid:usr_bare(),...])
+    -> 'ok'
+).
+
+notify_purge(_Host, Pubsub_Host, NodeId, Notification_Type, Recipients) ->
+    Pubsub_Component_Jid = jlib:make_jid(<<>>, Pubsub_Host, <<>>),
+    Stanza_Message = exmpp_pubsub:xmlel_message(Notification_Type,
+        [exmpp_pubsub:xmlel_event([
+             exmpp_pubsub:xmlel_purge(NodeId)])]),
+    lists:foreach(fun
+        (Recipient) ->
+            ejabberd_router:route(_To = Pubsub_Component_Jid,
+                _From = pubsub_tools:make_jid(Recipient),
+                Stanza_Message
+            )
+    end, Recipients).
+
+%%
+-spec(notify_publish/8 ::
+(
+  From              :: xmpp_jid:component_bare(),
+  To                :: xmpp_jid:entity(),
+  Notification_Type :: 'headline' | 'normal',
+  NodeId            :: exmpp_pubsub:nodeId(),
+  ItemId            :: exmpp_pubsub:itemId(),
+  Publisher         :: undefined | xmpp_jid:raw_jid_entity(),
+  Payload           :: exmpp_pubsub:payload(),
+  SubIds            :: [SubId::exmpp_pubsub:subId(),...])
+    -> 'ok'
+).
+
+notify_publish(From, To, Notification_Type, NodeId, ItemId, Publisher, Payload,
+  SubIds) ->
+    ejabberd_router:route(From, To,
+        _Stanza_Message = exmpp_pubsub:xmlel_message(Notification_Type,
+            case SubIds of
+                [_SubId] ->
+                    [exmpp_pubsub:xmlel_event([
+                         exmpp_pubsub:xmlel_items('pubsub#event', NodeId,
+                             [exmpp_pubsub:xmlel_item('pubsub#event', ItemId,
+                                  Publisher, Payload)
+                             ])
+                         ])
+                    ];
+                _SubIds ->
+                    [exmpp_pubsub:xmlel_event([
+                         exmpp_pubsub:xmlel_items('pubsub#event', NodeId,
+                             [exmpp_pubsub:xmlel_item('pubsub#event', ItemId,
+                                  Publisher, Payload)
+                             ])
+                         ]),
+                     exmpp_pubsub:xmlel_headers(
+                        [exmpp_pubsub:xmlel_header(SubId) || SubId <- SubIds])
+                    ]
+            end)
+        ).
+
+
+-define(Xmlel(NS, Name, Attrs, Children),
+(
+    #xmlel{
+        name     = Name,
+        attrs    = [{<<"xmlns">>, NS} | Attrs],
+        children = Children
+    }
+)).
+
+-define(CData(Data),
+(
+    {xmlcdata, Data}
+)).
+
+-define(Stanza_Message(Type, Id, Children),
+(
+    ?Xmlel(?NS_JABBER_CLIENT, <<"message">>, [{<<"type">>, Type}, {<<"id">>, Id}],
+        Children)
+)).
+
+%%
+-spec(stanza_notify_publish/5 ::
+(
+  Notification_Type :: pubsub_options:notification_type(),
+  NodeId            :: exmpp_pubsub:nodeId(),
+  ItemId            :: exmpp_pubsub:itemId(),
+  Publisher         :: undefined | xmpp_jid:usr_entity() | xmpp_jid:raw_jid_entity(),
+  Payload           :: exmpp_pubsub:payload())
+    -> Stanza_Notify_Publish::xmlel()
+).
+
+stanza_notify_publish(Notification_Type, NodeId, ItemId, Publisher, Payload)
+  when is_tuple(Publisher) ->
+    stanza_notify_publish(Notification_Type, NodeId, ItemId,
+        pubsub_tools:jid_to_string(Publisher), Payload);
+
+stanza_notify_publish(Notification_Type, NodeId, ItemId, Publisher, Payload) ->
+    ?Stanza_Message(list_to_binary(atom_to_list(Notification_Type)), exmpp_pubsub:id(),[
+        ?Xmlel(?NS_PUBSUB_EVENT, <<"event">>, [], [
+            ?Xmlel(?NS_PUBSUB_EVENT, <<"items">>, [{<<"node">>, NodeId}], [
+                ?Xmlel(?NS_PUBSUB_EVENT, <<"item">>,
+                    case Publisher of
+                        undefined ->
+                            [{<<"id">>, ItemId}];
+                        _ ->
+                            [{<<"id">>, ItemId}, {<<"publisher">>, Publisher}]
+                    end,
+                    case Payload of
+                        [] -> [];
+                        _  -> [Payload]
+                    end)
+                ])
+            ])
+        ]).
+
+
+%%
+-spec(stanza_notify_retract/3 ::
+(
+  Notification_Type :: pubsub_options:notification_type(),
+  NodeId            :: exmpp_pubsub:nodeId(),
+  ItemId            :: exmpp_pubsub:itemId())
+    -> Stanza_Notify_Retract::xmlel()
+).
+
+stanza_notify_retract(Notification_Type, NodeId, ItemId) ->
+    ?Stanza_Message(list_to_binary(atom_to_list(Notification_Type)), exmpp_pubsub:id(),[
+        ?Xmlel(?NS_PUBSUB_EVENT, <<"event">>, [], [
+            ?Xmlel(?NS_PUBSUB_EVENT, <<"items">>, [{<<"node">>, NodeId}], [
+                ?Xmlel(?NS_PUBSUB_EVENT, <<"retract">>, [{<<"id">>, ItemId}], [])
+            ])
+        ])
+    ]).
+
+
+%%
+-spec(notify_retract/6 ::
+(
+  From              :: xmpp_jid:component_bare(),
+  To                :: xmpp_jid:entity(),
+  Notification_Type :: 'headline' | 'normal',
+  NodeId            :: exmpp_pubsub:nodeId(),
+  ItemId            :: exmpp_pubsub:itemId(),
+  SubIds            :: [SubId::exmpp_pubsub:subId(),...])
+    -> none
+).
+
+notify_retract(From, To, Notification_Type, NodeId, ItemId, SubIds) ->
+    ejabberd_router:route(From, To,
+        _Stanza_Message = exmpp_pubsub:xmlel_message(Notification_Type,
+            case SubIds of
+                [_SubId] ->
+                    [exmpp_pubsub:xmlel_event([
+                         exmpp_pubsub:xmlel_items('pubsub#event', NodeId,
+                             [exmpp_pubsub:xmlel_retract(ItemId)])
+                         ])
+                    ];
+                _SubIds ->
+                    [exmpp_pubsub:xmlel_event([
+                         exmpp_pubsub:xmlel_items('pubsub#event', NodeId,
+                             [exmpp_pubsub:xmlel_retract(ItemId)])
+                         ]),
+                     exmpp_pubsub:xmlel_headers(
+                         [exmpp_pubsub:xmlel_header(SubId) || SubId <- SubIds])
+                    ]
+            end)
+        ).
+
+
+broadcast_item(From, To, Stanza, SubIds) ->
+    ejabberd_router:route(From, To,
+        case SubIds of
+            [_] -> Stanza;
+            _   -> exmpp_xml:append_child(Stanza, shim_headers(SubIds))
+        end).
+
+
+shim_headers(SubIds) ->
+    ?Xmlel(?NS_SHIM, <<"headers">>, [],
+        [?Xmlel(?NS_SHIM, <<"header">>, [{<<"name">>, <<"SubID">>}], [?CData(SubId)])
+        || SubId <- SubIds]
+        ).
+
+%%
+xmlel_delay(From, DateTime) ->
+    {T_string, Tz_string} = jlib:timestamp_to_iso(
+        calendar:now_to_datetime(DateTime), 'utc'),
+    ?Xmlel(?NS_DELAY, <<"delay">>,
+        [{<<"from">>, pubsub_tools:jid_to_string(From)},
+         {<<"stamp">>, list_to_binary(T_string ++ Tz_string)}],
+        []).
+
+%%
+-spec(broadcast_publish/8 ::
+(
+  Host              :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host       :: exmpp_pubsub:host(),
+  NodeId            :: exmpp_pubsub:nodeId(),
+  Node_Options      :: pubsub_options:options_node(),
+  Node_Owners       :: [Node_Owner::xmpp_jid:usr_bare(),...],
+  Broadcasted_Items :: {
+    Published_Items :: [{
+      ItemId       :: exmpp_pubsub:itemId(),
+      Item_Options :: [] | pubsub_options:options_item(),
+      Payload      :: exmpp_pubsub:payload(),
+      Publisher    :: xmpp_jid:usr_entity()
+    }],
+    %
+    Retracted_Items :: [{
+      ItemId       :: exmpp_pubsub:itemId(),
+      Item_Options :: [] | pubsub_options:options_item()
+    }]
+  },
+  Subscription      :: undefined
+                     | {Subscriber         :: xmpp_jid:raw_jid_entity(),
+                        Subscription_State :: _,%exmpp_pubsub:subscription_state(),
+                        SubId              :: exmpp_pubsub:subId()},
+  Pubsub_States :: [Pubsub_State::mod_pubsub_dev:pubsub_state(),...])
+    -> 'ok'
+).
+
+broadcast_publish(Host, Pubsub_Host, NodeId, Node_Options, Node_Owners,
+  {Published_Items, Retracted_Items}, Subscription, Pubsub_States) ->
+    Event = #event{
+        host      = Host,
+        component = jlib:make_jid(<<>>, Pubsub_Host, <<>>),
+        node      = #node{
+            id                     = NodeId,
+            owners                 = Node_Owners,
+            access_model           = get_value(Node_Options, 'access_model'),
+            rosters_groups_allowed = get_value(Node_Options, 'roster_groups_allowed')
+        }
+    },
+    Broadcasted_Items = lists:map(fun
+        %%
+        ({ItemId, _Item_Options = []}) ->
+            #item{
+                presence_based_delivery = get_value(Node_Options,
+                    'presence_based_delivery'),
+                stanza = stanza_notify_retract(
+                    get_value(Node_Options, 'notification_type', 'headline'),
+                    NodeId, ItemId)
+            };
+        %%
+        ({ItemId, Item_Options}) ->
+            #item{
+                access_model = get_value(Item_Options, 'access_model', undefined),
+                presence_based_delivery = get_value({Node_Options, Item_Options},
+                    'presence_based_delivery'),
+                rosters_groups_allowed = get_value(Item_Options,
+                    'roster_groups_allowed', []),
+                stanza = stanza_notify_retract(
+                    get_value({Node_Options, Item_Options}, 'notification_type',
+                        'headline'),
+                    NodeId, ItemId)
+            };
+        %%
+        ({ItemId, _Item_Options = [], Payload, Publisher}) ->
+            #item{
+                presence_based_delivery = get_value(Node_Options,
+                    'presence_based_delivery'),
+                stanza = stanza_notify_publish(
+                    get_value(Node_Options, 'notification_type', 'headline'),
+                    NodeId,
+                    ItemId,
+                    _Publisher = case
+                        get_value(Node_Options, 'itemreply', 'owner')
+                    of
+                        'publisher' -> pubsub_tools:jid_to_string(Publisher);
+                       _Owner       -> undefined
+                    end,
+                    Payload)
+            };
+        %%
+        ({ItemId, Item_Options, Payload, Publisher}) ->
+            #item{
+                access_model = get_value(Item_Options, 'access_model'),
+                presence_based_delivery = get_value({Node_Options, Item_Options},
+                    'presence_based_delivery'),
+                rosters_groups_allowed = get_value(Item_Options,
+                    'roster_groups_allowed', []),
+                stanza = stanza_notify_publish(
+                    get_value({Node_Options, Item_Options}, 'notification_type',
+                        'headline'),
+                    NodeId,
+                    ItemId,
+                    _Publisher = case
+                        get_value({Node_Options, Item_Options}, 'itemreply',
+                            'owner')
+                    of
+                        'publisher' -> pubsub_tools:jid_to_string(Publisher);
+                       _Owner       -> undefined
+                    end,
+                    Payload)
+            }
+        %  
+    end, lists:append(Retracted_Items, Published_Items)),
+    %
+    lists:foreach(fun
+        %%
+        (#pubsub_state_dev{id = {{U,S,R} = _Entity, _NodeIdx},
+         affiliation = Affiliation, subscriptions = Subscriptions})
+          when   (Affiliation == 'member'
+          orelse  Affiliation == 'owner'
+          orelse  Affiliation == 'publisher')
+          andalso Subscriptions =/= [] ->
+            case Subscription =/= undefined andalso Affiliation == 'owner' of
+                true ->
+                    notify_subscription(Host, NodeId,
+                        _Pubsub_Component_Jid = Event#event.component,
+                        _Recipient = jlib:make_jid(U,S,<<>>),
+                        _Notification_Type = get_value(Node_Options,
+                            'notification_type'),
+                         Subscription);
+                false ->
+                    ok
+            end,
+            lists:foldl(fun broadcast_item/2,
+                Event#event{
+                    entity = #entity{
+                        id            = {U,S,R},
+                        local         = S == Event#event.host,
+                        affiliation   = Affiliation,
+                        subscriptions = Subscriptions
+                    },
+                    cache  = #cache{},
+                    subids = #subids{}
+                },
+                Broadcasted_Items);
+        %%
+        (_Pubsub_State) ->
+            ok
+        %
+    end, Pubsub_States).
+
+%%
+
+-spec(broadcast_publish_last/9 ::
+(
+  Host            :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host     :: exmpp_pubsub:host(),
+  NodeId          :: exmpp_pubsub:nodeId(),
+  Node_Options    :: pubsub_options:options_node(),
+  Node_Owners     :: [Node_Owner::xmpp_jid:usr_bare(),...],
+  Published_Items :: [Published_Item :: {
+      ItemId       :: exmpp_pubsub:itemId(),
+      Item_Options :: [] | pubsub_options:options_item(),
+      Payload      :: exmpp_pubsub:payload(),
+      Publisher    :: xmpp_jid:usr_entity(),
+      DateTime     :: erlang:timestamp()
+  },...],
+  Entity          :: xmpp_jid:usr_entity(),
+  Affiliation     :: 'member' | 'owner' | 'publisher',
+  Subscription    :: exmpp_pubsub:subscription())
+    -> none()
+).
+
+broadcast_publish_last(Host, Pubsub_Host, NodeId, Node_Options, Node_Owners,
+  Published_Items, {U,S,R} = Entity, Affiliation, Subscription) ->
+    Event = #event{
+        host      = Host,
+        component = jlib:make_jid(<<>>, Pubsub_Host, <<>>),
+        node      = #node{
+            id                     = NodeId,
+            owners                 = Node_Owners,
+            access_model           = get_value(Node_Options, 'access_model'),
+            rosters_groups_allowed = get_value(Node_Options, 'roster_groups_allowed')
+        }
+    },
+    Broadcasted_Items = lists:map(fun
+        %%
+        ({ItemId, _Item_Options = [], Payload, Publisher, DateTime}) ->
+            #item{
+                presence_based_delivery = get_value(Node_Options,
+                    'presence_based_delivery'),
+                stanza = exmpp_xml:append_child(stanza_notify_publish(
+                    get_value(Node_Options, 'notification_type', 'headline'),
+                    NodeId,
+                    ItemId,
+                    _Publisher = case
+                        get_value(Node_Options, 'itemreply', 'owner')
+                    of
+                        'publisher' -> pubsub_tools:jid_to_string(Publisher);
+                       _Owner       -> undefined
+                    end,
+                    Payload),
+                    xmlel_delay(Publisher, DateTime))
+            };
+        %%
+        ({ItemId, Item_Options, Payload, Publisher, DateTime}) ->
+            #item{
+                access_model = get_value(Item_Options, 'access_model'),
+                presence_based_delivery = get_value({Node_Options, Item_Options},
+                    'presence_based_delivery'),
+                rosters_groups_allowed = get_value(Item_Options,
+                    'roster_groups_allowed', []),
+                stanza = exmpp_xml:append_child(stanza_notify_publish(
+                    get_value({Node_Options, Item_Options}, 'notification_type',
+                        'headline'),
+                    NodeId,
+                    ItemId,
+                    _Publisher = case
+                        get_value({Node_Options, Item_Options}, 'itemreply',
+                            'owner')
+                    of
+                        'publisher' -> pubsub_tools:jid_to_string(Publisher);
+                       _Owner       -> undefined
+                    end,
+                    Payload),
+                    xmlel_delay(Publisher, DateTime))
+            }
+        %  
+    end, Published_Items),
+    case get_value(Node_Options, 'notify_sub', false) of
+        true ->
+            {Subscription_State, SubId, Resource, _} = Subscription,
+            Subscriber = pubsub_tools:jid_to_string({U,S,Resource}),
+            Notification_Type = get_value(Node_Options, 'notification_type',
+                'headline'),
+            lists:foreach(fun
+                (Node_Owner) ->
+                    notify_subscription(Host, NodeId,
+                        _Pubsub_Component_Jid = Event#event.component,
+                        _Recipient = pubsub_tools:make_jid(Node_Owner),
+                        Notification_Type,
+                         {Subscriber, Subscription_State, SubId})
+            
+            end, Node_Owners);
+        false ->
+            ok
+    end,
+    %%
+    lists:foldl(fun broadcast_item/2,
+        Event#event{
+            entity = #entity{
+                id            = {U,S,R},
+                local         = S == Event#event.host,
+                affiliation   = Affiliation,
+                subscriptions = [Subscription]
+            },
+            cache  = #cache{},
+            subids = #subids{}
+        },
+        Broadcasted_Items).
+
+
+-spec(broadcast_publish_last2/9 ::
+(
+  Host            :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host     :: exmpp_pubsub:host(),
+  NodeId          :: exmpp_pubsub:nodeId(),
+  Node_Options    :: pubsub_options:options_node(),
+  Node_Owners     :: [Node_Owner::xmpp_jid:usr_bare(),...],
+  Published_Items :: [Published_Item :: {
+      ItemId       :: exmpp_pubsub:itemId(),
+      Item_Options :: [] | pubsub_options:options_item(),
+      Payload      :: exmpp_pubsub:payload(),
+      Publisher    :: xmpp_jid:usr_entity(),
+      DateTime     :: erlang:timestamp()
+  },...],
+  Entity          :: xmpp_jid:usr_entity(),
+  Affiliation     :: 'member' | 'owner' | 'publisher',
+  Subscriptions    :: exmpp_pubsub:subscription())
+    -> none()
+).
+
+broadcast_publish_last2(Host, Pubsub_Host, NodeId, Node_Options, Node_Owners,
+  Published_Items, {U,S,R} = Entity, Affiliation, Subscriptions) ->
+    Event = #event{
+        host      = Host,
+        component = jlib:make_jid(<<>>, Pubsub_Host, <<>>),
+        node      = #node{
+            id                     = NodeId,
+            owners                 = Node_Owners,
+            access_model           = get_value(Node_Options, 'access_model'),
+            rosters_groups_allowed = get_value(Node_Options, 'roster_groups_allowed')
+        }
+    },
+    Broadcasted_Items = lists:map(fun
+        %%
+        ({ItemId, _Item_Options = [], Payload, Publisher, DateTime}) ->
+            #item{
+                presence_based_delivery = get_value(Node_Options,
+                    'presence_based_delivery'),
+                stanza = exmpp_xml:append_child(stanza_notify_publish(
+                    get_value(Node_Options, 'notification_type', 'headline'),
+                    NodeId,
+                    ItemId,
+                    _Publisher = case
+                        get_value(Node_Options, 'itemreply', 'owner')
+                    of
+                        'publisher' -> pubsub_tools:jid_to_string(Publisher);
+                       _Owner       -> undefined
+                    end,
+                    Payload),
+                    xmlel_delay(Publisher, DateTime))
+            };
+        %%
+        ({ItemId, Item_Options, Payload, Publisher, DateTime}) ->
+            #item{
+                access_model = get_value(Item_Options, 'access_model'),
+                presence_based_delivery = get_value({Node_Options, Item_Options},
+                    'presence_based_delivery'),
+                rosters_groups_allowed = get_value(Item_Options,
+                    'roster_groups_allowed', []),
+                stanza = exmpp_xml:append_child(stanza_notify_publish(
+                    get_value({Node_Options, Item_Options}, 'notification_type',
+                        'headline'),
+                    NodeId,
+                    ItemId,
+                    _Publisher = case
+                        get_value({Node_Options, Item_Options}, 'itemreply',
+                            'owner')
+                    of
+                        'publisher' -> pubsub_tools:jid_to_string(Publisher);
+                       _Owner       -> undefined
+                    end,
+                    Payload),
+                    xmlel_delay(Publisher, DateTime))
+            }
+        %  
+    end, Published_Items),
+    %%
+    lists:foldl(fun broadcast_item/2,
+        Event#event{
+            entity = #entity{
+                id            = {U,S,R},
+                local         = S == Event#event.host,
+                affiliation   = Affiliation,
+                subscriptions = Subscriptions
+            },
+            cache  = #cache{},
+            subids = #subids{}
+        },
+        Broadcasted_Items).
+
+%%
+-define(Resources_Subids(Item, Event),
+    (Item#item.presence_based_delivery == false
+         andalso
+     Event#event.subids#subids.no_presence =/= undefined
+         andalso
+     Event#event.subids#subids.no_presence =/= [])
+             orelse
+    (Item#item.presence_based_delivery == true
+         andalso
+     Event#event.subids#subids.presence =/= undefined
+         andalso
+    Event#event.subids#subids.presence =/= [])
+).
+
+-define(Item_Access_Model(Item, Event),
+    Item#item.access_model == undefined
+        orelse
+    Item#item.access_model == 'open'
+        orelse
+    Item#item.access_model == 'authorize'
+        orelse
+    Item#item.access_model == 'whitelist'
+        orelse
+    (Item#item.access_model == Event#event.node#node.access_model
+                 andalso
+     Item#item.access_model =/= 'roster')
+        orelse
+    (Item#item.access_model == 'presence'
+            andalso
+           (Event#event.entity#entity.affiliation == 'owner'
+                orelse
+%            Event#event.entity#entity.affiliation == 'publisher'
+%                orelse
+            Event#event.node#node.access_model == 'presence'
+                orelse
+            Event#event.node#node.access_model == 'roster'
+                orelse
+            Event#event.cache#cache.presence_subscriptions == true)
+          )
+        orelse
+    (Item#item.access_model == 'roster'
+            andalso
+           (Event#event.entity#entity.affiliation == 'owner'
+                orelse
+            Event#event.entity#entity.affiliation == 'publisher'
+                orelse
+            Event#event.cache#cache.rosters_groups == true)
+          )
+).
+
+
+-define(Broadcast_Event(Item, Event),
+  (?Resources_Subids(Item, Event)) and (?Item_Access_Model(Item, Event))
+).
+
+-define(Presence_Based_Delivery(Item, Event),
+    Item#item.presence_based_delivery == true
+        andalso
+    Event#event.subids#subids.presence == undefined
+).
+
+-define(No_Presence_Based_Delivery(Item, Event),
+    Item#item.presence_based_delivery == false
+        andalso
+    Event#event.subids#subids.no_presence == undefined
+).
+
+-define(Presence_Based_Delivery_Cache(Item, Event),
+    Item#item.presence_based_delivery == true
+        andalso
+    Event#event.cache#cache.presence == undefined
+).
+
+-define(Item_Access_Model_Presence(Item, Event),
+  Item#item.access_model == 'presence'
+      andalso
+  Event#event.cache#cache.presence_subscriptions == undefined
+).
+
+-define(Item_Access_Model_Roster(Item, Event),
+  Item#item.access_model == 'roster'
+      andalso
+  Event#event.cache#cache.rosters_groups == undefined
+).
+
+
+-spec(broadcast_item/2 ::
+(
+  Item  :: mod_pubsub_dev:item(),
+  Event :: mod_pubsub_dev:event())
+    -> Event::mod_pubsub_dev:event()
+%      Event::#event{cache::#cache{rosters_groups :: undefined}}
+).
+
+
+
+%%
+broadcast_item(#item{stanza = Stanza} = Item, 
+  #event{entity = #entity{id = {U,S,_R}}} = Event)
+  when ?Broadcast_Event(Item, Event) ->
+    lists:foreach(fun
+        ({Resource, SubIds}) ->
+            broadcast_item(_From = Event#event.component,
+                _To = jlib:make_jid(U,S,Resource),
+                Stanza,
+                SubIds)
+    end,
+        _Resources_SubIds = case Item#item.presence_based_delivery of
+            true  -> Event#event.subids#subids.presence;
+            false -> Event#event.subids#subids.no_presence
+        end),
+    Event#event{cache = Event#event.cache#cache{rosters_groups = undefined}};
+%%
+broadcast_item(Item, Event)
+  when ?No_Presence_Based_Delivery(Item, Event) ->
+    {Presence_Cache, Resources_SubIds} = resources_subids(
+        _Entity = Event#event.entity#entity.id,
+        _Local_Entity = Event#event.entity#entity.local,
+        _Presence_Based_Delivery = false,
+        _Subscriptions = Event#event.entity#entity.subscriptions,
+        {Event#event.cache#cache.presence, []}),
+    case Resources_SubIds of
+        [] ->
+            Event#event{
+                cache = Event#event.cache#cache{
+                    presence = Presence_Cache,
+                    rosters_groups = undefined
+                },
+                subids = Event#event.subids#subids{
+                    no_presence = []
+                }
+            };
+        _Resources_SubIds ->
+            broadcast_item(Item,
+                Event#event{
+                    cache = Event#event.cache#cache{
+                        presence = Presence_Cache
+                    },
+                    subids = Event#event.subids#subids{
+                        no_presence = Resources_SubIds
+                    }
+                }
+            )
+    end;
+%%
+broadcast_item(Item, #event{entity = #entity{id = {U,S,_R}}} = Event)
+  when ?Presence_Based_Delivery_Cache(Item, Event) ->
+    case get_resources_show(U,S) of
+        [] ->
+            Event#event{
+                cache = Event#event.cache#cache{
+                    presence = [],
+                    rosters_groups = undefined
+                }
+            };
+        Resources_Show ->
+            broadcast_item(Item,
+                Event#event{
+                    cache = Event#event.cache#cache{
+                        presence = Resources_Show
+                    }
+                })
+    end;
+%%
+broadcast_item(Item, Event)
+  when ?Presence_Based_Delivery(Item, Event) ->
+    {Presence_Cache, Resources_SubIds} = resources_subids(
+        _Entity = Event#event.entity#entity.id,
+        _Local_Entity = Event#event.entity#entity.local,
+        _Presence_Based_Delivery = true,
+        _Subscriptions = Event#event.entity#entity.subscriptions,
+        {Event#event.cache#cache.presence, []}),
+    case Resources_SubIds of
+        [] ->
+            Event#event{
+                cache = Event#event.cache#cache{
+                    presence = Presence_Cache,
+                    rosters_groups = undefined
+                },
+                subids = Event#event.subids#subids{
+                    presence = []}
+            };
+        _Resources_SubIds ->
+            broadcast_item(Item,
+                Event#event{
+                    cache = Event#event.cache#cache{
+                        presence = Presence_Cache
+                    },
+                    subids = Event#event.subids#subids{
+                        presence = Resources_SubIds
+                    }
+                })
+    end;
+%%
+broadcast_item(Item, Event)
+  when ?Item_Access_Model_Presence(Item, Event) ->
+    case
+        is_contact_subscribed_to_node_owners(
+            _Host = Event#event.host,
+            _Entity = Event#event.entity#entity.id,
+            _Node_Owners = Event#event.node#node.owners
+        )
+    of
+        false ->
+            Event#event{
+                cache = Event#event.cache#cache{
+                    presence_subscriptions = false,
+                    rosters_groups = undefined
+                }
+            };
+        _Node_Owner ->
+            broadcast_item(Item,
+                Event#event{
+                    cache = Event#event.cache#cache{
+                        presence_subscriptions = true
+                    }
+                }
+            )
+    end;
+%%
+broadcast_item(Item, Event)
+  when ?Item_Access_Model_Roster(Item, Event) ->
+    case Event#event.node#node.access_model of
+        'roster' ->
+            case Item#item.rosters_groups_allowed of
+                %%
+                [] ->
+                    broadcast_item(Item,
+                        Event#event{
+                            cache = Event#event.cache#cache{
+                                rosters_groups = true
+                            }
+                        }
+                    );
+                %%
+                Item_Rosters_Groups_Allowed ->
+                    case
+                        is_contact_in_allowed_roster_groups(
+                            _Contact = Event#event.entity#entity.id,
+                            _Rosters_Groups_Allowed = Item_Rosters_Groups_Allowed
+                        )
+                    of
+                        false ->
+                            Event;
+                        {_Node_Owner, _Roster_Group_Allowed} ->
+                            broadcast_item(Item,
+                                Event#event{
+                                    cache = Event#event.cache#cache{
+                                        rosters_groups = true
+                                    }
+                                })
+                    end
+            end;
+        _Node_Access_Model ->
+            case
+                is_contact_in_allowed_roster_groups(
+                    _Contact = Event#event.entity#entity.id,
+                    _Rosters_Groups_Allowed = case
+                        Item#item.rosters_groups_allowed
+                    of
+                        [] ->
+                            Event#event.node#node.rosters_groups_allowed;
+                        Item_Rosters_Groups_Allowed ->
+                            Item_Rosters_Groups_Allowed
+                    end
+                )
+            of
+                false ->
+                    Event;
+                {_Node_Owner, _Roster_Group_Allowed} ->
+                    broadcast_item(Item,
+                        Event#event{
+                            cache = Event#event.cache#cache{rosters_groups = true}
+                        })
+            end
+    end;
+%%
+broadcast_item(_Item, Event) ->
+    Event#event{cache = Event#event.cache#cache{rosters_groups = undefined}}.
+
+
+%%
+-spec(resources_subids/5 ::
+(
+  Entity                  :: xmpp_jid:usr_bare(),
+  Local_Entity            :: boolean(),
+  Presence_Based_Delivery :: boolean(),
+  Subscriptions           :: _,%exmpp_pubsub:subscriptions() | [],
+  Cache                   :: {
+    Presence_Cache   :: undefined | [] | mod_pubsub_dev:presence_cache(),
+    Resources_SubIds :: undefined | [] | mod_pubsub_dev:resources_subids()
+  })
+    -> {Presence_Cache   :: undefined | [] | mod_pubsub_dev:presence_cache(),
+        Resources_SubIds :: [] | mod_pubsub_dev:resources_subids()}
+).
+
+resources_subids(_Entity, _Local_Entity, _Presence_Based_Delivery,
+  [] = _Subscriptions, {Presence_Cache, Resources_SubIds}) ->
+    {Presence_Cache, Resources_SubIds};
+%%
+resources_subids(Entity, Local_Entity, Presence_Based_Delivery,
+  [{'pending', _SubId, _Resource, _Subscription_Options} | Subscriptions],
+  {Presence_Cache, Resources_SubIds}) ->
+    resources_subids(Entity, Local_Entity, Presence_Based_Delivery, Subscriptions,
+        {Presence_Cache, Resources_SubIds});
+%%
+resources_subids(Entity, Local_Entity, Presence_Based_Delivery,
+  [{Subscription_State, SubId, {caps, Resource}, Subscription_Options}
+  | Subscriptions], {Presence_Cache, Resources_SubIds}) ->
+    resources_subids(Entity, Local_Entity, Presence_Based_Delivery,
+        [{Subscription_State, SubId, Resource, Subscription_Options}
+        | Subscriptions],
+        {Presence_Cache, Resources_SubIds});
+%% Presence_Based_Delivery = false
+%% Local_Entity = boolean()
+%% Subscription_Options = []
+resources_subids(Entity, Local_Entity, false = Presence_Based_Delivery,
+  [{_Subscription_State, SubId, Resource, [] = _Subscription_Options}
+  | Subscriptions], {Presence_Cache, Resources_SubIds}) ->
+    resources_subids(Entity, Local_Entity, Presence_Based_Delivery, Subscriptions,
+        {Presence_Cache,
+         _Resources_SubIds = resources_subids(Resource, SubId,
+             Resources_SubIds)});
+%% Presence_Based_Delivery = false
+%% Local_Entity = true
+%% Resource = undefined | xmpp_jid:resource_jid()
+%% Subscription_Options =/= []
+resources_subids({U,S,R} = _Entity, true = Local_Entity, false = Presence_Based_Delivery,
+  [{_Subscription_State, SubId, Resource, Subscription_Options} | Subscriptions],
+  {Presence_Cache, Resources_SubIds}) ->
+    resources_subids({U,S,R}, Local_Entity, Presence_Based_Delivery,
+       Subscriptions,
+        case get_value(Subscription_Options, 'deliver', true) of
+            true ->
+                case get_value(Subscription_Options, 'show-values') of
+                    'none' -> %% 'show-values' NA 
+                        {Presence_Cache,
+                         _Resources_SubIds = resources_subids(Resource, SubId,
+                             Resources_SubIds)};
+                    %%
+                    Show_Values
+                      when   Show_Values == []
+                      orelse Presence_Cache == [] ->
+                        {Presence_Cache, Resources_SubIds};
+                    %%
+                    Show_Values
+                      when Presence_Cache == undefined ->
+                        case get_resources_show(U, S) of
+                            %%%%
+                            [] ->
+                                {_Presence_Cache = [], Resources_SubIds};
+                            %%%%
+                            Resources_Show ->
+                                {_Presence_Cache = Resources_Show,
+                                 _Resources_SubIds = lists:foldl(fun
+                                    (Resource_To_Deliver, Resources_SubIds_Bis) ->
+                                        resources_subids(Resource_To_Deliver,
+                                            SubId, Resources_SubIds_Bis)
+                                 end,
+                                    Resources_SubIds,
+                                    _Resources_To_Deliver = resources_to_deliver(
+                                        Resource, Show_Values, Resources_Show,
+                                            []))}
+                        end;
+                    %%
+                    Show_Values ->
+                        {Presence_Cache,
+                         _Resources_SubIds = lists:foldl(fun
+                            (Resource_To_Deliver, Resources_SubIds_Bis) ->
+                                resources_subids(Resource_To_Deliver,
+                                    SubId, Resources_SubIds_Bis)
+                         end,
+                            Resources_SubIds,
+                            _Resources_To_Deliver = resources_to_deliver(
+                                Resource, Show_Values, Presence_Cache, []))}
+                end;
+            false ->
+                {Presence_Cache, Resources_SubIds}
+        end);
+%% Presence_Based_Delivery = false
+%% Local_Entity = false
+%% Subscription_Options =/= []
+resources_subids(Entity, false = Local_Entity, false = Presence_Based_Delivery,
+  [{_Subscription_State, SubId, Resource, Subscription_Options} | Subscriptions],
+  {Presence_Cache, Resources_SubIds}) ->
+    resources_subids(Entity, Local_Entity, Presence_Based_Delivery, Subscriptions,
+        case get_value(Subscription_Options, 'deliver', true) of
+            true ->
+                {Presence_Cache,
+                 _Resources_SubIds = resources_subids(Resource, SubId,
+                     Resources_SubIds)};
+            false ->
+                {Presence_Cache, Resources_SubIds}
+        end);
+%% Presence_Based_Delivery = true
+%% Local_Entity = true
+%% Subscription_Options : NA
+%% Presence_Cache = 'none'
+resources_subids({U,S,R} = _Entity, true = _Local_Entity,
+  true = _Presence_Based_Delivery, Subscriptions,
+  {undefined = _Presence_Cache, Resources_SubIds}) ->
+    case get_resources_show(U, S) of
+        [] ->
+            {[], Resources_SubIds};
+        _Resources_Show = Presence_Cache ->
+            resources_subids({U,S,R}, true, true, Subscriptions,
+               {Presence_Cache, Resources_SubIds})
+    end;
+%% Presence_Based_Delivery = true
+%% Local_Entity = true
+%% Subscription_Options : NA
+%% Presence_Cache = []
+resources_subids(_Entity, true = _Local_Entity, true = _Presence_Based_Delivery,
+  _Subscriptions, {[] = Presence_Cache, Resources_SubIds}) ->
+    {Presence_Cache, Resources_SubIds};
+%% Presence_Based_Delivery = true
+%% Local_Entity = true
+%% Resource = undefined | xmpp_jid:resource_jid()
+%% Subscription_Options =/= []
+%% Presence_Cache =/= []
+resources_subids(Entity, true = _Local_Entity, true = Presence_Based_Delivery,
+  [{_Subscription_State, SubId, Resource, Subscription_Options} | Subscriptions],
+  {Presence_Cache, Resources_SubIds}) ->
+    resources_subids(Entity, true, Presence_Based_Delivery, Subscriptions,
+        case
+            get_value(Subscription_Options, 'deliver', true) == true
+                andalso
+            (Resource == undefined
+                     orelse lists:keymember(Resource, 1, Presence_Cache))
+        of
+            true ->
+                {Presence_Cache,
+                 _Resources_SubIds = case
+                     get_value(Subscription_Options, 'show-values')
+                 of
+                    'none' when Resource == undefined -> %% 'show-values' NA
+                        lists:foldl(fun
+                            ({Resource_To_Deliver, _Show}, Resources_SubIds_Bis) ->
+                                resources_subids(Resource_To_Deliver,
+                                    SubId, Resources_SubIds_Bis)
+                        end, Resources_SubIds, Presence_Cache);
+                    'none' -> %% 'show-values' NA
+                        resources_subids(Resource, SubId, Resources_SubIds);
+                    [] ->
+                        Resources_SubIds;
+                    Show_Values ->
+                        lists:foldl(fun
+                             (Resource_To_Deliver, Resources_SubIds_Bis) ->
+                                 resources_subids(Resource_To_Deliver,
+                                     SubId, Resources_SubIds_Bis)
+                         end,
+                             Resources_SubIds,
+                                 _Resources_To_Deliver = resources_to_deliver(
+                                     Resource, Show_Values, Presence_Cache, []))
+                 end};
+            false ->
+                {Presence_Cache, Resources_SubIds}
+        end);
+%% Presence_Based_Delivery = true
+%% Local_Entity = false
+%% Subscription_Options : NA
+resources_subids(_Entity, false = _Local_Entity, true = _Presence_Based_Delivery,
+  _Subscriptions, {Presence_Cache, Resources_SubIds}) ->
+      {Presence_Cache, Resources_SubIds}.
+
+%%
+-spec(resources_subids/3 ::
+(
+  Resource         :: xmpp_jid:resource_jid(),
+  SubId            :: exmpp_pubsub:subId(),
+  Resources_SubIds :: [] | mod_pubsub_dev:resources_subids())
+    -> %%
+       Resources_SubIds::mod_pubsub_dev:resources_subids()
+).
+
+resources_subids(Resource, SubId, Resources_SubIds) ->
+    _Resources_SubIds = case lists:keyfind(Resource, 1, Resources_SubIds) of
+        {_Resource, SubIds} ->
+            lists:keyreplace(Resource, 1, Resources_SubIds,
+                {Resource, [SubId | SubIds]});
+        false ->
+            [{Resource, [SubId]} | Resources_SubIds]
+    end.
+
+%%
+-spec(resources_to_deliver/4 ::
+(
+  Resource       :: undefined | xmpp_jid:resource_jid(),
+  Show_Values    :: ['away' | 'chat' | 'dnd' | 'online' | 'xa',...],
+  Presence_Cache :: [] | mod_pubsub_dev:presence_cache(),
+  Resources_To_Deliver :: [Resource::xmpp_jid:resource_jid()])
+    -> %%
+       Resources_To_Deliver::[Resource::xmpp_jid:resource_jid()]
+).
+
+resources_to_deliver(_Resource, _Show_Values, [] = _Presence_Cache,
+  Resources_To_Deliver) ->
+    Resources_To_Deliver;
+%%
+resources_to_deliver(Resource, Show_Values, [Resource_Show | Presence_Cache],
+  Resources_To_Deliver) ->
+    resources_to_deliver(Resource, Show_Values, Presence_Cache,
+        _Resources_To_Deliver = resource_to_deliver(Resource, Show_Values,
+            Resource_Show, Resources_To_Deliver)).
+
+%%
+-spec(resource_to_deliver/4 ::
+(
+  Resource      :: undefined | xmpp_jid:resource_jid(),
+  Show_Values   :: ['away' | 'chat' | 'dnd' | 'online' | 'xa',...],
+  Resource_Show :: mod_pubsub_dev:resource_show(),
+  Resources_To_Deliver :: [Resource::xmpp_jid:resource_jid()])
+    -> %%
+       Resources_To_Deliver::[Resource::xmpp_jid:resource_jid()]
+).
+
+resource_to_deliver(_Resource, [] = _Show_Values, _Resource_Show,
+  Resources_To_Deliver) ->
+    Resources_To_Deliver;
+%%
+resource_to_deliver(undefined = _Resource, [_Show_Value = Show | Show_Values],
+  {Resource, Show}, Resources_To_Deliver) ->
+    resource_to_deliver(_Resource = undefined, Show_Values, {Resource, Show},
+        [_Resource_To_Deliver = Resource | Resources_To_Deliver]);
+%%
+resource_to_deliver(Resource, [_Show_Value = Show | Show_Values],
+  {Resource, Show}, Resources_To_Deliver) ->
+    resource_to_deliver(Resource, Show_Values, {Resource, Show},
+        [_Resource_To_Deliver = Resource | Resources_To_Deliver]);
+%%
+resource_to_deliver(Resource, [_Show_Value | Show_Values], Resource_Show,
+  Resources_To_Deliver) ->
+    resource_to_deliver(Resource, Show_Values, Resource_Show,
+        Resources_To_Deliver).
+
diff --git a/src/mod_pubsub_ng/pubsub_core.erl b/src/mod_pubsub_ng/pubsub_core.erl
new file mode 100644
index 000000000..8914987f9
--- /dev/null
+++ b/src/mod_pubsub_ng/pubsub_core.erl
@@ -0,0 +1,1707 @@
+%%% ====================================================================
+%%% ``The contents of this file are subject to the Erlang Public License,
+%%% Version 1.1, (the "License"); you may not use this file except in
+%%% compliance with the License. You should have received a copy of the
+%%% Erlang Public License along with this software. If not, it can be
+%%% retrieved via the world wide web at http://www.erlang.org/.
+%%% 
+%%% Software distributed under the License is distributed on an "AS IS"
+%%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%%% the License for the specific language governing rights and limitations
+%%% under the License.
+%%% 
+%%% The Initial Developer of the Original Code is ProcessOne.
+%%% Portions created by ProcessOne are Copyright 2006-2011, ProcessOne
+%%% All Rights Reserved.''
+%%% This software is copyright 2006-2011, ProcessOne.
+%%%
+%%% @copyright 2006-2011 ProcessOne
+%%% @author Karim Gemayel <karim.gemayel@process-one.net>
+%%%   [http://www.process-one.net/]
+%%% @version {@vsn}, {@date} {@time}
+%%% @end
+%%% ====================================================================
+
+%%% @headerfile "pubsub_dev.hrl"
+
+-module(pubsub_core).
+-author('karim.gemayel@process-one.net').
+
+-compile(export_all).
+
+-include("pubsub_dev.hrl").
+-include("pubsub_api.hrl").
+
+-import(pubsub_tools,
+[
+  is_jid/1,
+  get_option/2,
+  get_option/3,
+  get_value/2,
+  get_value/3,
+  set_value/3,
+  %%
+  check_access_model/3,
+  check_access_model/7,
+  check_publish_model/3,
+  is_contact_subscribed_to_node_owners/3,
+  is_contact_in_allowed_roster_groups/2,
+  has_subscriptions/1
+]).
+
+
+
+-spec(features/3 ::
+(
+  Function        :: 'create_node'
+                   | 'purge_node'
+                   | 'publish_item'
+                   | 'retract_item'
+                   | 'get_items'
+                   | 'subscribe_node'
+                   | 'get_configure_subscription_default'
+                   | 'get_configure_node_default',
+  Pubsub_Features :: exmpp_pubsub:pubsub_features(),
+  Criteria        :: %-- Create_Node --%
+                     {NodeId      :: undefined | exmpp_pubsub:nodeId(),
+                      Node_Config :: [] | [Xmlel::xmlel(),...]}
+                  %% %-- Purge_Node --%
+                   | 'none'
+                  %% %-- Publish_Item --%
+                   | {NodeId          :: undefined | exmpp_pubsub:nodeId(),
+                      Node_Config     :: [] | [Xmlel::xmlel(),...],
+                      Publish_Options :: [] | [Xmlel::xmlel(),...]}
+                  %% %-- Retract_Item --%
+                   | 'none'
+                  %% %-- Get_Items --%
+                   | 'none'
+                  %% %-- Subscribe_Node --%
+                   | {Subscribe_Options :: [Xmlel::xmlel()]}
+                  %% %-- Get_Configure_Subscription_Default --%
+                   | 'none'
+                  %% %-- Get_Configure_Node_Default --%
+                   | 'none'
+                   )
+    -> ok
+    %%%
+     %-- Create_Node --%
+     | {error, 'feature-not-implemented', 'create-nodes'}
+     | {error, 'feature-not-implemented', 'create-and-configure'}
+     %
+     | {error, 'not-acceptable', 'nodeid-required'}
+     %-- Purge_Node --%
+     | {error, 'feature-not-implemented', 'purge-nodes'}
+     | {error, 'feature-not-implemented', 'persistent-items'}
+     %-- Publish_Item --%
+     | {error, 'feature-not-implemented', 'publish'}
+     | {error, 'feature-not-implemented', 'auto-create'}
+     | {error, 'feature-not-implemented', 'config-node'}
+     | {error, 'feature-not-implemented', 'publish-options'}
+     %-- Retract_Item --%
+     | {error, 'feature-not-implemented', 'delete-items'}
+     | {error, 'feature-not-implemented', 'persistent-items'}
+     %-- Get_Items --%
+     | {error, 'feature-not-implemented', 'retrieve-items'}
+     | {error, 'feature-not-implemented', 'persistent-items'}
+     %-- Subscribe_Node --%
+     | {error, 'feature-not-implemented', 'subscribe'}
+     | {error, 'feature-not-implemented', 'subscription-options'}
+     %-- Get_Configure_Subscription_Default --%
+     | {error, 'feature-not-implemented', 'subscription-options'}
+     | {error, 'feature-not-implemented', 'retrieve-default-sub'}
+     %-- Get_Configure_Node_Default --%
+     | {error, 'feature-not-implemented', 'config-node'}
+     | {error, 'feature-not-implemented', 'retrieve-default'}
+).
+
+%-- Create_Node --%
+features('create_node', Pubsub_Features, {NodeId, [] = _Node_Config}) ->
+    case lists:member(<<"create-nodes">>, Pubsub_Features) of
+        true when NodeId =/= undefined ->
+            ok;
+        true ->
+            case lists:member(<<"instant-nodes">>, Pubsub_Features) of
+                true ->
+                    ok;
+                false ->
+                    {error, 'not-acceptable', 'nodeid-required'}
+            end;
+        false ->
+            {error, 'feature-not-implemented', 'create-nodes'}
+    end;
+%
+features('create_node', Pubsub_Features, {NodeId, _Node_Config}) ->
+    case features('create_node', Pubsub_Features, {NodeId, []}) of
+        ok ->
+            case lists:member(<<"create-and-configure">>, Pubsub_Features) of
+                true ->
+                    ok;
+                false ->
+                    {error, 'feature-not-implemented', 'create-and-configure'}
+            end;
+        Error ->
+            Error
+    end;
+%-- Purge_Node --%
+features('purge_node', Pubsub_Features, none) ->
+    case lists:member(<<"purge-nodes">>, Pubsub_Features) of
+        true ->
+            case lists:member(<<"persistent-items">>, Pubsub_Features) of
+                true ->
+                    ok;
+                false ->
+                    {error, 'feature-not-implemented', 'persistent-items'}
+            end;
+        false ->
+            {error, 'feature-not-implemented', 'purge-nodes'}
+    end;
+%-- Publish_Item --%
+features('publish_item', Pubsub_Features,
+  {NodeId, [] = _Node_Config, [] = _Publish_Options}) ->
+    case lists:member(<<"publish">>, Pubsub_Features) of
+        true when NodeId =/= undefined ->
+            ok;
+        true ->
+            case lists:member(<<"auto-create">>, Pubsub_Features) of
+                true ->
+                    ok;
+                false ->
+                    {error, 'feature-not-implemented', 'auto-create'}
+            end;
+        false ->
+            {error, 'feature-not-implemented', 'publish'}
+    end;
+%%
+features('publish_item', Pubsub_Features,
+  {NodeId, _Node_Config, [] = _Publish_Options}) ->
+    case features('publish_item', Pubsub_Features, {NodeId, [], []}) of
+        ok ->
+            case lists:member(<<"config-node">>, Pubsub_Features) of
+                true ->
+                    ok;
+                false ->
+                    {error, 'feature-not-implemented', 'config-node'}
+            end;
+        Error ->
+            Error
+    end;
+%
+features('publish_item', Pubsub_Features,
+  {NodeId, Node_Config, _Publish_Options}) ->
+    case features('publish_item', Pubsub_Features, {NodeId, Node_Config, []}) of
+        ok ->
+            case lists:member(<<"publish-options">>, Pubsub_Features) of
+                true ->
+                    ok;
+                false ->
+                    {error, 'feature-not-implemented', 'publish-options'}
+            end;
+        Error ->
+            Error
+    end;
+%-- Purge_Node --%
+features('retract_item', Pubsub_Features, none) ->
+    case lists:member(<<"delete-items">>, Pubsub_Features) of
+        true ->
+            case lists:member(<<"persistent-items">>, Pubsub_Features) of
+                true ->
+                    ok;
+                false ->
+                    {error, 'feature-not-implemented', 'persistent-items'}
+            end;
+        false ->
+            {error, 'feature-not-implemented', 'delete-items'}
+    end;
+%-- Get_Items --%
+features('get_items', Pubsub_Features, none) ->
+    case lists:member(<<"retrieve-items">>, Pubsub_Features) of
+        true ->
+            case lists:member(<<"persistent-items">>, Pubsub_Features) of
+                true ->
+                    ok;
+                false ->
+                    {error, 'feature-not-implemented', 'persistent-items'}
+            end;
+        false ->
+            {error, 'feature-not-implemented', 'retrieve-items'}
+    end;
+%-- Subscribe_Node --%
+features('subscribe_node', Pubsub_Features, {[] = _Subscribe_Options}) ->
+    case lists:member(<<"subscribe">>, Pubsub_Features) of
+        true ->
+            ok;
+        false ->
+            {error, 'feature-not-implemented', 'retrieve-items'}
+    end;
+%%
+features('subscribe_node', Pubsub_Features, {_Subscribe_Options}) ->
+    case lists:member(<<"subscribe">>, Pubsub_Features) of
+        true ->
+            case lists:member(<<"subscription-options">>, Pubsub_Features) of
+                true ->
+                    ok;
+                false ->
+                    {error, 'feature-not-implemented', 'subscription-options'}
+            end;
+        false ->
+            {error, 'feature-not-implemented', 'retrieve-items'}
+    end;
+%-- Get_Configure_Subscription_Default --%
+features('get_configure_subscription_default', Pubsub_Features, 'none') ->
+    case lists:member(<<"subscription-options">>, Pubsub_Features) of
+        true ->
+            case lists:member(<<"retrieve-default-sub">>, Pubsub_Features) of
+                true ->
+                    ok;
+                false ->
+                    {error, 'feature-not-implemented', 'retrieve-default-sub'}
+            end;
+        false ->
+            {error, 'feature-not-implemented', 'subscription-options'}
+    end;
+%-- Get_Configure_Node_Default --%
+features('get_configure_node_default', Pubsub_Features, 'none') ->
+    case lists:member(<<"config-node">>, Pubsub_Features) of
+        true ->
+            case lists:member(<<"retrieve-default">>, Pubsub_Features) of
+                true ->
+                    ok;
+                false ->
+                    {error, 'feature-not-implemented', 'retrieve-default'}
+            end;
+        false ->
+            {error, 'feature-not-implemented', 'config-node'}
+    end.
+
+
+%-- Create_Node --%
+-spec(create_node/5 ::
+(
+  Host         :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host  :: exmpp_pubsub:host(),
+  Entity       :: xmpp_jid:usr_entity(),
+  Parameters   :: {NodeId :: undefined | exmpp_pubsub:nodeId(),
+                   Node_Config :: [] | [Xmlel::xmlel(),...]},
+  Capabilities :: #capabilities{})
+    -> %%
+       {result, [Xmlel_Pubsub::xmlel(),...]}
+    %%%
+     | {error, 'feature-not-implemented', 'create-nodes'}
+     | {error, 'feature-not-implemented', 'create-and-configure'}
+     %
+     | {error, 'not-acceptable', 'nodeid-required'}
+     %
+     | {error, 'forbidden'}
+     | {error, 'conflict'}
+     %
+     | {error, 'not-acceptable'}
+     | {error, 'feature-not-implemented', 'collections'}
+     %
+     | {error, 'invalid-options'}
+     | {error, 'jid-malformed'}
+     %
+     | {error, 'not-acceptable'}
+     | {error, 'not-acceptable', 'unsupported-access-model'}
+     %
+     | {error, 'feature-not-implemented', 'collections'}
+     | {error, 'feature-not-implemented', 'multi-collections'}
+).
+
+
+create_node(Host, Pubsub_Host, {U,S,R} = Entity,
+  {NodeId, Node_Config} = _Parameters,
+  #capabilities{
+    plugin = Plugin,
+    api = #api{db = API_DB, broadcast = API_Broadcast, options = Options_Mod}}
+  = _Capabilities) ->
+    case
+        checks_on_create_node(Host, {U,S,R}, Plugin, {NodeId, Node_Config},
+            Options_Mod)
+    of
+        {ok, Pubsub_Features, Node_Options} ->
+            case
+                pubsub_db:transaction('mnesia',
+                    API_DB#api_db.create_node,
+                    'create_node',
+                    [Host, Pubsub_Host, {U,S,undefined}, Pubsub_Features,
+                        {NodeId, Node_Options}]
+                )
+            of
+                {result, NodeId_Bis, _Actions} ->
+                    case
+                        (_Actions =/= [])
+                             andalso
+                        lists:member(<<"subscription-notifications">>,
+                            Pubsub_Features)
+                    of
+                        true ->
+                            [{Notification_Type, Subscription}] = _Actions,
+                            spawn(API_Broadcast
+                                #api_broadcast.notify_subscriptions,
+                                'notify_subscriptions',
+                                [Host, Pubsub_Host, NodeId_Bis, Notification_Type,
+                                    [{Entity, [Subscription]}]]);
+                        false ->
+                            ok
+                    end,
+                    {result,
+                        [exmpp_pubsub:xmlel_pubsub('pubsub',
+                            [exmpp_pubsub:xmlel_create(NodeId_Bis)])]};
+                Error ->
+                    Error
+            end;
+        Error ->
+            Error
+    end.
+
+
+checks_on_create_node(Host, {U,S,R} = _Entity, Plugin, {NodeId, Node_Config},
+  Options_Mod) ->
+    case
+        features('create_node', Pubsub_Features = Plugin:pubsub_features(),
+            {NodeId, Node_Config})
+    of
+        ok ->
+            case
+                acl:match_rule(Host, pubsub_createnode,
+                    jlib:jid_to_string({U, S, <<>>}))
+            of
+                allow ->
+                    case
+                        Options_Mod:parse_xmlel_x(Plugin, Pubsub_Features,
+                            {U,S,R}, 'node_config', Node_Config)
+                    of
+                        {ok, Node_Options} ->
+                            {ok, Pubsub_Features, Node_Options};
+                        Error ->
+                            Error
+                    end;
+                _Deny ->
+                    {error, 'forbidden'}
+            end;
+        Error ->
+            Error
+    end.
+
+%-- Delete_Node --%
+-spec(delete_node/5 ::
+(
+  Host         :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host  :: exmpp_pubsub:host(),
+  Entity       :: xmpp_jid:usr_entity(),
+  Parameters   :: {NodeId :: undefined | exmpp_pubsub:nodeId(),
+                   RedirectURI :: undefined | binary()},
+  Capabilities :: #capabilities{})
+    -> {result, []}
+    %%%
+     | {error, 'feature-not-implemented', 'delete-nodes'}
+     %
+     | {error, 'item-not-found'}
+     | {error, 'forbidden'}
+).
+
+delete_node(Host, Pubsub_Host, {U,S,_R} = _Entity,
+   _Parameters = {NodeId, RedirectURI},
+   #capabilities{plugin = Plugin, api = #api{db = API_DB, broadcast = API_Broadcast}}
+   = _Capabilities) ->
+     Pubsub_Features = Plugin:pubsub_features(),
+    case lists:member(<<"delete-nodes">>, Pubsub_Features) of
+        true ->
+            case
+                pubsub_db:transaction('mnesia',
+                    API_DB#api_db.delete_node,
+                    'delete_node',
+                    [Pubsub_Host, {U,S,undefined}, {NodeId}])
+            of
+                {result, _Actions = []} ->
+                    {result, []};
+                {result,
+                 _Actions = [{Notification_Type, Recipients}]} ->
+                     spawn(API_Broadcast#api_broadcast.notify_delete,
+                         'notify_delete',
+                         [Host, Pubsub_Host, NodeId, Notification_Type,
+                          RedirectURI, Recipients]),
+                     {result, []};
+                Error ->
+                    Error
+             end;
+        false ->
+            {error, 'feature-not-implemented', 'delete-nodes'}
+     end.
+
+%-- Purge_Node --%
+-spec(purge_node/5 ::
+(
+  Host         :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host  :: exmpp_pubsub:host(),
+  Entity       :: xmpp_jid:usr_entity(),
+  Parameters   :: {NodeId :: undefined | exmpp_pubsub:nodeId()},
+  Capabilities :: #capabilities{})
+    -> {result, []}
+    %%%
+     | {error, 'feature-not-implemented', 'purge-nodes'}
+     | {error, 'feature-not-implemented', 'persistent-items'}
+     %
+     | {error, 'item-not-found'}
+     | {error, 'forbidden'}
+).
+
+purge_node(Host, Pubsub_Host, {U,S,_R} = _Entity,
+  {NodeId} = _Parameters,
+   #capabilities{plugin = Plugin, api = #api{db = API_DB, broadcast = API_Broadcast}}
+   = _Capabilities) ->
+    Pubsub_Features = Plugin:pubsub_features(),
+    case features('purge_node', Pubsub_Features, none) of
+        ok ->
+            case
+                pubsub_db:transaction('mnesia',
+                    API_DB#api_db.purge_node,
+                    'purge_node',
+                    [Pubsub_Host, {U,S,undefined}, {NodeId}])
+            of
+                {result, []} ->
+                    {result, []};
+                {result,
+                 _Actions = [{Notification_Type, Recipients}]} ->
+                     spawn(API_Broadcast#api_broadcast.notify_purge,
+                         'notify_purge',
+                         [Host, Pubsub_Host, NodeId, Notification_Type, Recipients]),
+                     {result, []};
+                 Error ->
+                     Error
+            end;
+        Error ->
+            Error
+    end.
+
+%%
+-spec(publish_item/5 ::
+(
+  Host         :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host  :: exmpp_pubsub:host(),
+  Entity       :: xmpp_jid:usr_entity(),
+  Parameters   :: {
+    NodeId          :: undefined | exmpp_pubsub:nodeId(),
+    Item            :: 0 | 1,
+    ItemId          :: undefined | exmpp_pubsub:itemId(),
+    Payload         :: exmpp_pubsub:payload() | [Xmlel::xmlel()],
+    Node_Config     :: [], %| [Xmlel::xmlel(),...],
+    Publish_Options :: [Xmlel::xmlel()]
+  },
+  Capabilities :: #capabilities{})
+    -> %%
+       {result, Xmlel_Pubsub::[Xmlel::xmlel()]}
+    %%%
+     | {error, 'forbidden'}
+     | {error, 'item-not-found'}
+    %%%
+     | {error, 'not-acceptable'}
+     | {error, 'feature-not-implemented', 'collections'}
+    %%%
+     | {error, 'invalid-options'}
+     | {error, 'jid-malformed'}
+     %
+     | {error, 'not-acceptable'}
+     | {error, 'not-acceptable', 'unsupported-access-model'}
+     %
+     | {error, 'feature-not-implemented', 'collections'}
+     | {error, 'feature-not-implemented', 'multi-collections'}
+     %
+     | {error, 'bad-request',    'invalid-payload'}
+     | {error, 'bad-request',    'item-required'}
+     | {error, 'bad-request',    'item-forbidden'}
+     | {error, 'not-acceptable', 'payload-too-big'}
+).
+publish_item(Host, Pubsub_Host, {U,S,R} = _Entity,
+  {_NodeId, Item, _ItemId, Payload, [] = Node_Config, Publish_Options},
+   #capabilities{plugin = Plugin,
+  api = #api{options = Options_Module, db = API_DB,
+  broadcast = API_Broadcast}} = _Capabilities) ->
+    case
+        checks_on_publish_item(Host, {U,S,R}, Plugin, Options_Module,
+            {_NodeId, Node_Config, Publish_Options})
+    of
+        {ok, Pubsub_Features, _Node_Options, Item_Options} ->
+            case
+                pubsub_db:transaction('mnesia',
+                    API_DB#api_db.publish_item,
+                    'publish_item',
+                    [Host, Pubsub_Host, {U,S,R}, Plugin, Pubsub_Features,
+                     {_NodeId, Item, _ItemId, Payload, {Node_Config, Item_Options}}])
+            of
+                {result, NodeId, ItemId, Node_Options, Node_Owners, SubId,
+                 Subscription, Broadcasted_Items, Pubsub_States} ->
+                    case Pubsub_States of
+                        [] ->
+                            ok;
+                        _Pubsub_States ->
+                            spawn(API_Broadcast#api_broadcast.broadcast_publish,
+                                broadcast_publish,
+                                [Host, Pubsub_Host, NodeId, Node_Options,
+                                 Node_Owners, Broadcasted_Items,
+                                 case SubId of
+                                    undefined ->
+                                        undefined;
+                                    _SubId ->
+                                        {_Subscriber = jlib:jid_to_string({U, S, <<>>}),
+                                         _Subscription_State = 'subscribed',
+                                         SubId}
+                                 end,
+                                 Pubsub_States])
+                    end,
+                    {result,
+                        [exmpp_pubsub:xmlel_pubsub('pubsub',
+                            [exmpp_pubsub:xmlel_publish('pubsub', NodeId,
+                                [exmpp_pubsub:xmlel_item('pubsub', ItemId)])]
+                        )]
+                    };
+                Error ->
+                    Error
+            end;
+        Error ->
+            Error
+    end.
+
+%%
+-spec(checks_on_publish_item/5 ::
+(
+  Host           :: xmpp_jid:raw_jid_component_bare(),
+  Entity         :: xmpp_jid:usr_entity(),
+  Plugin         :: exmpp_pubsub:plugin(),
+  Options_Module :: module(),
+  Criteria       :: {
+    NodeId          :: undefined | exmpp_pubsub:nodeId(),
+    Node_Config     :: [Xmlel_X::xmlel(),...]
+                     | [Xmlel::xmlel()],
+    Publish_Options :: [Xmlel_X::xmlel(),...]
+                     | [Xmlel::xmlel()]
+  })
+    -> {ok,
+        Pubsub_Features ::exmpp_pubsub:pubsub_features(),
+        Node_Options    :: [] | pubsub_options:options_node(),
+        Item_Options    :: [] | pubsub_options:options_item()}
+    %%%
+     | {error, 'forbidden'}
+    %%%
+     | {error, 'not-acceptable'}
+     | {error, 'feature-not-implemented', 'collections'}
+    %%%
+     | {error, 'invalid-options'}
+     | {error, 'jid-malformed'}
+     %
+     | {error, 'not-acceptable'}
+     | {error, 'not-acceptable', 'unsupported-access-model'}
+     %
+     | {error, 'feature-not-implemented', 'collections'}
+     | {error, 'feature-not-implemented', 'multi-collections'}
+).
+
+checks_on_publish_item(Host, {U,S,R} = _Entity, Plugin, Options_Module,
+  {undefined = NodeId, Node_Config, Publish_Options}) ->
+    case
+        features('publish_item', Pubsub_Features = Plugin:pubsub_features(),
+            {NodeId, Node_Config, Publish_Options})
+    of
+        ok ->
+            case
+                acl:match_rule(Host, pubsub_createnode,
+                    jlib:jid_to_string({U, S, <<>>}))
+            of
+                allow ->
+                    case
+                        {Options_Module:parse_xmlel_x(Plugin, Pubsub_Features,
+                             {U,S,R}, 'node_config', Node_Config),
+                         Options_Module:parse_xmlel_x(Plugin, Pubsub_Features,
+                             {U,S,R}, 'publish-options', Publish_Options)}
+                    of
+                        {{ok, Node_Options}, {ok, Item_Options}} ->
+                            {ok, Pubsub_Features, Node_Options, Item_Options};
+                        {Error, {ok, _Item_Options}} ->
+                            Error;
+                        {{ok, _Node_Options}, Error} ->
+                            Error;
+                        {Error, _Error} ->
+                            Error
+                    end;
+                _Deny ->
+                    {error, 'forbidden'}
+            end;
+        Error ->
+            Error
+    end;
+%%
+checks_on_publish_item(_Host, Entity, Plugin, Options_Module,
+  {NodeId, Node_Config, Publish_Options}) ->
+    case
+        features('publish_item', Pubsub_Features = Plugin:pubsub_features(),
+            {NodeId, Node_Config, Publish_Options})
+    of
+        ok ->
+            case
+                {Options_Module:parse_xmlel_x(Plugin, Pubsub_Features, Entity,
+                     'node_config', Node_Config),
+                 Options_Module:parse_xmlel_x(Plugin, Pubsub_Features, Entity,
+                     'publish-options', Publish_Options)}
+            of
+                {{ok, Node_Options}, {ok, Item_Options}} ->
+                    {ok, Pubsub_Features, Node_Options, Item_Options};
+                {Error, {ok, _Item_Options}} ->
+                    Error;
+                {{ok, _Node_Options}, Error} ->
+                    Error;
+                {Error, _Error} ->
+                    Error
+            end;
+        Error ->
+            Error
+    end.
+
+%-- Retract_Items --%
+-spec(retract_item/5 ::
+(
+  Host         :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host  :: exmpp_pubsub:host(),
+  Entity       :: xmpp_jid:usr_entity(),
+  Parameters   :: {NodeId               :: undefined | exmpp_pubsub:nodeId(),
+                   ItemId               :: undefined | exmpp_pubsub:itemId(),
+                   Adhoc_Notify_Retract :: undefined | boolean()},
+  Capabilities :: #capabilities{})
+    -> {result, []}
+    %%%
+     | {error, 'feature-not-implemented', 'delete-items'}
+     | {error, 'feature-not-implemented', 'persistent-items'}
+     %
+     | {error, 'bad-request', 'nodeid-required'}
+     | {error, 'bad-request', 'item-required'}
+     %
+     | {error, 'item-not-found'}
+     | {error, 'forbidden'}
+).
+
+retract_item(Host, Pubsub_Host, {U,S,_R} = _Entity,
+  {NodeId, ItemId, Adhoc_Notify_Retract} = _Parameters,
+   #capabilities{plugin = Plugin, api = #api{db = API_DB, broadcast = API_Broadcast}}
+   = _Capabilities) ->
+    Pubsub_Features = Plugin:pubsub_features(),
+    case features('retract_item', Pubsub_Features, none) of
+        ok ->
+            case
+                pubsub_db:transaction('mnesia',
+                    API_DB#api_db.retract_item,
+                    'retract_item',
+                    [Pubsub_Host, {U,S,undefined},
+                     {NodeId, ItemId, Adhoc_Notify_Retract}])
+            of
+                {result, []} ->
+                    {result, []};
+                {result,
+                 [_Notify_Retract = {
+                      Node_Owners, Node_Options, Item_Options, Pubsub_States
+                  }]} ->
+                    spawn(API_Broadcast#api_broadcast.broadcast_publish,
+                        broadcast_publish,
+                        [Host, Pubsub_Host, NodeId, Node_Options, Node_Owners,
+                         {[{ItemId, Item_Options}], []}, undefined, Pubsub_States]),
+                    {result, []};
+                 Error ->
+                     Error
+            end;
+        Error ->
+            Error
+    end.
+
+%-- Subscribe_Node --%
+-spec(subscribe_node/5 ::
+(
+  Host         :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host  :: exmpp_pubsub:host(),
+  Entity       :: xmpp_jid:usr_entity(),
+  Parameters   :: {NodeId            :: undefined | exmpp_pubsub:nodeId(),
+                   Jid               :: binary() | undefined,
+                   Subscribe_Options :: [Xmlel::xmlel(),...]
+                                      | [Xmlel::xmlel()]},
+  Capabilities :: #capabilities{})
+    -> {result, [Xmlel_Pubsub::xmlel(),...]}
+    %%%
+     | {error, 'feature-not-implemented', 'subscribe'}
+     | {error, 'feature-not-implemented', 'subscription-options'}
+     %
+     | {error, 'bad-request', 'invalid-jid'}
+     %
+     | {error, 'item-not-found'}
+     | {error, 'forbidden'}
+     %
+     | {error, 'invalid-options'}
+     | {error, 'not-acceptable'}
+     %
+     | {error, 'not-authorized', 'presence-subscription-required'}
+     | {error, 'not-authorized', 'not-in-roster-group'}
+     | {error, 'not-authorized', 'pending-subscription'}
+     | {error, 'not-allowed',    'closed-node'}
+).
+
+subscribe_node(Host, Pubsub_Host, {U,S,_} = Entity,
+  {NodeId, Jid, Subscribe_Options} = _Parameters,
+   #capabilities{plugin = Plugin,
+    api = #api{options = Options_Module, db = API_DB, broadcast = API_Broadcast}}
+   = _Capabilities) ->
+    Pubsub_Features = Plugin:pubsub_features(),
+    case features('subscribe_node', Pubsub_Features, {Subscribe_Options}) of
+        ok ->
+            case is_jid(Jid) of
+                #jid{luser = U, lserver = S, lresource = Resource} ->
+                    case
+                        pubsub_db:transaction('mnesia',
+                            API_DB#api_db.subscribe_node,
+                            'subscribe_node',
+                            [Host, Pubsub_Host, {U,S,undefined}, Plugin, Options_Module,
+                             Pubsub_Features,
+                             {NodeId, Resource, Subscribe_Options}])
+                    of
+                        {result,
+                         {Subscription_State, SubId, _Resource, _Subscription_Options}
+                         = Subscription, Affiliation,
+                         Node_Owners, Node_Options, Pubsub_Last_Item} ->
+                            case Pubsub_Last_Item of
+                                #pubsub_last_item_dev{
+                                    id       = ItemId,
+                                    creation = {DateTime, Creator},
+                                    payload  = Payload,
+                                    options  = Item_Options
+                                } ->
+                                    spawn(API_Broadcast#api_broadcast.broadcast_publish_last,
+                                        broadcast_publish_last,
+                                        [Host, Pubsub_Host, NodeId, Node_Options,
+                                         Node_Owners,
+                                        [{ItemId, Item_Options, Payload, Creator, DateTime}],
+                                        Entity, Affiliation, Subscription]);
+                                _ ->
+                                    ok
+                            end,
+                            {result,
+                             [exmpp_pubsub:xmlel_pubsub('pubsub',
+                                  [exmpp_pubsub:xmlel_subscription('pubsub',
+                                       NodeId, Jid, SubId, Subscription_State)])]};
+                        Error ->
+                            Error
+                    end;
+                _ ->
+                    {error, 'bad-request', 'invalid-jid'}
+            end;
+        Error ->
+            Error
+    end.
+
+%-- Unubscribe_Node --%
+-spec(unsubscribe_node/5 ::
+(
+  Host         :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host  :: exmpp_pubsub:host(),
+  Entity       :: xmpp_jid:usr_entity(),
+  Parameters   :: {NodeId :: undefined | exmpp_pubsub:nodeId(),
+                   Jid    :: binary() | undefined,
+                   _SubId :: undefined | exmpp_pubsub:subId()},
+  Capabilities :: #capabilities{})
+    -> {result, []}
+    %%%
+     | {error, 'feature-not-implemented', 'subscribe'}
+     | {error, 'forbidden'}
+     %
+     | {error, 'item-not-found'}
+     | {error, 'forbidden'}
+     | {error, 'unexpected',     'not-subscribed'}
+     %
+     | {error, 'unexpected',     'not-subscribed'}
+     | {error, 'not-acceptable', 'invalid-subid'}
+     | {error, 'bad-request',    'subid-required'}
+     | {error, 'not-acceptable', 'invalid-subid'}
+).
+
+unsubscribe_node(Host, Pubsub_Host, {U,S,_} = Entity,
+  {NodeId, Jid, _SubId} = _Parameters,
+   #capabilities{plugin = Plugin, api = #api{db = API_DB, broadcast = API_Broadcast}}
+   = _Capabilities) ->
+    case lists:member(<<"subscribe">>, Pubsub_Features = Plugin:pubsub_features()) of
+        true ->
+            case is_jid(Jid) of
+                #jid{luser = U, lserver = S, lresource = Resource} ->
+                    case
+                        pubsub_db:transaction('mnesia',
+                            API_DB#api_db.unsubscribe_node,
+                            'unsubscribe_node',
+                            [Host, Pubsub_Host, {U,S,undefined},
+                             {NodeId, Resource, _SubId}])
+                    of
+                        {result, SubId} ->
+                            {result, []};
+                        {result, SubId, Node_Owners, Notification_Type} ->
+                            spawn(API_Broadcast#api_broadcast.notify_subscription,
+                                notify_subscription,
+                                [Host, NodeId, jlib:jid_to_string({<<>>, Host, <<>>}),
+                                 Node_Owners, Notification_Type,
+                                 {Jid, 'none', SubId}]),
+                            {result, []};
+                        Error ->
+                            Error
+                    end;
+                _ ->
+                    {error, 'forbidden'}
+            end;
+        false ->
+            {error, 'feature-not-implemented', 'subscribe'}
+    end.
+
+%-- Get_Items --%
+-spec(get_items/5 ::
+(
+  Host         :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host  :: exmpp_pubsub:host(),
+  Entity       :: xmpp_jid:usr_entity(),
+  Parameters   :: {NodeId    :: undefined | exmpp_pubsub:nodeId(),
+                   _SubId    :: undefined | exmpp_pubsub:subId(),
+                   Max_Items :: non_neg_integer(),
+                   ItemIds   :: undefined}
+                | {NodeId    :: undefined | exmpp_pubsub:nodeId(),
+                   _SubId    :: undefined | exmpp_pubsub:subId(),
+                   Max_Items :: undefined,
+                   ItemIds   :: [] | exmpp_pubsub:itemIds()},
+  Capabilities :: #capabilities{})
+    -> {result, [Xmlel_Pubsub::xmlel(),...]}
+    %%%
+     | {error, 'feature-not-implemented', 'retrieve-items'}
+     | {error, 'feature-not-implemented', 'persistent-items'}
+     %
+     | {error, 'item-not-found'}
+     | {error, 'forbidden'}
+     | {error, 'not-authorized', 'presence-subscription-required'}
+     | {error, 'not-authorized', 'not-in-roster-group'}
+     | {error, 'not-allowed',    'closed-node'}
+).
+
+get_items(Host, Pubsub_Host, {U,S,_} = _Entity,
+  {NodeId, SubId, Max_Items, ItemIds},
+   #capabilities{plugin = Plugin, api = #api{db = API_DB}} = _Capabilities) ->
+    case features('get_items', Plugin:pubsub_features(), none) of
+        ok ->
+            case
+                pubsub_db:transaction('mnesia',
+                    API_DB#api_db.get_items,
+                    'get_items',
+                    [Host, Pubsub_Host, {U,S,undefined},
+                     {NodeId, SubId, Max_Items, ItemIds}])
+            of
+                {result, Pubsub_Items, Cache, Node_Owners, Node_Access_Model,
+                 Node_Groups, Affiliation, Access} ->
+                    {result,
+                     [exmpp_pubsub:xmlel_pubsub('pubsub',
+                          [exmpp_pubsub:xmlel_items('pubsub', NodeId,
+                               result_get_items(Host, Pubsub_Items,
+                                   {{U,S,undefined}, Affiliation, Access},
+                                   {Node_Owners, Node_Access_Model, Node_Groups},
+                                   Cache, []))])]};
+                Error ->
+                    Error
+            end;
+        Error ->
+            Error
+    end.
+
+%%
+-spec(result_get_items/6 ::
+(
+  Host :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Items :: [] | mod_pubsub_dev:pubsub_items(),
+  Entity_Parameters :: {Entity      :: xmpp_jid:usr_bare(),
+                        Affiliation :: 'member' | 'none' | 'owner' | 'publisher',
+                        Access      :: undefined | 'presence' | 'roster' | 'authorize'},
+  Node_Parameters   :: {Node_Owners       :: mod_pubsub_dev:node_owners(),
+                        Node_Access_Model :: pubsub_options:access_model(),
+                        Node_Groups       :: [Group::binary()]},
+  Cache             :: {Presence_Cache :: undefined | boolean(),
+                        Groups_Cache   :: undefined
+                                        | [{Entity :: xmpp_jid:usr_bare(),
+                                            Groups :: [Group::binary()]}]},
+  Xmlels_Item       :: [Xmlel_Item::#xmlel{name::binary(), children::[]}])
+    -> Xmlels_Item :: [Xmlel_Item::#xmlel{name::binary(), children::[]}]
+).
+
+result_get_items(_Host, [] = _Pubsub_Items, _Entity_Parameters, _Node_Parameters,
+  _Cache, Xmlels_Item) ->
+    Xmlels_Item;
+%%
+result_get_items(Host,
+  [#pubsub_item_dev{id = {ItemId, _NodeIdx}, payload = Payload, options = Item_Options}
+  | Pubsub_Items],
+  {Entity, Affiliation, Access},
+  {Node_Owners, Node_Access_Model, Node_Groups},
+  Cache, Xmlels_Item)
+  when   Item_Options == []
+  orelse Affiliation  == 'owner' ->
+    result_get_items(Host, Pubsub_Items,
+        {Entity, Affiliation, Access},
+        {Node_Owners, Node_Access_Model, Node_Groups},
+        Cache,
+        [exmpp_pubsub:xmlel_item('pubsub', ItemId, Payload)
+        | Xmlels_Item]);
+%%
+result_get_items(Host,
+  [#pubsub_item_dev{id = {ItemId, _NodeIdx}, payload = Payload, options = Item_Options} | Pubsub_Items],
+  {Entity, Affiliation, Access},
+  {Node_Owners, Node_Access_Model, Node_Groups},
+  {Presence_Cache, Groups_Cache} = _Cache, Xmlels_Item) ->
+    Item_Groups = get_value(Item_Options, 'roster_groups_allowed', []),
+    case get_value(Item_Options, 'access_model', undefined) of
+        %%
+        Item_Access_Model
+          when   Item_Access_Model == undefined
+          orelse Item_Access_Model == 'open'
+          orelse Item_Access_Model == 'authorize'
+          orelse Item_Access_Model == 'whitelist'
+          %
+          orelse (Item_Access_Model == Node_Access_Model
+              andalso
+                  Item_Access_Model =/= 'roster')
+          %
+          orelse (Item_Access_Model == 'presence'
+              andalso
+                  (Access == 'presence'
+                       orelse
+                   Access == 'roster'
+                       orelse
+                   Presence_Cache == true))
+          %
+          orelse (Item_Access_Model == 'roster'
+              andalso
+                  Node_Access_Model == 'roster'
+              andalso
+                  Item_Groups == [])
+          %
+          orelse ((Item_Access_Model == 'authorize'
+                       orelse
+                   Item_Access_Model == 'whitelist')
+              andalso
+                  (Affiliation == 'member'
+                       orelse
+                   Affiliation == 'publisher')) ->
+            result_get_items(Host, Pubsub_Items,
+                {Entity, Affiliation, Access},
+                {Node_Owners, Node_Access_Model, Node_Groups},
+                {Presence_Cache, Groups_Cache},
+                [exmpp_pubsub:xmlel_item('pubsub', ItemId, Payload)
+                | Xmlels_Item]);
+        %%
+        Item_Access_Model
+          when    Item_Access_Model == 'presence'
+          andalso Presence_Cache    == undefined ->
+            case is_contact_subscribed_to_node_owners(Host, Entity, Node_Owners) of
+                false ->
+                    result_get_items(Host, Pubsub_Items,
+                        {Entity, Affiliation, Access},
+                        {Node_Owners, Node_Access_Model, Node_Groups},
+                        {_Presence_Cache = false, Groups_Cache},
+                        Xmlels_Item);
+                _Node_Owner ->
+                    result_get_items(Host, Pubsub_Items,
+                        {Entity, Affiliation, Access},
+                        {Node_Owners, Node_Access_Model, Node_Groups},
+                        {_Presence_Cache = true, Groups_Cache},
+                        [exmpp_pubsub:xmlel_item('pubsub', ItemId, Payload)
+                        | Xmlels_Item])
+            end;
+        Item_Access_Model
+          when    Item_Access_Model == 'roster'
+          andalso Groups_Cache      == undefined ->
+            case is_contact_in_allowed_roster_groups(Entity, Item_Groups) of
+                {Node_Owner, Roster_Group} ->
+                    result_get_items(Host, Pubsub_Items,
+                        {Entity, Affiliation, Access},
+                        {Node_Owners, Node_Access_Model, Node_Groups},
+                        {Presence_Cache, _Groups_Cache = [{Node_Owner, [Roster_Group]}]},
+                        [exmpp_pubsub:xmlel_item('pubsub', ItemId, Payload)
+                        | Xmlels_Item]);
+                false ->
+                    result_get_items(Host, Pubsub_Items,
+                        {Entity, Affiliation, Access},
+                        {Node_Owners, Node_Access_Model, Node_Groups},
+                        {Presence_Cache, Groups_Cache},
+                        Xmlels_Item)
+            end;
+        Item_Access_Model
+          when Item_Access_Model == 'roster' ->
+            case
+                lists:any(fun
+                    ({Owner, Groups}) ->
+                        case lists:keyfind(Owner, 1, Item_Groups) of
+                            {_Owner, Owner_Groups} ->
+                                lists:any(fun
+                                    (Group) ->
+                                        lists:member(Group, Owner_Groups)
+                                end, Groups);
+                            false ->
+                                false
+                        end
+                end, Groups_Cache)
+            of
+                true ->
+                    result_get_items(Host, Pubsub_Items,
+                        {Entity, Affiliation, Access},
+                        {Node_Owners, Node_Access_Model, Node_Groups},
+                        {Presence_Cache, Groups_Cache},
+                        [exmpp_pubsub:xmlel_item('pubsub', ItemId, Payload)
+                        | Xmlels_Item]);
+                false ->
+                    case is_contact_in_allowed_roster_groups(Entity, Node_Groups) of
+                        {Node_Owner, Roster_Group} ->
+                            result_get_items(Host, Pubsub_Items,
+                                {Entity, Affiliation, Access},
+                                {Node_Owners, Node_Access_Model, Node_Groups},
+                                {Presence_Cache,
+                                 _Groups_Cache = case
+                                     lists:keyfind(Node_Owner, 1, Groups_Cache)
+                                of
+                                    {_Node_Owner, Node_Owner_Groups} ->
+                                        lists:keyreplace(Node_Owner, 1, Groups_Cache,
+                                            {Node_Owner,
+                                             [Roster_Group
+                                             | lists:delete(Roster_Group,  Node_Owner_Groups)]});
+                                    false ->
+                                        [{Node_Owner, [Roster_Group]} | Groups_Cache]
+                                end},
+                                [exmpp_pubsub:xmlel_item('pubsub', ItemId, Payload)
+                                | Xmlels_Item]);
+                        false ->
+                            result_get_items(Host, Pubsub_Items,
+                                {Entity, Affiliation, Access},
+                                {Node_Owners, Node_Access_Model, Node_Groups},
+                                {Presence_Cache, Groups_Cache},
+                                Xmlels_Item)
+                    end
+            end;
+        _ ->
+            result_get_items(Host, Pubsub_Items,
+                {Entity, Affiliation, Access},
+                {Node_Owners, Node_Access_Model, Node_Groups},
+                {Presence_Cache, Groups_Cache},
+                Xmlels_Item)
+    end.
+
+%-- Set_Configure_Subscription --%
+-spec(set_configure_subscription/5 ::
+(
+  Host         :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host  :: exmpp_pubsub:host(),
+  Entity       :: xmpp_jid:usr_entity(),
+  Parameters   :: {NodeId            :: undefined | exmpp_pubsub:nodeId(),
+                   Jid               :: binary() | undefined,
+                   SubId             :: undefined | exmpp_pubsub:subId(),
+                   Subscribe_Options :: [Xmlel::xmlel(),...]
+                                      | [Xmlel::xmlel()]},
+  Capabilities :: #capabilities{})
+    -> {result, []}
+    %%%
+     | {error, 'feature-not-implemented', 'subscription-options'}
+     %
+     | {error, 'bad-request', 'invalid-options'}
+     | {error, 'bad-request', 'jid-required'}
+     | {error, 'bad-request', 'invalid-jid'}
+     %
+     | {error, 'item-not-found'}
+     | {error, 'unexpected-request', 'not-subscribed'}
+     | {error, 'forbidden'}
+     | {error, 'bad-request', 'invalid-options'}
+     %
+     | {error, 'unexpected-request', 'not-subscribed'}
+     | {error, 'bad-request',        'subid-required'}
+     | {error, 'forbidden'}
+     | {error, 'not-acceptable',     'invalid-subid'}
+).
+
+set_configure_subscription(Host, Pubsub_Host, {U,S,_} = Entity,
+  {NodeId, Jid, SubId, Subscribe_Options},
+   #capabilities{plugin = Plugin, api = #api{options = Options_Module, db = API_DB}}
+   = _Capabilities) ->
+    case
+        checks_on_set_configure_subscription(Entity, Jid, Plugin,
+            Subscribe_Options)
+    of
+        {ok, Pubsub_Features, Resource} ->
+            case
+                pubsub_db:transaction('mnesia',
+                    API_DB#api_db.set_configure_subscription,
+                    'set_configure_subscription',
+                    [Host, Pubsub_Host, Entity, Plugin, Options_Module,
+                    Pubsub_Features, {NodeId, SubId, Resource, Subscribe_Options}])
+            of
+                {result, []} ->
+                    {result, []};
+                Error ->
+                    Error
+            end;
+        Error ->
+            Error
+    end.
+
+%%
+-spec(checks_on_set_configure_subscription/4 ::
+(
+  Entity            :: xmpp_jid:usr_entity(),
+  Subscriber_Jid    :: binary() | undefined,
+  Plugin            :: exmpp_pubsub:plugin(),
+  Subscribe_Options :: [Xmlel::xmlel(),...]
+                     | [Xmlel::xmlel()])
+    -> {ok,
+        Pubsub_Features :: exmpp_pubsub:pubsub_features(),
+        Resource        :: undefined | xmpp_jid:resource_jid()}
+    %%%
+     | {error, 'feature-not-implemented', 'subscription-options'}
+     %
+     | {error, 'bad-request', 'invalid-options'}
+     | {error, 'bad-request', 'jid-required'}
+     | {error, 'bad-request', 'invalid-jid'}
+).
+
+checks_on_set_configure_subscription({U,S,_} = _Entity, Subscriber_Jid, Plugin,
+  Subscribe_Options) ->
+    Pubsub_Features = Plugin:pubsub_features(),
+    case lists:member(<<"subscription-options">>, Pubsub_Features) of
+        true ->
+            case Subscribe_Options of
+                [] ->
+                    {error, 'bad-request', 'invalid-options'};
+                _ ->
+                    case Subscriber_Jid of
+                        undefined ->
+                            {error, 'bad-request', 'jid-required'};
+                        _ ->
+                            case is_jid(Subscriber_Jid) of
+                                #jid{luser = U, lserver = S, lresource = Resource} ->
+                                    {ok, Pubsub_Features, Resource};
+                                _ ->
+                                    {error, 'bad-request', 'invalid-jid'}
+                            end
+                    end
+            end;
+        false ->
+            {error, 'feature-not-implemented', 'subscription-options'}
+    end.
+
+%-- Get_Entity_Affiliations --%
+-spec(get_entity_affiliations/5 ::
+(
+  Host         :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host  :: exmpp_pubsub:host(),
+  Entity       :: xmpp_jid:usr_entity(),
+  Parameters   :: {NodeId :: undefined | exmpp_pubsub:nodeId()},
+  Capabilities :: #capabilities{})
+    -> {result, [Xmlel_Pubsub::xmlel(),...]}
+    %%%
+     | {error, 'feature-not-implemented', 'retrieve-affiliations'}
+).
+
+get_entity_affiliations(_Host, Pubsub_Host, {U,S,_R} = _Entity,
+  {NodeId} = _Parameters,
+   #capabilities{plugin = Plugin, api = #api{db = API_DB}} = _Capabilities) ->
+    case
+        lists:member(<<"retrieve-affiliations">>,
+            _Pubsub_Features = Plugin:pubsub_features())
+    of
+        true ->
+            {result,
+             result_get_entity_affiliations(
+                 _Entity_Affiliations = pubsub_db:transaction('mnesia',
+                     API_DB#api_db.get_entity_affiliations,
+                     'get_entity_affiliations',
+                     [Pubsub_Host, {U,S,undefined}, {NodeId}]))};
+        false ->
+            {error, 'feature-not-implemented', 'retrieve-affiliations'}
+    end.
+
+%%
+-spec(result_get_entity_affiliations/1 ::
+(
+  Entity_Affiliations :: [Entity_Affiliation :: {
+                              NodeId :: exmpp_pubsub:nodeId(),
+                              Affiliation :: exmpp_pubsub:affiliation()
+                          }])
+    -> [Xmlel_Pubsub::xmlel(),...]
+).
+
+result_get_entity_affiliations(Entity_Affiliations) ->
+    [exmpp_pubsub:xmlel_pubsub('pubsub',
+         [exmpp_pubsub:xmlel_affiliations('pubsub',
+              lists:map(fun({NodeId, Affiliation}) ->
+                  exmpp_pubsub:xmlel_affiliation('pubsub', NodeId, Affiliation)
+              end, Entity_Affiliations)
+         )]
+    )].
+
+
+%-- Get_Entity_Subscriptions --%
+-spec(get_entity_subscriptions/5 ::
+(
+  Host         :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host  :: exmpp_pubsub:host(),
+  Entity       :: xmpp_jid:usr_entity(),
+  Parameters   :: {NodeId :: undefined | exmpp_pubsub:nodeId()},
+  Capabilities :: #capabilities{})
+    -> {result, [Xmlel_Pubsub::xmlel(),...]}
+    %%%
+     | {error, 'feature-not-implemented', 'retrieve-subscriptions'}
+).
+
+get_entity_subscriptions(_Host, Pubsub_Host, {U,S,_R} = _Entity,
+  {NodeId} = _Parameters,
+   #capabilities{plugin = Plugin, api = #api{db = API_DB}} = _Capabilities) ->
+    case
+        lists:member(<<"retrieve-subscriptions">>,
+            _Pubsub_Features = Plugin:pubsub_features())
+    of
+        true ->
+            {result,
+             result_get_entity_subscriptions({U,S,undefined},
+                 _Entity_Subscriptions = pubsub_db:transaction('mnesia',
+                     API_DB#api_db.get_entity_subscriptions,
+                     'get_entity_subscriptions',
+                     [Pubsub_Host, {U,S,undefined}, {NodeId}]))
+            };
+        false ->
+            {error, 'feature-not-implemented', 'retrieve-subscriptions'}
+    end.
+
+%%
+-spec(result_get_entity_subscriptions/2 ::
+(
+  Entity               :: xmpp_jid:usr_bare(),
+  Entity_Subscriptions :: [{NodeId::exmpp_pubsub:nodeId(),
+                            Subscriptions::exmpp_pubsub:subscriptions()}])
+    -> [Xmlel_Pubsub::xmlel(),...]
+).
+
+result_get_entity_subscriptions({U,S,_R} = _Entity, Entity_Subscriptions) ->
+    [exmpp_pubsub:xmlel_pubsub('pubsub',
+         [exmpp_pubsub:xmlel_subscriptions('pubsub',
+              lists:map(fun
+                  ({NodeId, Subscriptions}) ->
+                      lists:map(fun
+                          %%
+                          ({Subscription_State, SubId, {caps, Resource},
+                            _Subscription_Options}) ->
+                              exmpp_pubsub:xmlel_subscription('pubsub',
+                                  NodeId,
+                                  _Jid = jlib:jid_to_string({U, S, <<>>}),
+                                  SubId,
+                                  Subscription_State);
+                          %%
+                          ({Subscription_State, SubId, Resource,
+                            _Subscription_Options}) ->
+                              exmpp_pubsub:xmlel_subscription('pubsub',
+                                  NodeId,
+                                  _Jid = jlib:jid_to_string({U, S, Resource}),
+                                  SubId,
+                                  Subscription_State)
+                          %
+                      end, Subscriptions)
+              end, Entity_Subscriptions)
+         )]
+    )].
+
+
+%-- Get_Node_Affiliations --%
+-spec(get_node_affiliations/5 ::
+(
+  Host         :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host  :: exmpp_pubsub:host(),
+  Entity       :: xmpp_jid:usr_entity(),
+  Parameters   :: {NodeId :: undefined | exmpp_pubsub:nodeId()},
+  Capabilities :: #capabilities{})
+    -> {result, [Xmlel_Pubsub::xmlel(),...]}
+    %%%
+     | {error, 'feature-not-implemented', 'modify-affiliations'}
+     %
+     | {error, 'item-not-found'}
+     | {error, 'forbidden'}
+).
+
+get_node_affiliations(Host, Pubsub_Host, {U,S,_R} = _Entity,
+  {NodeId} = _Parameters,
+   #capabilities{plugin = Plugin, api = #api{db = API_DB}} = _Capabilities) ->
+    case
+        lists:member(<<"modify-affiliations">>,
+            _Pubsub_Features = Plugin:pubsub_features())
+    of
+        true ->
+            case
+                pubsub_db:transaction('mnesia',
+                    API_DB#api_db.get_node_affiliations,
+                    'get_node_affiliations',
+                    [Host, Pubsub_Host, {U,S,undefined}, {NodeId}])
+            of
+                {result, Pubsub_States} ->
+                    {result, result_get_node_affiliations(NodeId, Pubsub_States)};
+                Error ->
+                    Error
+            end;
+        false ->
+            {error, 'feature-not-implemented', 'modify-affiliations'}
+    end.
+
+%%
+-spec(result_get_node_affiliations/2 ::
+(
+  NodeId        :: exmpp_pubsub:nodeId(),
+  Pubsub_States :: [Pusbub_State::#pubsub_state_dev{},...])
+    -> [Xmlel_Pubsub::xmlel(),...]
+).
+
+result_get_node_affiliations(NodeId, Pubsub_States) ->
+    [exmpp_pubsub:xmlel_pubsub('pubsub#owner',
+         [exmpp_pubsub:xmlel_affiliations('pubsub#owner', NodeId,
+              lists:map(fun
+                  (#pubsub_state_dev{id = {Entity, _NodeIdx},
+                   affiliation = Affiliation}) ->
+                      exmpp_pubsub:xmlel_affiliation('pubsub#owner',
+                          _Jid = pubsub_tools:jid_to_string(Entity),
+                          Affiliation)
+              end, Pubsub_States)
+         )]
+    )].
+
+
+%-- Get_Node_Subscriptions --%
+-spec(get_node_subscriptions/5 ::
+(
+  Host         :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host  :: exmpp_pubsub:host(),
+  Entity       :: xmpp_jid:usr_entity(),
+  Parameters   :: {NodeId :: undefined | exmpp_pubsub:nodeId()},
+  Capabilities :: #capabilities{})
+    -> {result, [Xmlel_Pubsub::xmlel(),...]}
+    %%%
+     | {error, 'feature-not-implemented', 'manage-subscriptions'}
+     %
+     | {error, 'item-not-found'}
+     | {error, 'forbidden'}
+).
+
+get_node_subscriptions(Host, Pubsub_Host, {U,S,_R} = _Entity,
+  {NodeId} = _Parameters,
+   #capabilities{plugin = Plugin, api = #api{db = API_DB}} = _Capabilities) ->
+    case
+        lists:member(<<"manage-subscriptions">>,
+            _Pubsub_Features = Plugin:pubsub_features())
+    of
+        true ->
+            case
+                 pubsub_db:transaction('mnesia',
+                    API_DB#api_db.get_node_subscriptions,
+                    'get_node_subscriptions',
+                    [Host, Pubsub_Host, {U,S,undefined}, {NodeId}])
+            of
+                {result, Pubsub_States} ->
+                    {result, result_get_node_subscriptions(NodeId, Pubsub_States)};
+                Error ->
+                    Error
+            end;
+        false ->
+            {error, 'feature-not-implemented', 'manage-subscriptions'}
+    end.
+
+%%
+-spec(result_get_node_subscriptions/2 ::
+(
+  NodeId        :: exmpp_pubsub:nodeId(),
+  Pubsub_States :: [Pubsub_State::#pubsub_state_dev{}])
+    -> [Xmlel_Pubsub::xmlel(),...]
+).
+
+result_get_node_subscriptions(NodeId, Pubsub_States) ->
+    [exmpp_pubsub:xmlel_pubsub('pubsub#owner',
+         [exmpp_pubsub:xmlel_subscriptions('pubsub#owner', NodeId,
+              lists:foldl(fun
+                  %%
+                  (#pubsub_state_dev{affiliation = 'none'}, Xmlels_Subscription) ->
+                      Xmlels_Subscription;
+                  %%
+                      (#pubsub_state_dev{id = {{U, S, _}, _NodeIdx},
+                       subscriptions = Subscriptions}, Xmlels_Subscription) ->
+                          Xmlels_Subscription
+                          ++
+                          lists:map(fun
+                              %%
+                              ({Subscription_State, SubId, {caps, Resource},
+                                _Subscription_Options}) ->
+                                  exmpp_pubsub:xmlel_subscription('pubsub#owner',
+                                      _Jid = pubsub_tools:jid_to_string({U, S, Resource}),
+                                      SubId,
+                                      Subscription_State);
+                              %%
+                              ({Subscription_State, SubId, Resource,
+                                _Subscription_Options}) ->
+                                  exmpp_pubsub:xmlel_subscription('pubsub#owner',
+                                      _Jid = pubsub_tools:jid_to_string({U, S, Resource}),
+                                      SubId,
+                                      Subscription_State)
+                          end, Subscriptions)
+                  %
+              end, [], Pubsub_States)
+         )]
+    )].
+
+%% Get_Configure_Subscription_Default
+-spec(get_configure_subscription_default/5 ::
+(
+  Host         :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host  :: exmpp_pubsub:host(),
+  Entity       :: xmpp_jid:usr_entity(),
+  Parameters   :: {NodeId :: undefined | exmpp_pubsub:nodeId()},
+  Capabilities :: #capabilities{})
+    -> {result, [Xmlel_Pubsub::xmlel(),...]}
+    %%%
+     | {error, 'feature-not-implemented', 'subscription-options'}
+     | {error, 'feature-not-implemented', 'retrieve-default-sub'}
+     %
+     | {error, 'item-not-found'}
+     | {error, 'forbidden'}
+).
+
+get_configure_subscription_default(Host, Pubsub_Host, {U,S,_R} = _Entity,
+  {undefined = _NodeId} = _Parameters,
+   #capabilities{plugin = Plugin, api = #api{options = Options_Module,
+   db = API_DB}} = _Capabilities) ->
+    Pubsub_Features = Plugin:pubsub_features(),
+    case features('get_configure_subscription_default', Pubsub_Features, none) of
+        ok ->
+            {result,
+             [exmpp_pubsub:xmlel_pubsub('pubsub',
+                [exmpp_pubsub:xmlel_default('pubsub',
+                     [Options_Module:xdata_x('subscribe_options', 'result',
+                      Pubsub_Features, Host, {U,S,undefined},
+                      _Subscription_Options = Plugin:default_subscription_options(
+                          case Host of
+                              S -> 'local';
+                              _ -> 'remote'
+                          end,
+                         'leaf')
+                      )]
+                 )]
+              )]
+            };
+        Error ->
+            Error
+    end;
+%%
+get_configure_subscription_default(Host, Pubsub_Host, {U,S,_R} = _Entity,
+  {NodeId} = _Parameters,
+   #capabilities{plugin = Plugin, api = #api{options = Options_Module,
+   db = API_DB}} = _Capabilities) ->
+    Pubsub_Features = Plugin:pubsub_features(),
+    case features('get_configure_subscription_default', Pubsub_Features, none) of
+        ok ->
+            case
+                 pubsub_db:transaction('mnesia',
+                    API_DB#api_db.get_configure_subscription_default,
+                    'get_configure_subscription_default',
+                    [Host, Pubsub_Host, {U,S,undefined}, NodeId])
+            of
+                ok ->
+                    {result,
+                     [exmpp_pubsub:xmlel_pubsub('pubsub',
+                        [exmpp_pubsub:xmlel_default('pubsub', NodeId,
+                             [Options_Module:xdata_x('subscribe_options', 'result',
+                              Pubsub_Features, Host, {U,S,undefined},
+                              _Subscription_Options = Plugin:default_subscription_options(
+                                  case Host of
+                                      S -> 'local';
+                                      _ -> 'remote'
+                                  end,
+                                 'leaf')
+                              )]
+                         )]
+                      )]
+                    };
+                Error ->
+                    Error
+            end;
+        Error ->
+            Error
+    end.
+
+%% Get_Configure_Subscription
+-spec(get_configure_subscription/5 ::
+(
+  Host         :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host  :: exmpp_pubsub:host(),
+  Entity       :: xmpp_jid:usr_entity(),
+  Parameters   :: {NodeId :: undefined | exmpp_pubsub:nodeId(),
+                   Jid    :: binary() | undefined,
+                   SubId  :: undefined | exmpp_pubsub:subId()},
+  Capabilities :: #capabilities{})
+    -> {result, [Xmlel_Pubsub::xmlel(),...]}
+    %%%
+     | {error, 'feature-not-implemented', 'subscription-options'}
+     %
+     | {error, 'item-not-found'}
+     | {error, 'unexpected-request', 'not-subscribed'}
+     | {error, 'forbidden'}
+     %
+     | {error, 'unexpected-request', 'not-subscribed'}
+     | {error, 'bad-request',        'subid-required'}
+     | {error, 'forbidden'}
+     | {error, 'not-acceptable',     'invalid-subid'}
+).
+
+get_configure_subscription(Host, Pubsub_Host, {U,S,_R} = _Entity,
+  {NodeId, Jid, SubId} = _Parameters,
+   #capabilities{plugin = Plugin, api = #api{options = Options_Module,
+   db = API_DB}} = _Capabilities) ->
+    Pubsub_Features = Plugin:pubsub_features(),
+    case checks_on_get_configure_subscription({U,S,undefined}, Jid, Plugin) of
+        {ok, Pubsub_Features, Resource} ->
+            case
+                pubsub_db:transaction('mnesia',
+                    API_DB#api_db.get_configure_subscription,
+                    'get_configure_subscription',
+                    [Host, Pubsub_Host, {U,S,undefined}, Plugin,
+                     Pubsub_Features, {NodeId, SubId, Resource}])
+            of
+                {result, {_, _, _, Subscription_Options} = Subscription} ->
+                    {result,
+                     [exmpp_pubsub:xmlel_pubsub('pubsub',
+                        [exmpp_pubsub:xmlel_options('pubsub', NodeId, Jid, SubId,
+                             [Options_Module:xdata_x('subscribe_options', 'form',
+                              Pubsub_Features, Host, {U,S,undefined},Subscription_Options,
+                              _Default_Subscription_Options = Plugin:default_subscription_options(
+                                  case Host of
+                                      S -> 'local';
+                                      _ -> 'remote'
+                                  end,
+                                 'leaf')
+                              )]
+                         )]
+                      )]
+                    };
+                Error ->
+                    Error
+            end;
+        Error ->
+            Error
+    end.
+
+%%
+-spec(checks_on_get_configure_subscription/3 ::
+(
+  Entity            :: xmpp_jid:usr_entity(),
+  Subscriber_Jid    :: binary() | undefined,
+  Plugin            :: exmpp_pubsub:plugin())
+    -> {ok,
+        Pubsub_Features :: exmpp_pubsub:pubsub_features(),
+        Resource        :: undefined | xmpp_jid:resource_jid()}
+    %%%
+     | {error, 'feature-not-implemented', 'subscription-options'}
+     %
+     | {error, 'bad-request', 'jid-required'}
+     | {error, 'bad-request', 'invalid-jid'}
+).
+
+checks_on_get_configure_subscription({U,S,_} = _Entity, Subscriber_Jid, Plugin) ->
+    Pubsub_Features = Plugin:pubsub_features(),
+    case lists:member(<<"subscription-options">>, Pubsub_Features) of
+        true ->
+            case Subscriber_Jid of
+                undefined ->
+                    {error, 'bad-request', 'jid-required'};
+                _ ->
+                    case is_jid(Subscriber_Jid) of
+                        #jid{luser = U, lserver = S, lresource = Resource} ->
+                            {ok, Pubsub_Features, Resource};
+                        _ ->
+                            {error, 'bad-request', 'invalid-jid'}
+                    end
+            end;
+        false ->
+            {error, 'feature-not-implemented', 'subscription-options'}
+    end.
+
+%% Get_Configure_Node_Default
+-spec(get_configure_node_default/5 ::
+(
+  Host         :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host  :: exmpp_pubsub:host(),
+  Entity       :: xmpp_jid:usr_entity(),
+  Parameters   :: {NodeId :: undefined | exmpp_pubsub:nodeId()},
+  Capabilities :: #capabilities{})
+    -> {result, [Xmlel_Pubsub::xmlel(),...]}
+    %%%
+     | {error, 'feature-not-implemented', 'config-node'}
+     | {error, 'feature-not-implemented', 'retrieve-default'}
+).
+
+get_configure_node_default(Host, Pubsub_Host, {U,S,_R} = _Entity,
+  {undefined = _NodeId} = _Parameters,
+   #capabilities{plugin = Plugin, api = #api{options = Options_Module,
+   db = API_DB}} = _Capabilities) ->
+    Pubsub_Features = Plugin:pubsub_features(),
+    case features('get_configure_node_default', Pubsub_Features, none) of
+        ok ->
+            {result,
+             [exmpp_pubsub:xmlel_pubsub('pubsub#owner',
+                [exmpp_pubsub:xmlel_default('pubsub#owner',
+                     [Options_Module:xdata_x('node_config', 'form',
+                      Pubsub_Features, Host, {U,S,undefined},
+                      _Node_Options = Plugin:node_options('leaf')
+                      )]
+                 )]
+              )]
+            };
+        Error ->
+            Error
+    end.
+
+%% Get_Configure_Node
+-spec(get_configure_node/5 ::
+(
+  Host         :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host  :: exmpp_pubsub:host(),
+  Entity       :: xmpp_jid:usr_entity(),
+  Parameters   :: {NodeId :: undefined | exmpp_pubsub:nodeId()},
+  Capabilities :: #capabilities{})
+    -> {result, [Xmlel_Pubsub::xmlel(),...]}
+    %%%
+     | {error, 'feature-not-implemented', 'config-node'}
+     %
+     | {error, 'bad-request', 'nodeid-required'}
+     | {error, 'item-not-found'}
+     | {error, 'forbidden'}
+
+).
+
+get_configure_node(Host, Pubsub_Host, {U,S,_R} = _Entity,
+  {NodeId} = _Parameters,
+   #capabilities{plugin = Plugin, api = #api{options = Options_Module,
+   db = API_DB}} = _Capabilities) ->
+    Pubsub_Features = Plugin:pubsub_features(),
+    case lists:member(<<"config-node">>, Pubsub_Features) of
+        true ->
+            case
+                pubsub_db:transaction('mnesia',
+                    API_DB#api_db.get_configure_node,
+                    'get_configure_node',
+                    [Host, Pubsub_Host, {U,S,undefined}, {NodeId}])
+            of
+                {result, Node_Options} ->
+                    {result,
+                     [exmpp_pubsub:xmlel_pubsub('pubsub#owner',
+                        [exmpp_pubsub:xmlel_configure('pubsub#owner', NodeId,
+                             [Options_Module:xdata_x('node_config', 'form',
+                              Pubsub_Features, Host, {U,S,undefined}, Node_Options
+                              )]
+                         )]
+                      )]
+                    };
+                Error ->
+                    Error
+            end;
+        false ->
+            {error, 'feature-not-implemented', 'config-node'}
+    end.
+
diff --git a/src/mod_pubsub_ng/pubsub_db.erl b/src/mod_pubsub_ng/pubsub_db.erl
new file mode 100644
index 000000000..b08fe611b
--- /dev/null
+++ b/src/mod_pubsub_ng/pubsub_db.erl
@@ -0,0 +1,1575 @@
+%%% ====================================================================
+%%% ``The contents of this file are subject to the Erlang Public License,
+%%% Version 1.1, (the "License"); you may not use this file except in
+%%% compliance with the License. You should have received a copy of the
+%%% Erlang Public License along with this software. If not, it can be
+%%% retrieved via the world wide web at http:%%www.erlang.org/.
+%%% 
+%%% Software distributed under the License is distributed on an "AS IS"
+%%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%%% the License for the specific language governing rights and limitations
+%%% under the License.
+%%% 
+%%% The Initial Developer of the Original Code is ProcessOne.
+%%% Portions created by ProcessOne are Copyright 2006-2011, ProcessOne
+%%% All Rights Reserved.''
+%%% This software is copyright 2006-2011, ProcessOne.
+%%%
+%%% @copyright 2006-2011 ProcessOne
+%%% @author Karim Gemayel <karim.gemayel@process-one.net>
+%%%   [http:%%www.process-one.net/]
+%%% @version {@vsn}, {@date} {@time}
+%%% @end
+%%% ====================================================================
+
+%%% @headerfile "pubsub_dev.hrl"
+
+-module(pubsub_db).
+-author('karim.gemayel@process-one.net').
+
+-compile(export_all).
+
+-include("pubsub_dev.hrl").
+-include("pubsub_api.hrl").
+
+
+-import(pubsub_tools,
+[
+  get_option/2,
+  get_option/3,
+  get_value/2,
+  get_value/3,
+  set_value/3,
+  %%
+  check_access_model/3,
+  check_access_model/7,
+  check_publish_model/3,
+  is_contact_subscribed_to_node_owners/3,
+  is_contact_in_allowed_roster_groups/2,
+  has_subscriptions/1
+]).
+
+
+
+%% @doc Intialize mnesia
+
+-spec(init/2 ::
+(
+  Backend :: 'mnesia' | 'odbc',
+  Suffix  :: atom())
+    -> 'ok'
+).
+
+init('mnesia', Suffix) ->
+    pubsub_db_mnesia:init(Suffix);
+init('odbc', _Suffix) ->
+    ok.
+
+
+transaction('mnesia', Module, Function, Arguments) ->
+    pubsub_db_mnesia:transaction(Module, Function, Arguments).
+
+
+%%
+db_transaction(Module, Function, Arguments) ->
+    case mnesia:transaction(
+        fun() ->
+            apply(Module, Function, Arguments)
+        end)
+    of
+        {atomic, Result} ->
+            Result;
+        {aborted, Reason} ->
+            ?INFO_MSG("DB TRANSACTION ERROR ~p", [Reason]),
+            {error, 'internal-server-error'}
+    end.
+
+%-- Create_Node --%
+-spec(create_node/5 ::
+(
+  Host            :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host     :: exmpp_pubsub:host_pubsub(),
+  Entity          :: xmpp_jid:usr_bare(),
+  Pubsub_Features :: exmpp_pubsub:pubsub_features(),
+  Parameters      :: {NodeId       :: undefined | exmpp_pubsub:nodeId(),
+                      Node_Options :: pubsub_options:options_node()})
+    -> %%
+       {result,
+        NodeId :: exmpp_pubsub:nodeId(),
+        Notify :: []
+                | [Notify_Subscription :: {
+                       Notification_Type :: pubsub_options:notification_type(),
+                       Subscription      :: exmpp_pubsub:subscription_subscribed()
+                   },...]
+       }
+     %
+    %%%
+     | {error, 'conflict'}
+).
+
+create_node(Host, Pubsub_Host, {_U,S,_R} = Entity, Pubsub_Features,
+  _Parameters = {undefined = _NodeId, Node_Options}) ->
+    case
+        pubsub_db_mnesia:read_node('dev',
+            Pubsub_Host, NodeId = exmpp_pubsub:nodeId())
+    of
+        undefined ->
+            {result,
+             NodeId,
+             _Notify = case
+                 pubsub_db_mnesia:create_node('dev', Pubsub_Host, Entity, NodeId,
+                     _Level = 1, Node_Options, Pubsub_Features)
+             of
+                 undefined ->
+                     [];
+                 Subscription ->
+                     [_Notify_Subscription = {
+                          _Notification_Type = get_value(Node_Options,
+                              'notification_type', 'headline'),
+                          Subscription
+                     }]
+             end};
+        _Pubsub_Node ->
+            create_node(Host, Pubsub_Host, Entity, Pubsub_Features,
+                {_NodeId = undefined, Node_Options})
+    end;
+%%
+create_node(Host, Pubsub_Host, {_U,S,_R} = Entity, Pubsub_Features,
+  _Parameters = {NodeId, Node_Options}) ->
+    case pubsub_db_mnesia:read_node('dev', Pubsub_Host, NodeId) of
+        undefined ->
+            {result,
+             NodeId,
+             _Notify = case
+                 pubsub_db_mnesia:create_node('dev', Pubsub_Host, Entity, NodeId,
+                     _Level = 1, Node_Options, Pubsub_Features)
+             of
+                 undefined ->
+                     [];
+                 Subscription ->
+                     [_Notify_Subscription = {
+                          _Notification_Type = get_value(Node_Options,
+                              'notification_type', 'headline'),
+                          Subscription
+                     }]
+             end};
+        _Pubsub_Node ->
+            {error, 'conflict'}
+    end.
+
+%-- Delete_Node --%
+-spec(delete_node/3 ::
+(
+  Pubsub_Host :: exmpp_pubsub:host(),
+  Entity      :: xmpp_jid:usr_bare(),
+  Parameters  :: {NodeId :: undefined | exmpp_pubsub:nodeId()})
+    -> %%
+       {result,
+        Notify :: []
+                | [Notify_Delete :: {
+                       Notification_Type::pubsub_options:notification_type(),
+                       Recipients::[Entity::xmpp_jid:usr_bare()]
+                   }]
+       }
+    %%%
+     | {error, 'item-not-found'}
+     | {error, 'forbidden'}
+).
+
+delete_node(_Pubsub_Host, _Entity, {undefined = _NodeId}) ->
+    {error, 'item-not-found'};
+%%
+delete_node(Pubsub_Host, Entity, {NodeId}) ->
+    case pubsub_db_mnesia:read_node('dev', Pubsub_Host, NodeId) of
+        undefined ->
+            {error, 'item-not-found'};
+        Pubsub_Node ->
+            case
+                lists:member(Entity, Owners = Pubsub_Node#pubsub_node_dev.owners)
+            of
+                true ->
+                    {result,
+                     _Notify = case
+                         pubsub_db_mnesia:delete_node('dev', Pubsub_Node)
+                     of
+                         undefined ->
+                             [];
+                         Subscribers ->
+                             [_Notify_Delete = {
+                                  _Notification_Type = get_value(
+                                      Pubsub_Node#pubsub_node_dev.options,
+                                          'notification_type', 'headline'),
+                                  _Recipients = lists:append(Owners, Subscribers)
+                              }]
+                     end};
+                false ->
+                    {error, 'forbidden'}
+            end
+    end.
+
+%-- Purge_Node --%
+-spec(purge_node/3 ::
+(
+  Pubsub_Host :: exmpp_pubsub:host(),
+  Entity      :: xmpp_jid:usr_bare(),
+  Parameters  :: {NodeId :: undefined | exmpp_pubsub:nodeId()})
+    -> %%
+       {result,
+        Notify :: []
+                | [Notify_Purge :: {
+                       Notification_Type::pubsub_options:notification_type(),
+                       Recipients::[Entity::xmpp_jid:usr_bare()]
+                   }]
+       }
+    %%%
+     | {error, 'item-not-found'}
+     | {error, 'forbidden'}
+     %
+     | {error, 'feature-not-implemented', 'persistent-items'}
+).
+
+purge_node(_Pubsub_Host, _Entity, {undefined = _NodeId}) ->
+    {error, 'item-not-found'};
+%%
+purge_node(Pubsub_Host, Entity, {NodeId}) ->
+    case pubsub_db_mnesia:read_node('dev', Pubsub_Host, NodeId) of
+        undefined ->
+            {error, 'item-not-found'};
+        Pubsub_Node ->
+            case lists:member(Entity, Pubsub_Node#pubsub_node_dev.owners) of
+                true ->
+                    case
+                        _Persist_Items = get_value(
+                            Node_Options = Pubsub_Node#pubsub_node_dev.options,
+                            'persist_items', true)
+                    of
+                        true ->
+                            {result,
+                             _Notify = case
+                                 pubsub_db_mnesia:purge_node('dev', Pubsub_Node)
+                             of
+                                 undefined ->
+                                     [];
+                                 Subscribers ->
+                                     [_Notify_Purge = {
+                                          _Notification_Type = get_value(
+                                              Node_Options,
+                                              'notification_type', 'headline'),
+                                          _Recipients = Subscribers
+                                     }]
+                             end};
+                        false ->
+                            {error, 'feature-not-implemented', 'persistent-items'}
+                    end;
+                false ->
+                    {error, 'forbidden'}
+            end
+    end.
+
+%-- Publish_Item --%
+-spec(publish_item/6 ::
+(
+  Host            :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host     :: exmpp_pubsub:host_pubsub(),
+  Entity          :: xmpp_jid:usr_entity(),
+  Plugin          :: exmpp_pubsub:plugin(),
+  Pubsub_Features :: exmpp_pubsub:pubsub_features(),
+  Parameters      :: {
+    NodeId  :: undefined | exmpp_pubsub:nodeId(),
+    Item    :: 0 | 1,
+    ItemId  :: undefined | exmpp_pubsub:itemId(),
+    Payload :: exmpp_pubsub:payload() | [Xmlel::xmlel(),...],
+    Options :: {Node_Options :: [] | pubsub_options:options_node(),
+                Item_Options :: [] | pubsub_options:options_item()}
+  })
+    -> {result,
+        NodeId            :: exmpp_pubsub:nodeId(),
+        ItemId            :: exmpp_pubsub:itemId(),
+        Node_Options      :: pubsub_options:options_node(),
+        Node_Owners       :: [Node_Owner::xmpp_jid:usr_bare(),...],
+        SubId             :: undefined | exmpp_pubsub:subId(),
+        Subscription      :: undefined | exmpp_pubsub:subscription_subscribed(),
+        Broadcasted_Items :: {
+          Published_Items :: [Published_Item::{
+            ItemId       :: exmpp_pubsub:itemId(),
+            Item_Options :: [] | pubsub_options:options_item(),
+            Payload      :: exmpp_pubsub:payload(),
+            Publisher    :: xmpp_jid:usr_entity()
+          }],
+          %
+          Retracted_Items :: [Retracted_Item::{
+            ItemId       :: exmpp_pubsub:itemId(),
+            Item_Options :: [] | pubsub_options:options_item()
+          }]
+        },
+        Pubsub_States::[Pubsub_State::mod_pubsub_dev:pubsub_state(),...]}
+    %%%
+     | {error, 'forbidden'}
+     | {error, 'item-not-found'}
+     %
+     | {error, 'bad-request',    'invalid-payload'}
+     | {error, 'bad-request',    'item-required'}
+     | {error, 'bad-request',    'item-forbidden'}
+     | {error, 'not-acceptable', 'payload-too-big'}
+).
+
+%%
+publish_item(Host, Pubsub_Host, {U,S,R} = Entity, Plugin, Pubsub_Features,
+  {undefined = _NodeId, Item, _ItemId, Payload,
+   {[] = _Node_Options, Item_Options}}) ->
+    case
+        pubsub_db_mnesia:read_node('dev',
+            Pubsub_Host, NodeId = exmpp_pubsub:nodeId())
+    of
+        undefined ->
+            case
+                options_on_publish_item(none, {Item, Payload,
+                    Options = {
+                        Node_Options = Plugin:node_options('leaf'),
+                        Item_Options
+                    }})
+            of
+                ok ->
+                    {ItemId, Pubsub_State} = pubsub_db_mnesia:publish_item1('dev',
+                        Pubsub_Host, Entity, NodeId, _Level = 1, _ItemId, Payload,
+                        Options, Pubsub_Features),
+                    Subscription = case
+                        Pubsub_State#pubsub_state_dev.subscriptions
+                    of
+                        []              -> undefined;
+                        [_Subscription] -> _Subscription
+                    end,
+                    {result, NodeId, ItemId, Node_Options,
+                     _Node_Owners = [{U,S,undefined}],
+                     _SubId = case Subscription of
+                         undefined ->
+                             undefined;
+                         {_Subscription_State, SubId, _Resource,
+                          _Subscription_Options} ->
+                             SubId
+                     end,
+                     Subscription,
+                     {_Published_Items = case
+                          get_value({Node_Options, Item_Options},
+                              'deliver_notifications', false)
+                      of
+                          true ->
+                              [{ItemId,
+                                Item_Options,
+                                _Payload = case
+                                    get_value({Node_Options, Item_Options},
+                                        'deliver_payloads', false)
+                                of
+                                    true  ->
+                                        case Payload of
+                                            [Xmlel] -> Xmlel;
+                                            []      -> []
+                                        end;
+                                    false -> []
+                                end,
+                                _Publisher = {U,S,R}
+                               }];
+                          false ->
+                              []
+                      end,
+                      _Retracted_Items = []},
+                     _Pubsub_States = [Pubsub_State]};
+                Error ->
+                    Error
+            end;
+        _Pusbub_Node ->
+            publish_item(Host, Pubsub_Host, {U,S,R}, Plugin, Pubsub_Features,
+                {undefined, Item, _ItemId, Payload, {[], Item_Options}})
+    end;
+
+%%
+publish_item(Host, Pubsub_Host, {U,S,R} = Entity, Plugin, Pubsub_Features,
+  {NodeId, Item, _ItemId, Payload, {[] = _Node_Options, Item_Options}}) ->
+    case pubsub_db_mnesia:read_node('dev', Pubsub_Host, NodeId) of
+        undefined ->
+            case
+                checks_on_publish_item(Host, {U,S,undefined}, Plugin,
+                    {Item, Payload, _Node_Options = [], Item_Options})
+            of
+                {ok, Pubsub_Features, Node_Options} ->
+                    Options = {Node_Options, Item_Options},
+                    {ItemId, Pubsub_State} = pubsub_db_mnesia:publish_item1('dev',
+                        Pubsub_Host, Entity, NodeId, _Level = 1, _ItemId, Payload,
+                        Options, Pubsub_Features),
+                    Subscription = case
+                        Pubsub_State#pubsub_state_dev.subscriptions
+                    of
+                        []              -> undefined;
+                        [_Subscription] -> _Subscription
+                    end,
+                    {result, NodeId, ItemId, Node_Options,
+                     _Node_Owners = [{U,S,undefined}],
+                     _SubId = case Subscription of
+                         undefined ->
+                             undefined;
+                         {_Subscription_State, SubId, _Resource,
+                          _Subscription_Options} ->
+                             SubId
+                     end,
+                     Subscription,
+                     {_Published_Items = case
+                          get_value({Node_Options, Item_Options},
+                              'deliver_notifications', false)
+                      of
+                          true ->
+                              [{ItemId,
+                                Item_Options,
+                                _Payload = case
+                                    get_value({Node_Options, Item_Options},
+                                        'deliver_payloads', false)
+                                of
+                                    true  ->
+                                        case Payload of
+                                            [Xmlel] -> Xmlel;
+                                            []      -> []
+                                        end;
+                                    false -> []
+                                end,
+                                _Publisher = {U,S,R}
+                               }];
+                          false ->
+                              []
+                      end,
+                      _Retracted_Items = []},
+                     _Pubsub_States = [Pubsub_State]};
+                Error ->
+                    Error
+            end;
+        Pubsub_Node ->
+            NodeIdx = Pubsub_Node#pubsub_node_dev.idx,
+            Pubsub_State = pubsub_db_mnesia:read_state('dev',
+                {U,S,undefined}, NodeIdx),
+            case
+                options_on_publish_item(Host, Entity,
+                    _Affiliation = case Pubsub_State of
+                        undefined -> 'none';
+                        _         -> Pubsub_State#pubsub_state_dev.affiliation
+                    end,
+                    _Subscriptions = case Pubsub_State of
+                        undefined -> [];
+                        _         -> Pubsub_State#pubsub_state_dev.subscriptions
+                    end,
+                    _Options = {
+                        Node_Options = Pubsub_Node#pubsub_node_dev.options,
+                        Item_Options
+                    },
+                    Node_Owners = Pubsub_Node#pubsub_node_dev.owners,
+                    Item,
+                    Payload) 
+            of
+                ok ->
+                    {ItemId, Retracted_Items, Pubsub_States} =
+                        pubsub_db_mnesia:publish_item2('dev', Pubsub_Host,
+                            {U,S,R}, Pubsub_State, Pubsub_Node,
+                            case _ItemId of
+                                undefined ->
+                                    undefined;
+                                _ ->
+                                    case
+                                        pubsub_db_mnesia:read_item('dev',
+                                            NodeIdx, _ItemId)
+                                    of
+                                        undefined   -> _ItemId;
+                                        Pubsub_Item -> Pubsub_Item
+                                    end
+                            end,
+                            Payload, Item_Options, Pubsub_Features),
+                    {result, NodeId, ItemId, Node_Options, Node_Owners,
+                     _SubId = undefined, _Subscription = undefined,
+                     {_Published_Items = case
+                          get_value({Node_Options, Item_Options},
+                              'deliver_notifications', false)
+                      of
+                          true ->
+                              [{ItemId,
+                                Item_Options,
+                                _Payload = case
+                                    get_value({Node_Options, Item_Options},
+                                        'deliver_payloads', false)
+                                of
+                                    true  ->
+                                        case Payload of
+                                            [Xmlel] -> Xmlel;
+                                            []      -> []
+                                        end;
+                                    false -> []
+                                end,
+                                _Publisher = {U,S,R}
+                               }];
+                          false ->
+                              []
+                      end,
+                      Retracted_Items},
+                     Pubsub_States};
+                Error ->
+                    Error
+            end
+    end.
+
+
+%%
+-spec(options_on_publish_item/8 ::
+(
+  Host          :: xmpp_jid:raw_jid_component_bare(),
+  Entity        :: xmpp_jid:usr_bare(),
+  Affiliation   :: exmpp_pubsub:affiliation(),
+  Subscriptions :: exmpp_pubsub:subscriptions(),
+  Options       :: {Node_Options :: pubsub_options:options_node(),
+                    Item_Options :: [] | pubsub_options:options_item()},
+  Node_Owners   :: [Node_Owner::xmpp_jid:usr_bare(),...],
+  Item          :: 0 | 1,
+  Payload       :: exmpp_pubsub:payload() | [Xmlel::xmlel(),...])
+    -> ok
+    %%%
+     | {error, 'forbidden'}
+     | {error, 'item-not-found'}
+     %
+     | {error, 'bad-request',    'invalid-payload'}
+     | {error, 'bad-request',    'item-required'}
+     | {error, 'bad-request',    'item-forbidden'}
+     | {error, 'not-acceptable', 'payload-too-big'}
+).
+
+options_on_publish_item(_Host, _Entity, 'owner' = _Affiliation, _Subscriptions,
+  Options, _Node_Owners, Item, Payload) ->
+    options_on_publish_item(none, {Item, Payload, Options});
+%%
+options_on_publish_item(Host, Entity, 'outcast' = _Affiliation, _Subscriptions,
+  {Node_Options, _Item_Options}, Node_Owners, _Item, _Payload) ->
+    case get_value(Node_Options, 'access_model') of
+        %%
+        'open'->
+              {error, 'forbidden'};
+        %%
+        'presence' ->
+            case
+                is_contact_subscribed_to_node_owners(Host, Entity, Node_Owners)
+            of
+                false ->
+                    {error, 'item-not-found'};
+                _Node_Owner ->
+                    {error, 'forbidden'}
+            end;
+        %%
+        'roster' ->
+            case
+                is_contact_in_allowed_roster_groups(Entity,
+                    _Rosters_Groups_Allowed = get_value(Node_Options,
+                        'roster_groups_allowed'))
+            of
+                false ->
+                    {error, 'item-not-found'};
+                {_Node_Owner, _Roster_Group_Allowed} ->
+                    {error, 'forbidden'}
+            end;
+        %%
+        'authorize' ->
+            {error, 'forbidden'};
+        %%
+        'whitelist' ->
+            {error, 'item-not-found'}
+    end;
+%%
+options_on_publish_item(Host, Entity, Affiliation, Subscriptions,
+  {Node_Options, Item_Options} = _Options, Node_Owners, Item, Payload) ->
+    %% 'pubsub#access_model'
+    case
+        check_access_model(Host, Entity,
+            _Access_Model = get_value(Node_Options, 'access_model'),
+            Affiliation, Subscriptions, Node_Owners,
+            _Rosters_Groups_Allowed = get_value(Node_Options,
+                'roster_groups_allowed'))
+    of
+        ok ->
+            %% 'pubsub#publish_model'
+            case
+                check_publish_model(
+                    _Publish_Model = get_value(Node_Options, 'publish_model'),
+                    Affiliation, Subscriptions)
+            of
+                ok ->
+                    options_on_publish_item(none,
+                        {Item, Payload, {Node_Options, Item_Options}});
+                Error ->
+                    Error
+            end;
+        Error ->
+            Error
+    
+    end.
+
+%%
+-spec(options_on_publish_item/2 ::
+(
+
+  Option   :: none
+            | {pubsub_options:option_node_deliver_payloads(),
+               pubsub_options:option_node_persist_items()}
+            | pubsub_options:option_node_max_payload_size()
+            | pubsub_options:option_node_type(),
+           %%
+  Criteria :: {Item    :: 0 | 1, 
+               Payload :: exmpp_pubsub:payload() | [Xmlel::xmlel(),...],
+               Options :: {Node_Options :: pubsub_options:options_node(),
+                           Item_Options :: [] | pubsub_options:options_item()}}
+            | {Item    :: 0 | 1, 
+               Payload :: exmpp_pubsub:payload(),
+               Options :: {Node_Options :: pubsub_options:options_node(),
+                           Item_Options :: [] | pubsub_options:options_item()}}
+            %
+            | {Payload :: exmpp_pubsub:payload(),
+               Options :: {Node_Options :: pubsub_options:options_node(),
+                           Item_Options :: [] | pubsub_options:options_item()}}
+            %
+            | {Payload :: exmpp_pubsub:payload()})
+    -> %%
+       ok
+    %%%
+     | {error, 'bad-request',    'invalid-payload'}
+     | {error, 'bad-request',    'item-required'}
+     | {error, 'bad-request',    'payload-required'}
+     | {error, 'bad-request',    'item-forbidden'}
+     | {error, 'not-acceptable', 'payload-too-big'}
+).
+
+%% Payloads count
+options_on_publish_item(none, {Item, [] = Payload, Options}) ->
+    options_on_publish_item(
+        {get_option(Options, 'deliver_payloads', false),
+         get_option(Options, 'persist_items', false)},
+        {Item, Payload, Options});
+%%
+options_on_publish_item(none, {Item, [Payload], Options}) ->
+    options_on_publish_item(
+        {get_option(Options, 'deliver_payloads', false),
+         get_option(Options, 'persist_items', false)},
+        {Item, Payload, Options});
+%%
+options_on_publish_item(none, _Parameters) ->
+    {error, 'bad-request', 'invalid-payload'};
+%%
+%% 'pubsub#deliver_payloads'
+%% 'pubsub#persist_items'
+options_on_publish_item(
+  {{'deliver_payloads', _Deliver_Payloads}, {'persist_items', true}},
+  {0 = _Item, _Payload, _Options}) ->
+    {error, 'bad-request', 'item-required'};
+%%
+options_on_publish_item(
+  {{'deliver_payloads', true}, {'persist_items', _Persist_Items}},
+  {_Item, [] = _Payload, _Options}) ->
+    {error, 'bad-request', 'payload-required'};
+%%
+options_on_publish_item(
+  {{'deliver_payloads', false}, {'persist_items', false}},
+  {1 = _Item, _Payload, _Options}) ->
+    {error, 'bad-request', 'item-forbidden'};
+%%
+options_on_publish_item(
+  {{'deliver_payloads', Deliver_Payloads}, {'persist_items', Persist_Items}},
+  {_Item, [] = _Payload, Options}) ->
+    ok;
+%%
+options_on_publish_item(
+  {{'deliver_payloads', Deliver_Payloads}, {'persist_items', Persist_Items}},
+  {_Item, Payload, {Node_Options, Item_Options} = _Options}) ->
+    options_on_publish_item(
+        _Max_Payload_Size = get_option(Node_Options, 'max_payload_size', 0),
+        {Payload, {Node_Options, Item_Options}});
+%% 'pubsub#max_payload_size'
+options_on_publish_item({'max_payload_size', Max_Payload_Size},
+  {Payload, Options}) ->
+    case byte_size(term_to_binary(Payload)) =< Max_Payload_Size of
+        true ->
+            options_on_publish_item(get_option(Options, 'type', undefined),
+                {Payload});
+        false ->
+            {error, 'not-acceptable', 'payload-too-big'}
+    end;
+%% 'pubsub#type'
+options_on_publish_item({'type', Type}, {Payload})
+  when   Type == undefined ->
+  %%orelse Type == Payload#xmlel.ns ->
+      ok;
+%%
+options_on_publish_item(_, _) ->
+    {error, 'bad-request', 'invalid-payload'}.
+
+
+
+%%
+-spec(checks_on_publish_item/4 ::
+(
+  Host       :: xmpp_jid:raw_jid_component_bare(),
+  Entity     :: xmpp_jid:usr_entity(),
+  Plugin     :: exmpp_pubsub:plugin(),
+  Parameters :: {Item         :: 0 | 1,
+                 Payload      :: [Xmlel::xmlel()],
+                 Node_Options :: [],
+                 Item_Options :: [] | pubsub_options:options_item()})
+    -> {ok,
+        Pubsub_Features :: exmpp_pubsub:pubsub_features(),
+        Node_Options    :: pubsub_options:options_node()}
+    %%%
+     | {error, 'forbidden'}
+     | {error, 'item-not-found'}
+     %
+     | {error, 'bad-request',    'invalid-payload'}
+     | {error, 'bad-request',    'item-required'}
+     | {error, 'bad-request',    'item-forbidden'}
+     | {error, 'not-acceptable', 'payload-too-big'}
+).
+
+
+checks_on_publish_item({U,S,_} = _Host, {U,S,_} = _Entity, Plugin,
+  {Item, Payload, [] = _Node_Options, Item_Options}) ->
+    case
+        lists:member(<<"auto-create">>, Pubsub_Features = Plugin:pubsub_features())
+    of
+        true ->
+            case
+                options_on_publish_item(none,
+                    {Item,
+                     Payload,
+                     _Options = {
+                         Node_Options = Plugin:node_options('leaf'),
+                         Item_Options
+                     }})
+            of
+                ok    -> {ok, Pubsub_Features, Node_Options};
+                Error -> Error
+            end;
+        false ->
+            {error, 'item-not-found'}
+    end;
+%%
+checks_on_publish_item(_Host, _Entity, _Plugin, _Parameters)
+  when is_tuple(_Host) ->
+    {error, 'foribdden'};
+%%
+checks_on_publish_item(Host, {U,S,_R} = _Entity, Plugin,
+  {Item, Payload, [] = _Node_Options, Item_Options}) ->
+    case acl:match_rule(Host, pubsub_createnode, jlib:jid_to_string({U,S, <<>>})) of
+        allow ->
+            case
+                lists:member(<<"auto-create">>,
+                    Pubsub_Features = Plugin:pubsub_features())
+            of
+                true ->
+                    case
+                        options_on_publish_item(none,
+                            {Item, Payload,
+                             _Options = {
+                                 Node_Options = Plugin:node_options('leaf'),
+                                 Item_Options
+                             }})
+                    of
+                        ok    -> {ok, Pubsub_Features, Node_Options};
+                        Error -> Error
+                    end;
+                false ->
+                    {error, 'item-not-found'}
+            end;
+        _Deny ->
+            {error, 'forbidden'}
+    end.
+
+%-- Retract_Item --%
+-spec(retract_item/3 ::
+(
+  Pubsub_Host :: exmpp_pubsub:host(),
+  Entity      :: xmpp_jid:usr_bare(),
+  Parameters  :: {NodeId               :: undefined | exmpp_pubsub:nodeId(),
+                  ItemId               :: undefined | exmpp_pubsub:itemId(),
+                  Adhoc_Notify_Retract :: undefined | boolean()})
+    -> {result,
+        Notify :: []
+                | [Notify_Retract :: {
+                       Node_Owners   :: [Entity::xmpp_jid:usr_bare(),...],
+                       Node_Options  :: pubsub_options:options_node(),
+                       Item_Options  :: [] | pubsub_options:options_item(),
+                       Pubsub_States :: mod_pubsub_dev:pubsub_states()
+                   }]}
+    %%%
+     | {error, 'bad-request', 'nodeid-required'}
+     | {error, 'bad-request', 'item-required'}
+     %
+     | {error, 'item-not-found'}
+     | {error, 'forbidden'}
+).
+
+retract_item(_Pubsub_Host, _Entity,
+  {undefined = _NodeId, _ItemId, _Adhoc_Notify_Retract}) ->
+    {error, 'bad-request', 'nodeid-required'};
+%%
+retract_item(_Pubsub_Host, _Entity,
+  {_NodeId, undefined = _ItemId, _Adhoc_Notify_Retract}) ->
+    {error, 'bad-request', 'item-required'};
+%%
+retract_item(Pubsub_Host, Entity, {NodeId, ItemId, Adhoc_Notify_Retract}) ->
+    case pubsub_db_mnesia:read_node('dev', Pubsub_Host, NodeId) of
+        undefined ->
+            {error, 'item-not-found'};
+        Pubsub_Node ->
+            case
+                pubsub_db_mnesia:read_state('dev', Entity,
+                    Pubsub_Node#pubsub_node_dev.idx)
+            of
+                Pubsub_State
+                  when   Pubsub_State == undefined
+                  orelse Pubsub_State#pubsub_state_dev.affiliation == 'outcast' ->
+                    {error, 'forbidden'};
+                Pubsub_State ->
+                    case
+                        pubsub_db_mnesia:retract_item('dev', Pubsub_Node,
+                            Pubsub_State, ItemId, Adhoc_Notify_Retract)
+                    of
+                        {ok, undefined} ->
+                            {result, _Notify = []};
+                        {ok, Item_Options, Pubsub_States} ->
+                            {result,
+                             _Notify = [_Notify_Retract = {
+                                 _Node_Owners = Pubsub_Node#pubsub_node_dev.owners,
+                                 _Node_Options = Pubsub_Node#pubsub_node_dev.options,
+                                 Item_Options,
+                                 Pubsub_States
+                             }]
+                            };
+                        Error ->
+                            Error
+                    end
+            end
+    end.
+
+
+%-- Subscribe_Node --%
+-spec(subscribe_node/7 ::
+(
+  Host            :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host     :: exmpp_pubsub:host(),
+  Entity          :: xmpp_jid:usr_bare(),
+  Plugin          :: exmpp_pubsub:plugin(),
+  Options_Module  :: module(),
+  Pubsub_Features :: exmpp_pubsub:pubsub_features(),
+  Parameters      :: {NodeId            :: exmpp_pubsub:nodeId(),
+                      Resource          :: undefined | xmpp_jid:resource_jid(),
+                      Subscribe_Options :: [Xmlel::xmlel(),...]
+                                         | [Xmlel::xmlel()]})
+    -> {result,
+        Subscription_Subscribed :: exmpp_pubsub:subscription_subscribed(),
+        Affiliation             :: 'member' | 'owner' | 'publisher',
+        Node_Owners             :: [Entity::xmpp_jid:usr_bare(),...],
+        Node_Options            :: pubsub_options:options_node(),
+        Pubsub_Last_Item        :: undefined | mod_pubsub_dev:pubsub_last_item()}
+     %
+     | {result,
+        Subscription_Pending :: exmpp_pubsub:subscription_pending(),
+        Affiliation          :: 'member',
+        Node_Owners          :: [Entity::xmpp_jid:usr_bare(),...],
+        Node_Options         :: pubsub_options:options_node(),
+        Pubsub_Last_Item     :: undefined}
+    %%%
+     | {error, 'item-not-found'}
+     | {error, 'forbidden'}
+     %
+     | {error, 'invalid-options'}
+     | {error, 'not-acceptable'}
+     %
+     | {error, 'not-authorized', 'presence-subscription-required'}
+     | {error, 'not-authorized', 'not-in-roster-group'}
+     | {error, 'not-authorized', 'pending-subscription'}
+     | {error, 'not-allowed',    'closed-node'}
+).
+
+subscribe_node(_Host, _Pubsub_Host, _Entity, _Plugin, _Options_Module,
+  _Pubsub_Features, {undefined = _NodeId, _Resource, _Subscribe_Options}) ->
+    {error, 'item-not-found'};
+%%
+subscribe_node(Host, Pubsub_Host, {_, S,_} = Entity, Plugin, Options_Module,
+  Pubsub_Features, {NodeId, Resource, Subscribe_Options}) ->
+    case pubsub_db_mnesia:read_node('dev', Pubsub_Host, NodeId) of
+        undefined ->
+            {error, 'item-not-found'};
+        #pubsub_node_dev{idx = NodeIdx, owners = Node_Owners, options = Node_Options} ->
+            case
+                Options_Module:parse_xmlel_x(Plugin, Pubsub_Features, Entity,
+                    _Entity_Type = case S == Host of
+                        true  -> 'local';
+                        false -> 'remote'
+                    end,
+                    'subscribe_options',
+                    _Node_Type = get_value(Node_Options, 'node_type', 'leaf'),
+                    Subscribe_Options)
+            of
+                {ok, Subscription_Options} ->
+                    Pubsub_State = case
+                        pubsub_db_mnesia:read_state('dev', Entity, NodeIdx)
+                    of
+                        undefined ->
+                            #pubsub_state_dev{
+                                id      = {Entity, NodeIdx},
+                                nodeidx = NodeIdx
+                            };
+                        _Pubsub_State ->
+                            _Pubsub_State
+                    end,
+                    case
+                        pubsub_db_mnesia:subscribe_node('dev', Host, Node_Options,
+                            Node_Owners, Pubsub_State, Resource,
+                            Subscription_Options, Pubsub_Features)
+                    of
+                        {result, Subscription, Pubsub_Last_Item} ->
+                            {result,
+                             Subscription,
+                             case Pubsub_State#pubsub_state_dev.affiliation of
+                                'none'      -> 'member';
+                                Affiliation -> Affiliation
+                             end,
+                             Node_Owners, Node_Options, Pubsub_Last_Item};
+                        Error ->
+                            Error
+                    end;
+                Error ->
+                    Error
+            end
+    end.
+
+%-- Unsubscribe_Node --%
+-spec(unsubscribe_node/4 ::
+(
+  Host            :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host     :: exmpp_pubsub:host(),
+  Entity          :: xmpp_jid:usr_bare(),
+  Parameters      :: {NodeId    :: exmpp_pubsub:nodeId(),
+                      _Resource :: undefined
+                                 | xmpp_jid:resource_jid()
+                                 | {'caps', xmpp_jid:resource_jid()},
+                      _SubId    :: exmpp_pubsub:subId()})
+    -> {result,
+        SubId :: exmpp_pubsub:subId()}
+     |
+       {result,
+        SubId             :: exmpp_pubsub:subId(),
+        Node_Owners       :: [Entity::xmpp_jid:usr_bare(),...],
+        Notification_Type :: pubsub_options:notification_type()}
+    %%%
+     | {error, 'item-not-found'}
+     | {error, 'forbidden'}
+     | {error, 'unexpected',     'not-subscribed'}
+     %
+     | {error, 'unexpected',     'not-subscribed'}
+     | {error, 'not-acceptable', 'invalid-subid'}
+     | {error, 'bad-request',    'subid-required'}
+     | {error, 'not-acceptable', 'invalid-subid'}
+).
+
+unsubscribe_node(_Host, _Pubsub_Host, _Entity,
+  {undefined = _NodeId, _Resource, _SubId}) ->
+    {error, 'item-not-found'};
+%%
+unsubscribe_node(Host, Pubsub_Host, Entity, {NodeId, _Resource, _SubId}) ->
+    case pubsub_db_mnesia:read_node('dev', Pubsub_Host, NodeId) of
+        undefined ->
+            {error, 'item-not-found'};
+        #pubsub_node_dev{idx = NodeIdx, owners = Node_Owners, options = Node_Options} ->
+            case pubsub_db_mnesia:read_state('dev', Entity, NodeIdx) of
+                Pubsub_State
+                  when   Pubsub_State == undefined
+                  orelse Pubsub_State#pubsub_state_dev.affiliation   == 'none'
+                  orelse Pubsub_State#pubsub_state_dev.subscriptions == [] ->
+                    {error, 'unexpected', 'not-subscribed'};
+                Pubsub_State
+                  when Pubsub_State#pubsub_state_dev.affiliation == 'publish-only'->
+                    {error, 'forbidden'};
+                Pubsub_State ->
+                    case
+                        pubsub_db_mnesia:unsubscribe_node('dev', Host,
+                            _Node_Access_Model = get_value(Node_Options, 'access_model'),
+                            Pubsub_State, _Resource, _SubId)
+                    of
+                        {ok, Resource, SubId} ->
+                            case get_value(Node_Options, 'notify_sub', false) of
+                                true ->
+                                    {result, SubId, Node_Owners,
+                                     get_value(Node_Options, 'notification_type',
+                                         'headline')};
+                                false ->
+                                    {result, SubId}
+                            end;
+                        Error ->
+                            Error
+                    end
+            end
+    end.
+
+%-- Set_Configure_Subscription --%
+-spec(set_configure_subscription/7 ::
+(
+  Host            :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host     :: exmpp_pubsub:host(),
+  Entity          :: xmpp_jid:usr_bare(),
+  Plugin          :: exmpp_pubsub:plugin(),
+  Options_Module  :: module(),
+  Pubsub_Features :: exmpp_pubsub:pubsub_features(),
+  Parameters      :: {NodeId            :: undefined | exmpp_pubsub:nodeId(),
+                      SubId             :: undefined | exmpp_pubsub:subId(),
+                      Resource          :: undefined
+                                         | xmpp_jid:resource_jid()
+                                         | {'caps', xmpp_jid:resource_jid()},
+                      Subscribe_Options :: [Xmlel::xmlel(),...]
+                                         | [Xmlel::xmlel()]})
+    -> {result, []}
+    %%%
+     | {error, 'item-not-found'}
+     | {error, 'unexpected-request', 'not-subscribed'}
+     | {error, 'forbidden'}
+     | {error, 'bad-request', 'invalid-options'}
+     %
+     | {error, 'unexpected-request', 'not-subscribed'}
+     | {error, 'bad-request',        'subid-required'}
+     | {error, 'forbidden'}
+     | {error, 'not-acceptable',     'invalid-subid'}
+).
+
+set_configure_subscription(_Host, _Pubsub_Host, _Entity, _Plugin, _Options_Module,
+  _Pubsub_Features, {undefined = _NodeId, _SubId, _Resource, _Subscribe_Options}) ->
+    {error, 'item-not-found'};
+%%
+set_configure_subscription(Host, Pubsub_Host, {_,S,_} = Entity, Plugin, Options_Module,
+  Pubsub_Features, {NodeId, SubId, Resource, Subscribe_Options}) ->
+    case pubsub_db_mnesia:read_node('dev', Pubsub_Host, NodeId) of
+        undefined ->
+            {error, 'item-not-found'};
+        #pubsub_node_dev{idx = NodeIdx, owners = Node_Owners, options = Node_Options} ->
+            case pubsub_db_mnesia:read_state('dev', Entity, NodeIdx) of
+                undefined ->
+                    {error, 'unexpected-request', 'not-subscribed'};
+                #pubsub_state_dev{affiliation = Affiliation}
+                  when   Affiliation == 'publish-only'
+                  orelse Affiliation == 'outcast' ->
+                    {error, 'forbidden'};
+                #pubsub_state_dev{subscriptions = []} ->
+                    {error, 'unexpected-request', 'not-subscribed'};
+                Pubsub_State ->
+                    case
+                        Options_Module:parse_xmlel_x(Plugin, Pubsub_Features, Entity,
+                            _Entity_Type = case S == Host of
+                                true  -> 'local';
+                                false -> 'remote'
+                            end,
+                            'subscribe_options',
+                            _Node_Type = get_value(Node_Options, 'node_type', 'leaf'),
+                            Subscribe_Options)
+                    of
+                        {ok, Subscription_Options} ->
+                            case
+                                pubsub_db_mnesia:set_configure_subscription('dev',
+                                    Pubsub_State, SubId, Resource,
+                                    Subscription_Options) 
+                            of
+                                ok ->
+                                    {result, []};
+                                Error ->
+                                    Error
+                            end;
+                        _Error ->
+                            {error, 'bad-request', 'invalid-options'}
+                    end
+            end
+    end.
+
+%-- Get_Items --%
+-spec(get_items/4 ::
+(
+  Host        :: xmpp_jid:raw_jid_component_bare(),
+  Pusbub_Host :: exmpp_pubsub:host(),
+  Entity      :: xmpp_jid:usr_bare(),
+  Parameters  :: {NodeId    :: undefined | exmpp_pubsub:nodeId(),
+                  _SubId    :: undefined | exmpp_pubsub:subId(),
+                  Max_Items :: non_neg_integer(),
+                  ItemIds   :: undefined}
+               | {NodeId    :: undefined | exmpp_pubsub:nodeId(),
+                  _SubId    :: undefined | exmpp_pubsub:subId(),
+                  Max_Items :: undefined,
+                  ItemIds   :: [] | exmpp_pubsub:itemIds()})
+    -> {result,
+        Pubsub_Items      :: [] | mod_pubsub_dev:pubsub_items(),
+        Cache             :: {Presence_Cache :: undefined,
+                              Groups_Cache   :: undefined}
+                           | {Presence_Cache :: true,
+                              Groups_Cache   :: undefined}
+                           | {Presence_Cache :: undefined,
+                              Groups_Cache   :: [{Node_Owner :: xmpp_jid:usr_bare(),
+                                                  Groups     :: [Group::binary()]}]},
+        Node_Owners       :: mod_pubsub_dev:node_owners(),
+        Node_Access_Model :: pubsub_options:access_model(),
+        Node_Groups       :: pubsub_options:rosters_groups_allowed(),
+        Affiliation       :: exmpp_pubsub:affiliation(),
+        Access            :: undefined | 'presence' | 'roster' | 'pending' | 'authorize'}
+    %%%
+     | {error, 'item-not-found'}
+     | {error, 'forbidden'}
+     | {error, 'not-authorized', 'presence-subscription-required'}
+     | {error, 'not-authorized', 'not-in-roster-group'}
+     | {error, 'not-allowed',    'closed-node'}
+).
+
+get_items(_Host, _Pubsub_Host, _Entity,
+  {undefined = _NodeId, _SubId, _Max_Items, _ItemIds}) ->
+    {error, 'item-not-found'};
+%%
+get_items(Host, Pubsub_Host, Entity, {NodeId, _SubId, Max_Items, ItemIds}) ->
+    case pubsub_db_mnesia:read_node('dev', Pubsub_Host, NodeId) of
+        undefined ->
+            {error, 'item-not-found'};
+        #pubsub_node_dev{idx = NodeIdx, owners = Node_Owners,
+         options = Node_Options, itemids = Node_ItemIds} ->
+            {Affiliation, Access} = case lists:member(Entity, Node_Owners) of
+                true ->
+                    {'owner', undefined};
+                false ->
+                    case pubsub_db_mnesia:read_state('dev', Entity, NodeIdx) of
+                        undefined ->
+                            {'none', undefined};
+                        #pubsub_state_dev{affiliation = _Affiliation,
+                         access = _Access} ->
+                            {_Affiliation, _Access}
+                    end
+            end,
+            Node_Access_Model = get_value(Node_Options, 'access_model'),
+            Node_Groups = get_value(Node_Options, 'roster_groups_allowed', []),
+            case
+                pubsub_db_mnesia:get_items('dev', Host,
+                    {NodeIdx, Node_Owners, Node_ItemIds, Node_Access_Model, Node_Groups},
+                    {Entity, Affiliation, Access},
+                    {Max_Items, ItemIds, _SubId})
+            of
+                {ok, Pubsub_Items, Cache} ->
+                    {result, Pubsub_Items, Cache, Node_Owners, Node_Access_Model,
+                     Node_Groups, Affiliation, Access};
+                Error ->
+                    Error
+            end
+    end.
+
+%-- Get_Entity_Affiliations --%
+-spec(get_entity_affiliations/3 ::
+(
+  Pubsub_Host :: exmpp_pubsub:host(),
+  Entity      :: xmpp_jid:usr_bare(),
+  Parameters  :: {NodeId :: undefined | exmpp_pubsub:nodeId()})
+    -> Entity_Affiliations :: [Entity_Affiliation :: {
+           NodeId      :: exmpp_pubsub:nodeId(),
+           Affiliation :: exmpp_pubsub:affiliation()
+       }]
+).
+
+get_entity_affiliations(Pubsub_Host, Entity, {NodeId}) ->
+    pubsub_db_mnesia:get_entity_affiliations('dev', Pubsub_Host, Entity, NodeId).
+
+%-- Get_Entity_Subscriptions --%
+-spec(get_entity_subscriptions/3 ::
+(
+  Pubsub_Host :: exmpp_pubsub:host(),
+  Entity      :: xmpp_jid:usr_bare(),
+  Parameters  :: {NodeId :: undefined | exmpp_pubsub:nodeId()})
+    -> Entity_Subscriptions :: [{
+           NodeId        :: exmpp_pubsub:nodeId(),
+           Subscriptions :: _%exmpp_pubsub:subscriptions()
+       }]
+).
+
+get_entity_subscriptions(Pubsub_Host, Entity, {NodeId}) ->
+    pubsub_db_mnesia:get_entity_subscriptions('dev', Pubsub_Host, Entity, NodeId).
+
+
+%-- Get_Node_Affiliations --%
+-spec(get_node_affiliations/4 ::
+(
+  Host        :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host :: exmpp_pubsub:host(),
+  Entity      :: xmpp_jid:usr_bare(),
+  Parameters  :: {NodeId :: undefined | exmpp_pubsub:nodeId()})
+    -> {result, Pubsub_States::[Pubsub_State::mod_pubsub_dev:pubsub_state(),...]}
+    %%%
+     | {error, 'item-not-found'}
+     | {error, 'forbidden'}
+
+).
+
+get_node_affiliations(_Host, _Pubsub_Host, _Entity, {undefined = _NodeId}) ->
+    {error, 'item-not-found'};
+%%
+get_node_affiliations(Host, Pubsub_Host, Entity, {NodeId}) ->
+    case pubsub_db_mnesia:read_node('dev', Pubsub_Host, NodeId) of
+        undefined ->
+            {error, 'item-not-found'};
+        #pubsub_node_dev{idx = NodeIdx, owners = Owners, options = Options} ->
+            case lists:member(Entity, Owners) of
+                true ->
+                    {result,
+                     _Pubsub_States = pubsub_db_mnesia:index_read_state('dev',
+                         NodeIdx)};
+                false ->
+                    %% Depending on the node access_model, the returned error
+                    %% can be 'forbidden' or 'item-not-found' to not disclose
+                    %% private nodes
+                    case get_value(Options, 'access_model') of
+                        %%
+                        'open' ->
+                            {error, 'forbidden'};
+                        %%
+                        'presence' ->
+                            case
+                                is_contact_subscribed_to_node_owners(Host,
+                                    Entity, Owners)
+                            of
+                                false ->
+                                    {error, 'item-not-found'};
+                                _Node_Owner ->
+                                    {error, 'forbidden'}
+                            end;
+                        %%
+                        'roster' ->
+                            case
+                                is_contact_in_allowed_roster_groups(Entity,
+                                    _Rosters_Groups_Allowed = get_value(
+                                         Options, 'roster_groups_allowed'))
+                            of
+                                false ->
+                                    {error, 'item-not-found'};
+                                {_Node_Owner, _Roster_Group_Allowed} ->
+                                    {error, 'forbidden'}
+                            end;
+                        %%
+                        'authorize' ->
+                            {error, 'forbidden'};
+                        %%
+                        'whitelist' ->
+                            case
+                                pubsub_db_mnesia:read_state('dev', Entity, NodeIdx)
+                            of
+                                #pubsub_state_dev{affiliation = Affiliation}
+                                  when   Affiliation == 'member'
+                                  orelse Affiliation == 'publish-only'
+                                  orelse Affiliation == 'publisher' ->
+                                    {error, 'forbidden'};
+                                _Pubsub_State ->
+                                    {error, 'item-not-found'}
+                            end
+                    end
+            end
+    end.
+
+%-- Get_Node_Subscriptions --%
+-spec(get_node_subscriptions/4 ::
+(
+  Host        :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host :: exmpp_pubsub:host(),
+  Entity      :: xmpp_jid:usr_bare(),
+  Parameters  :: {NodeId :: undefined | exmpp_pubsub:nodeId()})
+    -> {result, Pubsub_States::[Pubsub_State::mod_pubsub_dev:pubsub_state(),...]}
+    %%%
+     | {error, 'item-not-found'}
+     | {error, 'forbidden'}
+
+).
+
+get_node_subscriptions(_Host, _Pubsub_Host, _Entity, {undefined = _NodeId}) ->
+    {error, 'item-not-found'};
+%%
+get_node_subscriptions(Host, Pubsub_Host, Entity, {NodeId}) ->
+    case pubsub_db_mnesia:read_node('dev', Pubsub_Host, NodeId) of
+        undefined ->
+            {error, 'item-not-found'};
+        #pubsub_node_dev{idx = NodeIdx, owners = Owners, options = Options} ->
+            case lists:member(Entity, Owners) of
+                true ->
+                    {result,
+                     _Pubsub_States = pubsub_db_mnesia:index_read_state('dev',
+                         NodeIdx)};
+                false ->
+                    %% Depending on the node access_model, the returned error
+                    %% can be 'forbidden' or 'item-not-found' to not disclose
+                    %% private nodes
+                    case get_value(Options, 'access_model') of
+                        %%
+                        'open' ->
+                            {error, 'forbidden'};
+                        %%
+                        'presence' ->
+                            case
+                                is_contact_subscribed_to_node_owners(Host,
+                                    Entity, Owners)
+                            of
+                                false ->
+                                    {error, 'item-not-found'};
+                                _Node_Owner ->
+                                    {error, 'forbidden'}
+                            end;
+                        %%
+                        'roster' ->
+                            case
+                                is_contact_in_allowed_roster_groups(Entity,
+                                    _Rosters_Groups_Allowed = get_value(Options,
+                                        'roster_groups_allowed'))
+                            of
+                                false ->
+                                    {error, 'item-not-found'};
+                                {_Node_Owner, _Roster_Group_Allowed} ->
+                                    {error, 'forbidden'}
+                            end;
+                        %%
+                        'authorize' ->
+                            {error, 'forbidden'};
+                        %%
+                        'whitelist' ->
+                            case
+                                pubsub_db_mnesia:read_state('dev', Entity, NodeIdx)
+                            of
+                                #pubsub_state_dev{affiliation = Affiliation}
+                                  when   Affiliation == 'member'
+                                  orelse Affiliation == 'publish-only'
+                                  orelse Affiliation == 'publisher' ->
+                                    {error, 'forbidden'};
+                                _Pubsub_State ->
+                                    {error, 'item-not-found'}
+                            end
+                    end
+            end
+    end.
+
+%% Get_Configure_Subscription_Default
+-spec(get_configure_subscription_default/4 ::
+(
+  Host        :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host :: exmpp_pubsub:host(),
+  Entity      :: xmpp_jid:usr_bare(),
+  NodeId      :: exmpp_pubsub:nodeId())
+    -> ok
+    %%%
+     | {error, 'item-not-found'}
+     | {error, 'forbidden'}
+).
+
+get_configure_subscription_default(Host, Pubsub_Host, Entity, NodeId) ->
+    case pubsub_db_mnesia:read_node('dev', Pubsub_Host, NodeId) of
+        undefined ->
+            {error, 'item-not-found'};
+        #pubsub_node_dev{idx = NodeIdx, owners = Node_Owners, options = Node_Options} ->
+            case lists:member(Entity, Node_Owners) of
+                true ->
+                    ok;
+                false ->
+                    Node_Access_Model = get_value(Node_Options, 'access_model'),
+                    case pubsub_db_mnesia:read_state('dev', Entity, NodeIdx) of
+                        undefined
+                          when Node_Access_Model == 'open' ->
+                            ok;
+                        undefined
+                          when Node_Access_Model == 'presence' ->
+                            case
+                                is_contact_subscribed_to_node_owners(Host,
+                                    Entity, Node_Owners)
+                            of
+                                false       -> {error, 'forbidden'};
+                                _Node_Owner ->  ok
+                            end;
+                        undefined
+                          when Node_Access_Model == 'roster' ->
+                            case
+                                is_contact_in_allowed_roster_groups(Entity,
+                                    _Rosters_Groups_Allowed =
+                                        get_value(Node_Options,
+                                            'roster_groups_allowed', []))
+                            of
+                                false -> {error, 'forbidden'};
+                                _     -> ok
+                            end;
+                        undefined ->
+                            {error, 'forbidden'};
+                        #pubsub_state_dev{affiliation = Affiliation,
+                         access = Access}
+                          when    Affiliation == 'publisher'
+                          orelse  Affiliation == 'member'
+                          orelse (Affiliation == 'none'
+                                      andalso
+                                  Node_Access_Model == 'open')
+                          orelse Access == 'presence'
+                          orelse Access == 'roster' ->
+                            ok;
+                        #pubsub_state_dev{affiliation = 'none'}
+                          when Node_Access_Model == 'presence' ->
+                            case
+                                is_contact_subscribed_to_node_owners(Host,
+                                    Entity, Node_Owners)
+                            of
+                                false ->
+                                    {error, 'forbidden'};
+                                _Node_Owner ->
+                                    ok
+                            end;
+                        #pubsub_state_dev{affiliation = 'none'}
+                          when Node_Access_Model == 'roster' ->
+                            case
+                                is_contact_in_allowed_roster_groups(Entity,
+                                    _Rosters_Groups_Allowed =
+                                        get_value(Node_Options,
+                                            'roster_groups_allowed', []))
+                            of
+                                false ->
+                                    {error, 'forbidden'};
+                                _ ->
+                                    ok
+                            end;
+                        _ ->
+                            {error, 'forbidden'}
+                        
+                    end
+            end
+    end.
+
+%-- Get_Configure_Subscription --%
+-spec(get_configure_subscription/6 ::
+(
+  Host            :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host     :: exmpp_pubsub:host(),
+  Entity          :: xmpp_jid:usr_bare(),
+  Plugin          :: exmpp_pubsub:plugin(),
+  Pubsub_Features :: exmpp_pubsub:pubsub_features(),
+  Parameters      :: {NodeId   :: undefined | exmpp_pubsub:nodeId(),
+                      SubId    :: undefined | exmpp_pubsub:subId(),
+                      Resource :: undefined
+                                | xmpp_jid:resource_jid()
+                                | {'caps', xmpp_jid:resource_jid()}
+                     })
+    -> {result,
+        Subscription :: exmpp_pubsub:subscription_subscribed()
+                      | exmpp_pubsub:subscription_unconfigured()}
+    %%%
+     | {error, 'item-not-found'}
+     | {error, 'unexpected-request', 'not-subscribed'}
+     | {error, 'forbidden'}
+     %
+     | {error, 'unexpected-request', 'not-subscribed'}
+     | {error, 'bad-request',        'subid-required'}
+     | {error, 'forbidden'}
+     | {error, 'not-acceptable',     'invalid-subid'}
+).
+
+get_configure_subscription(_Host, _Pubsub_Host, _Entity, _Plugin,
+  _Pubsub_Features, {undefined = _NodeId, _SubId, _Resource}) ->
+    {error, 'item-not-found'};
+%%
+get_configure_subscription(_Host, Pubsub_Host, Entity, Plugin,
+  Pubsub_Features, {NodeId, SubId, Resource}) ->
+    case pubsub_db_mnesia:read_node('dev', Pubsub_Host, NodeId) of
+        undefined ->
+            {error, 'item-not-found'};
+        #pubsub_node_dev{idx = NodeIdx, owners = Node_Owners, options = Node_Options} ->
+            case pubsub_db_mnesia:read_state('dev', Entity, NodeIdx) of
+                undefined ->
+                    {error, 'unexpected-request', 'not-subscribed'};
+                #pubsub_state_dev{affiliation = Affiliation}
+                  when   Affiliation == 'publish-only'
+                  orelse Affiliation == 'outcast' ->
+                    {error, 'forbidden'};
+                #pubsub_state_dev{subscriptions = []} ->
+                    {error, 'unexpected-request', 'not-subscribed'};
+                #pubsub_state_dev{subscriptions = Subscriptions} ->
+                    case filter_subscription(Subscriptions, SubId, Resource) of
+                        {ok, Subscription} -> {result, Subscription};
+                        Error              -> Error
+                    end
+            end
+    end.
+
+-spec(filter_subscription/3 ::
+(
+  Subscriptions :: exmpp_pubsub:subscriptions(),
+  SubId         :: undefined | exmpp_pubsub:subId(),
+  Resource      :: undefined
+                 | xmpp_jid:resource_jid()
+                 | {'caps', xmpp_jid:resource_jid()})
+    -> {ok,
+        Subscription :: exmpp_pubsub:subscription_subscribed()
+                      | exmpp_pubsub:subscription_unconfigured()}
+    %%%
+     | {error, 'unexpected-request', 'not-subscribed'}
+     | {error, 'bad-request',        'subid-required'}
+     | {error, 'forbidden'}
+     | {error, 'not-acceptable',     'invalid-subid'}
+).
+
+filter_subscription(Subscriptions, undefined = _SubId, Resource) ->
+    case lists:keytake(Resource, 3, Subscriptions) of
+        {value, {Subscription_State, SubId, Resource, Subscription_Options},
+         _Subscriptions} ->
+            case lists:keymember(Resource, 3, _Subscriptions) of
+                false
+                  when Subscription_State == 'pending' ->
+                    {error, 'forbidden'};
+                false ->
+                    {ok,
+                     {Subscription_State, SubId, Resource, Subscription_Options}};
+                true ->
+                    {error, 'bad-request', 'subid-required'}
+            end;
+         false ->
+            {error, 'unexpected-request', 'not-subscribed'}
+    end;
+%%
+filter_subscription(Subscriptions, SubId, Resource) ->
+    case lists:keyfind(SubId, 2, Subscriptions) of
+        %%
+        {'pending', _, Resource, _} ->
+            {error, 'forbidden'};
+        %%
+        {Subscription_State, SubId, Resource, Subscription_Options} ->
+            {ok, {Subscription_State, SubId, Resource, Subscription_Options}};
+        %%
+        {_, SubId, _, _} ->
+            {error, 'unexpected-request', 'not-subscribed'};
+        false ->
+            case lists:keyfind(Resource, 3, Subscriptions) of
+                {'pending', _, Resource, _} ->
+                    {error, 'forbidden'};
+                {_, _, Resource, _} ->
+                    {error, 'not-acceptable', 'invalid-subid'};
+                _ ->
+                    {error, 'unexpected-request', 'not-subscribed'}
+            end
+    end.
+
+%-- Get_Configure_Node --%
+-spec(get_configure_node/4 ::
+(
+  Host        :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host :: exmpp_pubsub:host(),
+  Entity      :: xmpp_jid:usr_bare(),
+  Parameters  :: {NodeId :: undefined | exmpp_pubsub:nodeId()})
+    -> {result, Node_Options :: pubsub_options:options_node()}
+    %%%
+     | {error, 'bad-request', 'nodeid-required'}
+     | {error, 'item-not-found'}
+     | {error, 'forbidden'}
+).
+
+get_configure_node(_Host, _Pubsub_Host, _Entity, {undefined = _NodeId}) ->
+    {error, 'bad-request', 'nodeid-required'};
+%%
+get_configure_node(_Host, Pubsub_Host, Entity, {NodeId}) ->
+    case pubsub_db_mnesia:read_node('dev', Pubsub_Host, NodeId) of
+        undefined ->
+            {error, 'item-not-found'};
+        #pubsub_node_dev{owners = Node_Owners, options = Node_Options} ->
+            case lists:member(Entity, Node_Owners) of
+                true  -> {result, Node_Options};
+                false -> {error, 'forbidden'}
+            end
+    end.
diff --git a/src/mod_pubsub_ng/pubsub_db_mnesia.erl b/src/mod_pubsub_ng/pubsub_db_mnesia.erl
new file mode 100644
index 000000000..ac41c36a0
--- /dev/null
+++ b/src/mod_pubsub_ng/pubsub_db_mnesia.erl
@@ -0,0 +1,2129 @@
+%%% ====================================================================
+%%% ``The contents of this file are subject to the Erlang Public License,
+%%% Version 1.1, (the "License"); you may not use this file except in
+%%% compliance with the License. You should have received a copy of the
+%%% Erlang Public License along with this software. If not, it can be
+%%% retrieved via the world wide web at http:%%www.erlang.org/.
+%%% 
+%%% Software distributed under the License is distributed on an "AS IS"
+%%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%%% the License for the specific language governing rights and limitations
+%%% under the License.
+%%% 
+%%% The Initial Developer of the Original Code is ProcessOne.
+%%% Portions created by ProcessOne are Copyright 2006-2011, ProcessOne
+%%% All Rights Reserved.''
+%%% This software is copyright 2006-2011, ProcessOne.
+%%%
+%%% @copyright 2006-2011 ProcessOne
+%%% @author Karim Gemayel <karim.gemayel@process-one.net>
+%%%   [http:%%www.process-one.net/]
+%%% @version {@vsn}, {@date} {@time}
+%%% @end
+%%% ====================================================================
+
+%%% @headerfile "pubsub_dev.hrl"
+
+-module(pubsub_db_mnesia).
+-author('karim.gemayel@process-one.net').
+
+-compile(export_all).
+
+-include("pubsub_dev.hrl").
+-include("pubsub_api.hrl").
+
+
+-import(pubsub_tools,
+[
+  get_option/2,
+  get_option/3,
+  get_value/2,
+  get_value/3,
+  set_value/3,
+  %%
+  check_access_model/3,
+  check_access_model/7,
+  check_publish_model/3,
+  is_contact_subscribed_to_node_owners/3,
+  is_contact_in_allowed_roster_groups/2,
+  has_subscriptions/1
+]).
+
+
+-export_type([
+  suffix/0,
+  table/0
+]).
+
+-type(suffix() :: undefined | atom()).
+-type(table() :: atom()).
+
+
+%%
+-spec(init/1 ::
+(
+  Suffix :: undefined | atom())
+    -> 'ok'
+).
+
+init(Suffix) ->
+    create_table_pubsub_node(Suffix),
+    create_table_pubsub_state(Suffix),
+    create_table_pubsub_item(Suffix),
+    create_table_pubsub_last_item(Suffix),
+    create_table_pubsub_subscription_pending(Suffix),
+    pubsub_index_dev:init(Suffix),
+    pubsub_groups:create_table_pubsub_groups(Suffix).
+
+%%
+-spec(table/2 ::
+(
+  Base_Table :: atom(),
+  Suffix     :: undefined | atom())
+    -> Table :: atom()
+).
+
+table(Base_Table, undefined = _Suffix) ->
+    _Table = Base_Table;
+table(Base_Table, Suffix) ->
+    _Table = list_to_atom(atom_to_list(Base_Table) ++ "_" ++ atom_to_list(Suffix)).
+
+
+%%
+create_table_pubsub_node(Suffix) ->
+    mnesia:create_table(table('pubsub_node', Suffix),
+        [{type, set},
+         {disc_copies, [node()]},
+         {record_name, pubsub_node_dev},
+         {attributes, record_info(fields, pubsub_node_dev)}]),
+    mnesia:add_table_index(pubsub_node_dev, idx).
+
+create_table_pubsub_state(Suffix) ->
+    mnesia:create_table(table('pubsub_state', Suffix),
+        [{type, set},
+         {disc_copies, [node()]},
+         {record_name, pubsub_state_dev},
+         {attributes, record_info(fields, pubsub_state_dev)}]),
+    mnesia:add_table_index(pubsub_state_dev, nodeidx).
+
+create_table_pubsub_item(Suffix) ->
+    mnesia:create_table(table('pubsub_item', Suffix),
+        [{type, set},
+         {disc_copies, [node()]},
+         {record_name, pubsub_item_dev},
+         {attributes, record_info(fields, pubsub_item_dev)}]),
+    mnesia:add_table_index(pubsub_item_dev, nodeidx).
+
+create_table_pubsub_last_item(Suffix) ->
+    mnesia:create_table(table('pubsub_last_item', Suffix),
+        [{type, set},
+         {disc_copies, [node()]},
+         {record_name, pubsub_last_item_dev},
+         {attributes, record_info(fields, pubsub_last_item_dev)}]).
+
+create_table_pubsub_subscription_pending(Suffix) ->
+    mnesia:create_table(table('pubsub_subscription_pending', Suffix),
+        [{type, set},
+         {disc_copies, [node()]},
+         {record_name, pubsub_subscription_pending},
+         {attributes, record_info(fields, pubsub_subscription_pending)}]),
+    mnesia:add_table_index(pubsub_subscription_pending, nodeidx).
+
+%%
+transaction(Module, Function, Arguments) ->
+    case mnesia:transaction(fun() -> apply(Module, Function, Arguments) end) of
+        {atomic, Result} ->
+            Result;
+        {aborted, Reason} ->
+            ?INFO_MSG("DB TRANSACTION ERROR ~p", [Reason]),
+            {error, 'internal-server-error'}
+    end.
+
+%%
+-spec(read_item/3 ::
+(
+  Suffix  :: atom(),
+  NodeIdx :: exmpp_pubsub:nodeIdx(),
+  ItemId  :: exmpp_pubsub:itemId())
+    -> Pubsub_Item :: undefined | mod_pubsub_dev:pubsub_item()
+).
+
+read_item(Suffix, NodeIdx, ItemId) ->
+    _Pubsub_Item = case
+        mnesia:read({_Table = table('pubsub_item', Suffix), {ItemId, NodeIdx}})
+    of
+        [Pubsub_Item] -> Pubsub_Item;
+        []            -> undefined
+    end.
+
+%%
+-spec(read_node/3 ::
+(
+  Suffix      :: atom(),
+  Pubsub_Host :: exmpp_pubsub:host(),
+  NodeId      :: exmpp_pubsub:nodeId())
+    -> Pubsub_Node :: undefined | mod_pubsub_dev:pubsub_node()
+).
+
+read_node(Suffix, Pubsub_Host, NodeId) ->
+    _Pubsub_Node = case
+        mnesia:read({_Table = table('pubsub_node', Suffix),
+            {Pubsub_Host, NodeId}})
+    of
+        [Pubsub_Node] -> Pubsub_Node;
+        []            -> undefined
+    end.
+
+%%
+-spec(read_state/3 ::
+(
+  Suffix  :: atom(),
+  Entity  :: xmpp_jid:usr_entity(),
+  NodeIdx :: exmpp_pubsub:nodeIdx())
+    -> Pubsub_State :: undefined | mod_pubsub_dev:pubsub_state()
+).
+
+read_state(Suffix, {U,S,_R} = _Entity, NodeIdx) ->
+    _Pubsub_State = case
+        mnesia:read({_Table = table('pubsub_state', Suffix),
+            {{U,S,undefined}, NodeIdx}})
+    of
+        [Pubsub_State] -> Pubsub_State;
+        []             -> undefined
+    end.
+
+%%
+-spec(index_read_node/2 ::
+(
+  Suffix  :: atom(),
+  NodeIdx :: exmpp_pubsub:nodeIdx())
+    -> Pubsub_Nodes::[Pubsub_Node::mod_pubsub_dev:pubsub_node()]
+).
+
+index_read_node(Suffix, NodeIdx) ->
+    _Pubsub_Nodes = mnesia:index_read(_Table = table('pubsub_node', Suffix),
+        NodeIdx, idx).
+
+%%
+-spec(index_read_state/2 ::
+(
+  Suffix  :: atom(),
+  NodeIdx :: exmpp_pubsub:nodeIdx())
+    -> Pubsub_States::[Pubsub_State::mod_pubsub_dev:pubsub_state()]
+).
+
+index_read_state(Suffix, NodeIdx) ->
+    _Pubsub_States = mnesia:index_read(_Table = table('pubsub_state', Suffix),
+        NodeIdx, nodeidx).
+
+
+%-- Create_Node --%
+-spec(create_node/7 ::
+(
+  Suffix          :: atom(),
+  Pubsub_Host     :: exmpp_pubsub:host(),
+  Entity          :: xmpp_jid:usr_entity(),
+  NodeId          :: exmpp_pubsub:nodeId(),
+  Level           :: exmpp_pubsub:level(),
+  Node_Options    :: pubsub_options:options_node(),
+  Pubsub_Features :: exmpp_pubsub:pubsub_features())
+    -> Subscription :: undefined | exmpp_pubsub:subscription_subscribed()
+).
+
+create_node(Suffix, Pubsub_Host, {U,S,R} = _Entity, NodeId, Level, Node_Options,
+  Pubsub_Features) ->
+    %% Create Pubsub_Node
+    mnesia:write(table('pubsub_node', Suffix),
+        #pubsub_node_dev{
+            id       = {Pubsub_Host, NodeId},
+            idx      = NodeIdx = pubsub_index_dev:new(Suffix, 'node'),
+            level    = Level,
+            creation = {_DateTime = now(), _Creator = {U,S,R}},
+            owners   = [{U,S,undefined}],
+            options  = Node_Options
+        },
+        write),
+    _Subscription = case
+        lists:member(<<"auto-subscribe">>, Pubsub_Features)
+            andalso
+        get_value(Node_Options, 'subscribe', false)
+    of
+        true ->
+            mnesia:write(table('pubsub_state', Suffix),
+                #pubsub_state_dev{
+                    id            = {{U,S,undefined}, NodeIdx},
+                    nodeidx       = NodeIdx,
+                    affiliation   = 'owner',
+                    subscriptions = [Subscription = {
+                        _Subscription_State = 'subscribed',
+                        _SubId = exmpp_pubsub:subId(),
+                        _Resource = undefined,
+                        _Subscription_Options = []
+                    }]
+                },
+                write),
+            Subscription;
+        false ->
+            mnesia:write(table('pubsub_state', Suffix),
+                #pubsub_state_dev{
+                    id          = {{U,S,undefined}, NodeIdx},
+                    nodeidx     = NodeIdx,
+                    affiliation = 'owner'
+                },
+                write),
+            undefined
+    end.
+
+%-- Purge_Node --%
+%% TODO : purge Pubsub_Purge_Offline
+%% TODO : purge Pubsub_Expiry_Item
+-spec(purge_node/2 ::
+(
+  Suffix      :: atom(),
+  Pubsub_Node :: mod_pubsub_dev:pubsub_node())
+    -> Recipients :: undefined | [Entity::xmpp_jid:usr_bare()]
+).
+
+purge_node(Suffix, Pubsub_Node) ->
+    %% Update Pubsub_Node
+    mnesia:write(table('pubsub_node', Suffix),
+        Pubsub_Node#pubsub_node_dev{itemids = []}, write),
+    %% Delete Pubsub_Last_Item
+    mnesia:delete(table('pubsub_last_item', Suffix),
+        NodeIdx = Pubsub_Node#pubsub_node_dev.idx, write),
+    %%
+    Table_Pubsub_State = table('pubsub_state', Suffix),
+    Table_Pubsub_Item = table('pubsub_item', Suffix),
+    _Recipients = case
+        get_value(Pubsub_Node#pubsub_node_dev.options, 'notify_retract', false)
+    of
+        true ->
+            %% Delete Pubsub_Items
+            lists:foreach(fun
+                (Pubsub_Item) ->
+                    mnesia:delete_object(Table_Pubsub_Item, Pubsub_Item, write)
+                %
+            end, _Pubsub_Items = mnesia:index_read(Table_Pubsub_Item, NodeIdx,
+                     nodeidx)),
+            %% Update Pubsub_States
+            _Subscribers = lists:foldl(fun
+                %%
+                (Pubsub_State, Subscribers)
+                  when (Pubsub_State#pubsub_state_dev.affiliation == 'owner'
+                            orelse
+                        Pubsub_State#pubsub_state_dev.affiliation == 'outcast'
+                            orelse
+                        Pubsub_State#pubsub_state_dev.affiliation == 'publish-only')
+                  andalso Pubsub_State#pubsub_state_dev.itemids =/= [] ->
+                    mnesia:write(Table_Pubsub_State,
+                        Pubsub_State#pubsub_state_dev{itemids = []},
+                        write),
+                    Subscribers;
+                %%
+                (#pubsub_state_dev{id = {Entity, _NodeIdx}} = Pubsub_State,
+                 Subscribers)
+                  when    Pubsub_State#pubsub_state_dev.affiliation == 'publisher'
+                  andalso Pubsub_State#pubsub_state_dev.itemids     =/= [] ->
+                    mnesia:write(Table_Pubsub_State,
+                        Pubsub_State#pubsub_state_dev{itemids = []}, write),
+                    case Pubsub_State#pubsub_state_dev.subscriptions of
+                        [] = _Subscriptions ->
+                            Subscribers;
+                        _Subscriptions ->
+                            [_Subscriber = Entity | Subscribers]
+                    end;
+                %%
+                (#pubsub_state_dev{id = {Entity, _NodeIdx}} = Pubsub_State,
+                 Subscribers)
+                  when    Pubsub_State#pubsub_state_dev.affiliation   == 'publisher'
+                  andalso Pubsub_State#pubsub_state_dev.subscriptions =/= [] ->
+                    [_Subscriber = Entity | Subscribers];
+                %%
+                (#pubsub_state_dev{id = {Entity, _NodeIdx}} = Pubsub_State,
+                 Subscribers)
+                  when    Pubsub_State#pubsub_state_dev.affiliation == 'member'
+                  andalso Pubsub_State#pubsub_state_dev.itemids     =/= [] ->
+                    mnesia:write(Table_Pubsub_State,
+                        Pubsub_State#pubsub_state_dev{itemids = []}, write),
+                    case
+                        (Pubsub_State#pubsub_state_dev.subscriptions == []
+                             orelse
+                         has_subscriptions(
+                             Pubsub_State#pubsub_state_dev.subscriptions))
+                    of
+                        true  -> [_Subscriber = Entity | Subscribers];
+                        false -> Subscribers
+                    end;
+                %%
+                (#pubsub_state_dev{id = {Entity, _NodeIdx}} = Pubsub_State,
+                 Subscribers)
+                  when Pubsub_State#pubsub_state_dev.affiliation == 'member'->
+                    case
+                        (Pubsub_State#pubsub_state_dev.subscriptions == []
+                             orelse
+                         has_subscriptions(
+                             Pubsub_State#pubsub_state_dev.subscriptions))
+                    of
+                        true  -> [_Subscriber = Entity | Subscribers];
+                        false -> Subscribers
+                    end;
+                %%
+                (_Pubsub_State, Subscribers) ->
+                    Subscribers
+                %
+            end,
+                [],
+                    _Pubsub_States = mnesia:index_read(Table_Pubsub_State,
+                        NodeIdx, nodeidx));
+        false ->
+            %% Update Pubsub_States
+            lists:foreach(fun
+                (_Items_Owner = Entity) ->
+                    case
+                        mnesia:read(Table_Pubsub_State, {Entity, NodeIdx},
+                            write)
+                    of
+                        [Pubsub_State]
+                          when Pubsub_State#pubsub_state_dev.itemids =/= [] ->
+                            mnesia:write(Table_Pubsub_State,
+                                Pubsub_State#pubsub_state_dev{itemids = []},
+                                    write);
+                        _Pubsub_State ->
+                            ok
+                    end
+            end,
+                _Items_Owners = lists:foldl(fun
+                    %% Delete Pubsub_Items
+                    (Pubsub_Item, Items_Owners) ->
+                        mnesia:delete_object(Table_Pubsub_Item, Pubsub_Item,
+                            write),
+                        lists:usort(lists:append(Items_Owners,
+                            Pubsub_Item#pubsub_item_dev.owners))
+                end, [],
+                    _Pubsub_Items = mnesia:index_read(Table_Pubsub_Item, NodeIdx,
+                        nodeidx))
+            ),
+            _Subscribers = undefined
+    end.
+
+%-- Delete_Node --%
+-spec(delete_node/2 ::
+(
+  Suffix      :: atom(),
+  Pubsub_Node :: mod_pubsub_dev:pubsub_node())
+    -> Recipients :: undefined | [Entity::xmpp_jid:usr_bare()]
+).
+
+delete_node(Suffix, Pubsub_Node) ->
+    %% Delete Pubsub_Node
+    mnesia:delete_object(table('pubsub_node', Suffix), Pubsub_Node, write),
+    pubsub_index_dev:free(Suffix, 'node',
+        NodeIdx = Pubsub_Node#pubsub_node_dev.idx),
+    %% Delete Pubsub_Last_Item
+    mnesia:delete(table('pubsub_last_item', Suffix), NodeIdx, write),
+    %% Delete Pubsub_Items
+    Table_Pubsub_Item = table('pubsub_item', Suffix),
+    lists:foreach(fun
+        (Pubsub_Item) ->
+            mnesia:delete_object(Table_Pubsub_Item, Pubsub_Item, write)
+        %
+    end,
+        _Pubsub_Items = mnesia:index_read(Table_Pubsub_Item, NodeIdx,
+            nodeidx)),
+    %% Delete Pubsub_States
+    Table_Pubsub_State = table('pubsub_state', Suffix),
+    _Recipients = case
+        get_value(Pubsub_Node#pubsub_node_dev.options, 'notify_delete', false)
+    of
+        true ->
+            _Subscribers = lists:foldl(fun
+                (#pubsub_state_dev{id = {Entity, _NodeIdx}} = Pubsub_State,
+                 Subscribers) ->
+                    mnesia:delete_object(Table_Pubsub_State, Pubsub_State,
+                        write),
+                    case
+                        {Pubsub_State#pubsub_state_dev.affiliation,
+                         Pubsub_State#pubsub_state_dev.subscriptions}
+                    of
+                        %%
+                        {'publisher' = _Affiliation, Subscriptions}
+                          when Subscriptions =/= [] ->
+                            [_Subscriber = Entity | Subscribers];
+                        %%
+                        {'member' = _Affiliation, _Subscriptions} ->
+                            case
+                                (_Subscriptions == []
+                                     orelse
+                                 has_subscriptions(_Subscriptions))
+                            of
+                                true ->
+                                    [_Subscriber = Entity | Subscribers];
+                                false ->
+                                    Subscribers
+                            end;
+                        %%
+                        {_Affiliation, _Subscriptions} ->
+                            Subscribers
+                    end
+                %
+            end, [],
+                _Pubsub_States = mnesia:index_read(Table_Pubsub_State, NodeIdx,
+                    nodeidx));
+        false ->
+            lists:foreach(fun
+                (Pubsub_State) ->
+                    mnesia:delete_object(Table_Pubsub_State, Pubsub_State,
+                        write)
+            end,
+                _Pubsub_States = mnesia:index_read(Table_Pubsub_State, NodeIdx,
+                    nodeidx)),
+            _Subscribers = undefined
+    end.
+
+%-- Get_Entity_Subscriptions --%
+-spec(get_entity_subscriptions/4 ::
+(
+  Suffix      :: atom(),
+  Pubsub_Host :: exmpp_pubsub:host(),
+  Entity      :: xmpp_jid:usr_entity(),
+  NodeId      :: undefined | exmpp_pubsub:nodeId())
+    -> Entity_Subscriptions :: [{
+           NodeId        :: exmpp_pubsub:nodeId(),
+           Subscriptions :: exmpp_pubsub:subscriptions()
+       }]
+).
+
+get_entity_subscriptions(Suffix, Pubsub_Host, {U,S,_R} = _Entity,
+  undefined = _NodeId) ->
+    Table_Pubsub_Node = table('pubsub_node', Suffix),
+    _Entity_Subscriptions = lists:foldl(fun
+        ([NodeIdx, Subscriptions], Entity_Subscriptions) ->
+            case mnesia:index_read(Table_Pubsub_Node, NodeIdx, idx) of
+                %% IMPORTANT : Pubsub_Host must be used in the matching,
+                %% else it'd return all NodeIds subscriptions (in case of VHosts)
+                %% and not only the ones from to the current Pubsub_Host
+                [#pubsub_node_dev{id = {Pubsub_Host, NodeId}}] ->
+                    [{NodeId, Subscriptions} | Entity_Subscriptions];
+                _Pubsub_Node ->
+                    Entity_Subscriptions
+            end
+    end, [],
+        mnesia:select(table('pubsub_state', Suffix),
+            [{#pubsub_state_dev{
+                  id            = {{U,S,undefined}, '$1'},
+                  subscriptions = '$2',
+                  _             = '_'},
+            [{'=/=', '$2', []}],
+            ['$$']}]));
+%%
+get_entity_subscriptions(Suffix, Pubsub_Host, {U,S,_R} = _Entity, NodeId) ->
+    _Entity_Subscriptions = case
+        mnesia:read(table('pubsub_node', Suffix), {Pubsub_Host, NodeId}, read)
+    of
+        [] ->
+            [];
+        [#pubsub_node_dev{idx = NodeIdx}] ->
+            case
+                mnesia:read(table('pubsub_state', Suffix),
+                    {{U,S,undefined}, NodeIdx}, read)
+            of
+                [#pubsub_state_dev{subscriptions = Subscriptions}]
+                  when Subscriptions =/= [] ->
+                    [{NodeId, Subscriptions}];
+                _Pubsub_State ->
+                    []
+            end
+    end.
+
+%-- Get_Entity_Affiliations --%
+-spec(get_entity_affiliations/4 ::
+(
+  Suffix      :: atom(),
+  Pubsub_Host :: exmpp_pubsub:host(),
+  Entity      :: xmpp_jid:usr_bare(),
+  NodeId      :: undefined | exmpp_pubsub:nodeId())
+    -> Entity_Affiliations :: [Entity_Affiliation :: {
+           NodeId      :: exmpp_pubsub:nodeId(),
+           Affiliation :: exmpp_pubsub:affiliation()
+       }]
+).
+
+get_entity_affiliations(Suffix, Pubsub_Host, {U,S,_R} = _Entity,
+  undefined = _NodeId) ->
+    Table_Pubsub_Node = table('pubsub_node', Suffix),
+    _Entity_Affiliations = lists:foldl(fun
+        ([NodeIdx, Affiliation], Entity_Affiliations) ->
+            case mnesia:index_read(Table_Pubsub_Node, NodeIdx, idx) of
+                %% IMPORTANT : Pubsub_Host must be used in the matching,
+                %% else it'd return all NodeIds affiliations (in case of VHosts)
+                %% and not only the ones from to the current Pubsub_Host
+                [#pubsub_node_dev{id = {Pubsub_Host, NodeId}}] ->
+                    [{NodeId, Affiliation} | Entity_Affiliations];
+                _Pubsub_Node ->
+                    Entity_Affiliations
+            end
+    end, [],
+        mnesia:select(table('pubsub_state', Suffix),
+            [{#pubsub_state_dev{
+                  id          = {{U,S,undefined}, '$1'},
+                  affiliation = '$2',
+                  _           = '_'},
+             [],
+             ['$$']}],
+             read)
+        );
+%%
+get_entity_affiliations(Suffix, Pubsub_Host, {U,S,_R} = _Entity, NodeId) ->
+    _Entity_Affiliations = case
+        mnesia:read(table('pubsub_node', Suffix), {Pubsub_Host, NodeId}, read)
+    of
+        [] ->
+            [];
+        [#pubsub_node_dev{idx = NodeIdx}] ->
+            case
+                mnesia:read(table('pubsub_state', Suffix),
+                    {{U,S,undefined}, NodeIdx})
+            of
+                [#pubsub_state_dev{affiliation = Affiliation}] ->
+                    [{NodeId, Affiliation}];
+                _Pubsub_State ->
+                    []
+            end
+    end.
+
+%-- Publish_Item --%
+-spec(publish_item1/9 ::
+(
+  Suffix          :: atom(),
+  Pubsub_Host     :: exmpp_pubsub:host(),
+  Entity          :: xmpp_jid:usr_entity(),
+  NodeId          :: undefined | exmpp_pubsub:nodeId(),
+  Level           :: exmpp_pubsub:level(),
+  ItemId          :: undefined | exmpp_pubsub:itemId(),
+  Payload         :: [Xmlel::#xmlel{}] | exmpp_pubsub:payload(),
+  Options         :: {Node_Options :: pubsub_options:options_node(),
+                      Item_Options :: [] | pubsub_options:options_item()},
+  Pubsub_Features :: exmpp_pubsub:pubsub_features())
+    -> {ItemId             :: exmpp_pubsub:itemId(),
+        Pubsub_State@Owner :: mod_pubsub_dev:pubsub_state_owner()}
+).
+
+publish_item1(Suffix, Pubsub_Host, Entity, NodeId, Level, ItemId,
+  [Payload], Options, Pubsub_Features) ->
+    publish_item1(Suffix, Pubsub_Host, Entity, NodeId, Level, ItemId, Payload,
+        Options, Pubsub_Features);
+
+publish_item1(Suffix, Pubsub_Host, Entity, NodeId, Level, undefined = _ItemId,
+  Payload, Options, Pubsub_Features) ->
+    publish_item1(Suffix, Pubsub_Host, Entity, NodeId, Level,
+        exmpp_pubsub:itemId(), Payload, Options, Pubsub_Features);
+%%
+publish_item1(Suffix, Pubsub_Host, {U,S,R} = _Entity, NodeId, Level, ItemId,
+  Payload, {Node_Options, Item_Options} = Options, Pubsub_Features) ->
+    NodeIdx = pubsub_index_dev:new(Suffix, 'node'),
+    DateTime = now(),
+    Write_Item = get_value(Options, 'persist_items', false) andalso
+        (get_value(Node_Options, 'max_items', 0) > 0),
+    %% Create Pubsub_Node
+    mnesia:write(table('pubsub_node', Suffix),
+        #pubsub_node_dev{
+            id       = {Pubsub_Host, NodeId},
+            idx      = NodeIdx,
+            creation = {DateTime, _Creator = {U,S,R}},
+            level    = Level,
+            owners   = [{U,S,undefined}],
+            itemids  = case Write_Item of
+                true  -> [ItemId];
+                false -> []
+            end,
+            options  = Node_Options
+        },
+        write),
+    %% Create Pubsub_Item
+    case Write_Item of
+        false ->
+            ok;
+        true ->
+            mnesia:write(table('pubsub_item', Suffix),
+                #pubsub_item_dev{
+                    id       = {ItemId, NodeIdx},
+                    nodeidx  = NodeIdx,
+                    owners   = [{U,S,undefined}],
+                    creation = {DateTime, _Creator = {U,S,R}},
+                    payload  = Payload,
+                    options  = Item_Options
+                },
+                write),
+            %%TODO : Register pubsub#item_expire
+            case get_value(Options, 'item_expire', undefined) of
+                undefined ->
+                    ko;
+                Delay ->
+                    ok
+            end
+    end,
+    %% Create Pubsub_Last_Item
+    case get_value(Options, 'send_last_published_item', 'never') of
+        'never' ->
+            ok;
+        _Send_Last_Published_Item ->
+            mnesia:write(table('pubsub_last_item', Suffix),
+                #pubsub_last_item_dev{
+                    nodeidx  = NodeIdx,
+                    id       = ItemId,
+                    owners   = [{U,S,undefined}],
+                    creation = {DateTime, _Creator = {U,S,R}},
+                    payload  = Payload,
+                    options  = Item_Options
+                },
+                write)
+    end,
+    %% Create Pubsub_State
+    mnesia:write(table('pubsub_state', Suffix),
+        Pubsub_State = #pubsub_state_dev{
+            id            = {{U,S,undefined}, NodeIdx},
+            nodeidx       = NodeIdx,
+            itemids       = case Write_Item of
+                true  -> [ItemId];
+                false -> []
+            end,
+            affiliation   = 'owner',
+            subscriptions = case
+                lists:member(<<"auto-subscribe">>, Pubsub_Features)
+                    andalso
+                get_value(Node_Options, 'subscribe', false)
+            of
+                true  ->
+                    [{_Subscription_State = 'subscribed',
+                      _SubId = exmpp_pubsub:subId(),
+                      _Resource = undefined,
+                      _Subscription_Options = []}];
+                false ->
+                    []
+            end
+        },
+        write),
+    {ItemId, Pubsub_State}.
+
+%%
+-spec(publish_item2/9 ::
+(
+  Suffix          :: atom(),
+  Pubsub_Host     :: exmpp_pubsub:host(),
+  Entity          :: xmpp_jid:usr_entity(),
+  Pubsub_State    :: undefined | mod_pubsub_dev:pubsub_state(),
+  Pubsub_Node     :: mod_pubsub_dev:pubsub_node(),
+  _               :: undefined | exmpp_pubsub:itemId() | mod_pubsub_dev:pubsub_item(),
+  Payload         :: [Xmlel::#xmlel{}] | exmpp_pubsub:payload(),
+  Options         :: {Node_Options :: pubsub_options:options_node(),
+                      Item_Options :: [] | pubsub_options:options_item()},
+  Pubsub_Features :: exmpp_pubsub:pubsub_features())
+    -> {ItemId          :: exmpp_pubsub:itemId(),
+        Retracted_Items :: [Retracted_Item::{
+            ItemId       :: exmpp_pubsub:itemId(),
+            Item_Options :: [] | pubsub_options:options_node()
+        }],
+        Pubsub_States   :: [Pubsub_State::mod_pubsub_dev:pubsub_state(),...]}
+).
+
+
+publish_item2(Suffix, Pubsub_Host, Entity, Pubsub_State, Pubsub_Node, Pubsub_Item,
+  [Payload], Item_Options, Pubsub_Features) ->
+    publish_item2(Suffix, Pubsub_Host, Entity, Pubsub_State, Pubsub_Node,
+        Pubsub_Item, Payload, Item_Options, Pubsub_Features);
+%%
+publish_item2(Suffix, Pubsub_Host, {U,S,R} = _Entity, Pubsub_State, Pubsub_Node,
+  #pubsub_item_dev{id = {ItemId, NodeIdx}} = Pubsub_Item, Payload, Item_Options,
+  Pubsub_Features) ->
+    Node_Options = Pubsub_Node#pubsub_node_dev.options,
+    DateTime = now(),
+    Table_Pubsub_State = table('pubsub_state', Suffix),
+    _Retracted_Items = case
+        {get_value(Node_Options, 'persist_items', false),
+         get_value(Node_Options, 'max_items', 0)}
+    of
+        %%
+        {Persist_Items, Max_Items}
+          when   Persist_Items == false
+          orelse Max_Items     == 0 ->
+            case Pubsub_State of
+                undefined ->
+                    mnesia:write(table('pubsub_state', Suffix),
+                        #pubsub_state_dev{
+                            id      = {{U,S,undefined}, NodeIdx},
+                            nodeidx = NodeIdx
+                        },
+                        write),
+                    [];
+                _Pubsub_State ->
+                    []
+            end;
+        %%
+        {true, undefined} ->
+            mnesia:write(table('pubsub_node', Suffix),
+                Pubsub_Node#pubsub_node_dev{
+                    itemids = lists:reverse([ItemId
+                        | lists:reverse(lists:delete(ItemId,
+                                Pubsub_Node#pubsub_node_dev.itemids))])
+                },
+                write),
+            %%
+            mnesia:write(Table_Pubsub_State,
+                case Pubsub_State of
+                    undefined ->
+                        #pubsub_state_dev{
+                            id      = {{U,S,undefined}, NodeIdx},
+                            nodeidx = NodeIdx,
+                            itemids = [ItemId]
+                        };
+                    _ ->
+                        Pubsub_State#pubsub_state_dev{
+                            itemids = [ItemId | lists:delete(ItemId,
+                                Pubsub_State#pubsub_state_dev.itemids)]
+                        }
+                end,
+                write),
+            mnesia:write(table('pubsub_item', Suffix),
+                Pubsub_Item#pubsub_item_dev{
+                    modification = {DateTime, {U,S,R}},
+                    payload      = Payload,
+                    options      = Item_Options,
+                    owners       = [{U,S,undefined} |
+                        lists:delete({U,S,undefined},
+                            Pubsub_Item#pubsub_item_dev.owners)]
+                },
+                write),
+            [];
+        {true, Max_Items} ->
+            {New_ItemIds, Old_ItemIds} = max_items(Max_Items,
+                lists:reverse([ItemId
+                    | lists:reverse(lists:delete(ItemId,
+                          Pubsub_Node#pubsub_node_dev.itemids))])),
+            {Retracted_Items, Publisher_Retracted_ItemIds} =
+                delete_old_items(Suffix,
+                    _Publisher = {U,S,undefined},
+                    NodeIdx,
+                    _Notify_Retract = get_value(Node_Options,
+                        'notify_retract', false),
+                    Old_ItemIds, {[], {[], []}}),
+            %%
+            mnesia:write(table('pubsub_node', Suffix),
+                Pubsub_Node#pubsub_node_dev{
+                    itemids = New_ItemIds
+                },
+                write),
+            mnesia:write(table('pubsub_item', Suffix),
+                Pubsub_Item#pubsub_item_dev{
+                    modification = {DateTime, {U,S,R}},
+                    payload      = Payload,
+                    options      = Item_Options,
+                    owners       = [{U,S,undefined} |
+                        lists:delete({U,S,undefined},
+                            Pubsub_Item#pubsub_item_dev.owners)]
+                },
+                write),
+            mnesia:write(Table_Pubsub_State,
+                case Pubsub_State of
+                    undefined ->
+                        #pubsub_state_dev{
+                            id      = {{U,S,undefined}, NodeIdx},
+                            nodeidx = NodeIdx,
+                            itemids = [ItemId]
+                        };
+                    _ ->
+                        Pubsub_State#pubsub_state_dev{
+                            itemids = [ItemId
+                                | lists:foldl(fun
+                                        (Publisher_Retracted_ItemId,
+                                            Publisher_ItemIds) ->
+                                                lists:delete(
+                                                    Publisher_Retracted_ItemId,
+                                                    Publisher_ItemIds)
+                                    end,
+                                        lists:delete(ItemId,
+                                            Pubsub_State#pubsub_state_dev.itemids),
+                                                Publisher_Retracted_ItemIds)]
+                        }
+                end,
+                write),
+                Retracted_Items
+
+    end,
+    case get_value(Node_Options, 'send_last_published_item', 'never') of
+        'never' ->
+            ok;
+        _Send_Last_Published_Item ->
+            mnesia:write(table('pubsub_last_item', Suffix),
+                #pubsub_last_item_dev{
+                    nodeidx  = NodeIdx,
+                    id       = ItemId,
+                    owners   = [{U,S,undefined}],
+                    creation = {DateTime, _Creator = {U,S,R}},
+                    payload  = Payload,
+                    options  = Item_Options
+                },
+                write)
+    end,
+    {ItemId, _Retracted_Items,
+     _Pubsub_States = mnesia:index_read(Table_Pubsub_State, NodeIdx, nodeidx)};
+%%
+publish_item2(Suffix, Pubsub_Host, {U,S,R} = Entity, Pubsub_State, Pubsub_Node,
+  _ItemId, Payload, Item_Options, Pubsub_Features) ->
+    NodeIdx = Pubsub_Node#pubsub_node_dev.idx,
+    Node_Options = Pubsub_Node#pubsub_node_dev.options,
+    ItemId = case _ItemId of
+        undefined -> exmpp_pubsub:itemId();
+        _         -> _ItemId
+    end,
+    DateTime = now(),
+    Table_Pubsub_State = table('pubsub_state', Suffix),
+    _Retracted_Items = case
+        {get_value(Node_Options, 'persist_items', false),
+         get_value(Node_Options, 'max_items', 0)}
+    of
+        %%
+        {Persist_Items, Max_Items}
+          when   Persist_Items == false
+          orelse Max_Items     == 0 ->
+            case Pubsub_State of
+                undefined ->
+                    mnesia:write(Table_Pubsub_State,
+                        #pubsub_state_dev{
+                            id      = {{U,S,undefined}, NodeIdx},
+                            nodeidx = NodeIdx
+                        },
+                        write),
+                    [];
+                _Pubsub_State ->
+                    []
+            end;
+        %%
+        {true, undefined} ->
+            mnesia:write(table('pubsub_node', Suffix),
+                Pubsub_Node#pubsub_node_dev{
+                    itemids = lists:reverse([ItemId
+                        | lists:reverse(ItemId,
+                              Pubsub_Node#pubsub_node_dev.itemids)])
+                },
+                write),
+            %%
+            mnesia:write(Table_Pubsub_State,
+                case Pubsub_State of
+                    undefined ->
+                        #pubsub_state_dev{
+                            id      = {{U,S,undefined}, NodeIdx},
+                            nodeidx = NodeIdx,
+                            itemids = [ItemId]
+                        };
+                    _ ->
+                        Pubsub_State#pubsub_state_dev{
+                            itemids = [ItemId |
+                                Pubsub_State#pubsub_state_dev.itemids]
+                        }
+                end,
+                write),
+                mnesia:write(table('pubsub_item', Suffix),
+                    #pubsub_item_dev{
+                        id       = {ItemId, NodeIdx},
+                        nodeidx  = NodeIdx,
+                        owners   = [{U,S,undefined}],
+                        creation = {DateTime, {U,S,R}},
+                        payload  = Payload,
+                        options  = Item_Options
+                    },
+                    write),
+                [];
+            {true, Max_Items} ->
+                {New_ItemIds, Old_ItemIds} = max_items(Max_Items,
+                    lists:reverse([ItemId
+                        | lists:reverse(Pubsub_Node#pubsub_node_dev.itemids)])),
+                {Retracted_Items, Publisher_Retracted_ItemIds} =
+                    delete_old_items(Suffix,
+                        _Publisher = {U,S,undefined},
+                        NodeIdx,
+                        _Notify_Retract = get_value(Node_Options,
+                            'notify_retract', false),
+                        Old_ItemIds, {[], {[], []}}),
+                %%
+                mnesia:write(table('pubsub_node', Suffix),
+                    Pubsub_Node#pubsub_node_dev{
+                        itemids = New_ItemIds
+                    },
+                    write),
+                mnesia:write(table('pubsub_item', Suffix),
+                    #pubsub_item_dev{
+                        id       = {ItemId, NodeIdx},
+                        nodeidx  = NodeIdx,
+                        owners   = [{U,S,undefined}],
+                        creation = {DateTime, {U,S,R}},
+                        payload  = Payload,
+                        options  = Item_Options
+                    },
+                    write),
+            %%
+            mnesia:write(Table_Pubsub_State,
+                case Pubsub_State of
+                    undefined ->
+                        #pubsub_state_dev{
+                            id      = {{U,S,undefined}, NodeIdx},
+                            nodeidx = NodeIdx,
+                            itemids = [ItemId]
+                        };
+                    _ ->
+                        Pubsub_State#pubsub_state_dev{
+                            itemids = [ItemId
+                                | lists:foldl(fun
+                                        (Publisher_Retracted_ItemId,
+                                         Publisher_ItemIds) ->
+                                             lists:delete(
+                                                 Publisher_Retracted_ItemId,
+                                                 Publisher_ItemIds)
+                                  end,
+                                      Pubsub_State#pubsub_state_dev.itemids,
+                                          Publisher_Retracted_ItemIds)]
+                        }
+                end,
+                write),
+                Retracted_Items
+
+    end,
+    case get_value(Node_Options, 'send_last_published_item', 'never') of
+        'never' ->
+            ok;
+        _Send_Last_Published_Item ->
+            mnesia:write(table('pubsub_last_item', Suffix),
+                #pubsub_last_item_dev{
+                    nodeidx  = NodeIdx,
+                    id       = ItemId,
+                    owners   = [{U,S,undefined}],
+                    creation = {DateTime, _Creator = {U,S,R}},
+                    payload  = Payload,
+                    options  = Item_Options
+                },
+                write)
+    end,
+    {ItemId, _Retracted_Items,
+     _Pubsub_States = mnesia:index_read(Table_Pubsub_State, NodeIdx, nodeidx)}.
+
+%%
+-spec(max_items/2 ::
+(
+  Max_Items   :: undefined | non_neg_integer(),
+  New_ItemIds :: [ItemId::exmpp_pubsub:itemId()])
+    -> ItemIds :: {New_ItemIds::[ItemId::exmpp_pubsub:itemId()],
+                   Old_ItemIds::[ItemId::exmpp_pubsub:itemId()]}
+).
+
+max_items(undefined = _Max_Items, New_ItemIds) ->
+    _ItemIds = {New_ItemIds, _Old_ItemIds = []};
+max_items(0 = _Max_Items, New_ItemIds) ->
+    _ItemIds = {_New_ItemIds = [], _Old_ItemIds = New_ItemIds};
+max_items(Max_Items, New_ItemIds) ->
+    _ItemIds = case Max_Items >= (Length_Items = length(New_ItemIds)) of
+        true ->
+            {New_ItemIds, _Old_ItemIds = []};
+        false ->
+            diff_items((Length_Items - Max_Items), _Count = 0, {New_ItemIds, []})
+    end.
+
+%%
+-spec(diff_items/3 ::
+(
+  Diff_Items :: pos_integer(),
+  Count      :: non_neg_integer(),
+  ItemIds    :: {New_ItemIds::[ItemId::exmpp_pubsub:itemId()],
+                 Old_ItemIds::[ItemId::exmpp_pubsub:itemId()]})
+    -> ItemIds :: {New_ItemIds::[ItemId::exmpp_pubsub:itemId()],
+                   Old_ItemIds::[ItemId::exmpp_pubsub:itemId()]}
+).
+
+diff_items(Diff_Items, _Count = Diff_Items, ItemIds) ->
+    ItemIds;
+diff_items(Diff_Items, Count, {[ItemId | New_ItemIds], Old_ItemIds}) ->
+    diff_items(Diff_Items, Count + 1, {New_ItemIds, [ItemId | Old_ItemIds]}).
+
+
+%%
+-spec(delete_old_items/6 ::
+(
+  Suffix              :: atom(),
+  Publisher           :: xmpp_jid:usr_bare(),
+  NodeIdx             :: exmpp_pubsub:nodeIdx(),
+  Node_Notify_Retract :: boolean(),
+  ItemIds             :: [ItemId::exmpp_pubsub:itemId()],
+  %%
+  {Retracted_Items :: [Retracted_Item::{
+     ItemId       :: exmpp_pubsub:itemId(),
+     Item_Options :: [] | pubsub_options:options_item()
+   }],
+   %
+   Publishers_Retracted_ItemIds :: {
+       %%
+       Entities_Retracted_ItemIds  :: [Entity_Retracted_ItemIds::{
+           Entity  :: xmpp_jid:usr_bare(),
+           ItemIds :: [ItemId::exmpp_pubsub:itemId()]
+       }],
+       %%
+       Publisher_Retracted_ItemIds :: [ItemId::exmpp_pubsub:itemId()]
+   }
+  })
+    -> {Retracted_Items :: [Retracted_Item::{
+          ItemId       :: exmpp_pubsub:itemId(),
+          Item_Options :: [] | pubsub_options:options_item()
+        }],
+        Publisher_Retracted_ItemIds :: [ItemId::exmpp_pubsub:itemId()]}
+).
+
+delete_old_items(Suffix, _Publisher, NodeIdx, _Notify_Retract, [] = _ItemIds,
+  {Retracted_Items, {Entities_ItemIds, Publisher_ItemIds}}) ->
+    Table_Pubsub_State = table('pubsub_state', Suffix),
+    lists:foreach(fun
+        ({Entity, Entity_ItemIds}) ->
+            case mnesia:read(Table_Pubsub_State, {Entity, NodeIdx}, write) of
+                [Pubsub_State] ->
+                    mnesia:write(Table_Pubsub_State,
+                        Pubsub_State#pubsub_state_dev{
+                            itemids = lists:foldl(fun
+                                (Retracted_ItemId, ItemIds) ->
+                                    lists:delete(Retracted_ItemId, ItemIds)
+                          end,
+                              Pubsub_State#pubsub_state_dev.itemids,
+                                    Entity_ItemIds)
+                        },
+                        write);
+                     [] -> %% shouldn't happen
+                        ok
+            end
+            %
+    end, Entities_ItemIds),
+    {Retracted_Items, Publisher_ItemIds};
+%%
+delete_old_items(Suffix, Publisher, NodeIdx, Notify_Retract, [ItemId | ItemIds],
+  {Retracted_Items, Publishers_ItemIds}) ->
+    Table_Pubsub_Item = table('pubsub_item', Suffix),
+    delete_old_items(Suffix, Publisher, NodeIdx, Notify_Retract, ItemIds,
+        case mnesia:read(Table_Pubsub_Item, {ItemId, NodeIdx}, write) of
+            [Pubsub_Item] ->
+                mnesia:delete_object(Table_Pubsub_Item, Pubsub_Item, write),
+                %% @TODO: Unregister 'pubsub#item_expire'
+                {_Retracted_Items = case
+                     get_value(Pubsub_Item#pubsub_item_dev.options,
+                         'notify_retract', Notify_Retract)
+                 of
+                    true ->
+                        [{ItemId, Pubsub_Item#pubsub_item_dev.options}
+                        | Retracted_Items];
+                    false ->
+                        Retracted_Items
+                 end,
+                 %%
+                 _Publishers_ItemIds = lists:foldl(fun
+                     %%
+                     (Item_Owner, {Entities_ItemIds, Publisher_ItemIds})
+                       when Item_Owner == Publisher ->
+                         {Entities_ItemIds,
+                          [ItemId | Publisher_ItemIds]};
+                     %%
+                     (_Item_Owner = Entity,
+                      {Entities_ItemIds, Publisher_ItemIds}) ->
+                         {_Entities_ItemIds = case
+                              lists:keyfind(Entity, 1, Entities_ItemIds)
+                          of
+                              {_Entity, Entity_ItemIds} ->
+                                  lists:keyreplace(Entity, 1, Entities_ItemIds,
+                                      {Entity, [ItemId | Entity_ItemIds]});
+                            false ->
+                                [{Entity, [ItemId]} | Entities_ItemIds]
+                          end,
+                          Publisher_ItemIds}
+                 end, Publishers_ItemIds, Pubsub_Item#pubsub_item_dev.owners)};
+            [] ->
+                {Retracted_Items, Publishers_ItemIds}
+        end).
+
+
+%-- Retract_Item --%
+-spec(retract_item/5 ::
+(
+  Suffix               :: atom(),
+  Pubsub_Node          :: mod_pubsub_dev:pubsub_node(),
+  Pubsub_State         :: mod_pubsub_dev:pubsub_state_owner()
+                        | mod_pubsub_dev:pubsub_state_member()
+                        | mod_pubsub_dev:pubsub_state_publish_only()
+                        | mod_pubsub_dev:pubsub_state_publisher()
+                        | mod_pubsub_dev:pubsub_state_none(),
+  ItemId               :: exmpp_pubsub:itemId(),
+  Adhoc_Notify_Retract :: undefined | boolean())
+    -> {ok, undefined}
+     %
+     | {ok,
+        Item_Options  :: [] | pubsub_options:options_item(),
+        Pubsub_States :: mod_pubsub_dev:pubsub_states()}
+    %%%
+     | {error, 'forbidden'}
+     | {error, 'item-not-found'}
+).
+
+retract_item(Suffix, Pubsub_Node,
+  #pubsub_state_dev{id = {Entity, NodeIdx}} = Pubsub_State, ItemId,
+  Adhoc_Notify_Retract) ->
+    Table_Pubsub_Item = table('pubsub_item', Suffix),
+    case mnesia:read(Table_Pubsub_Item, {ItemId, NodeIdx}, write) of
+        [Pubsub_Item]
+          when   Pubsub_State#pubsub_state_dev.affiliation == 'owner'
+          orelse Pubsub_State#pubsub_state_dev.affiliation == 'publisher' ->
+            mnesia:delete_object(Table_Pubsub_Item, Pubsub_Item, write),
+            Table_Pubsub_Last_Item = table('pubsub_last_item', Suffix),
+            case mnesia:read(Table_Pubsub_Last_Item, NodeIdx, read) of
+                [Pubsub_Last_Item]
+                  when Pubsub_Last_Item#pubsub_last_item_dev.id == ItemId ->
+                    mnesia:delete_object(Table_Pubsub_Last_Item,
+                        Pubsub_Last_Item, write);
+                _ ->
+                    ok
+            end,
+            Table_Pubsub_State = table('pubsub_state', Suffix),
+            case
+                retract_item(NodeIdx, ItemId, Table_Pubsub_State, Entity,
+                    _Item_Owners = Pubsub_Item#pubsub_item_dev.owners, false)
+            of
+                true ->
+                    mnesia:write(Table_Pubsub_State,
+                        Pubsub_State#pubsub_state_dev{
+                            itemids = lists:delete(ItemId,
+                                Pubsub_State#pubsub_state_dev.itemids)
+                        },
+                        write);
+                false ->
+                    ok
+            end,
+            mnesia:write(table('pubsub_node', Suffix),
+                Pubsub_Node#pubsub_node_dev{
+                    itemids = lists:delete(ItemId,
+                        Pubsub_Node#pubsub_node_dev.itemids)
+                },
+                write),
+            case
+                Adhoc_Notify_Retract == true
+                    orelse
+                get_value(
+                    {Pubsub_Node#pubsub_node_dev.options,
+                     Pubsub_Item#pubsub_item_dev.options},
+                     'notify_retract', false)
+            of
+                true ->
+                    {ok,
+                     _Item_Options = Pubsub_Item#pubsub_item_dev.options,
+                     _Pubsub_States = mnesia:index_read(Table_Pubsub_State, NodeIdx, nodeidx)};
+                false ->
+                    {ok, undefined}
+            end;
+        %%
+        [#pubsub_item_dev{creation = {_DateTime, _Creator = Entity}} = Pubsub_Item] ->
+            mnesia:delete_object(Table_Pubsub_Item, Pubsub_Item, write),
+            Table_Pubsub_Last_Item = table('pubsub_last_item', Suffix),
+            case mnesia:read(Table_Pubsub_Last_Item, NodeIdx, read) of
+                [Pubsub_Last_Item]
+                  when Pubsub_Last_Item#pubsub_last_item_dev.id == ItemId ->
+                    mnesia:delete_object(Table_Pubsub_Last_Item,
+                        Pubsub_Last_Item, write);
+                _ ->
+                    ok
+            end,
+            Table_Pubsub_State = table('pubsub_state', Suffix),
+            case
+                retract_item(NodeIdx, ItemId, Table_Pubsub_State, Entity,
+                    _Item_Owners = Pubsub_Item#pubsub_item_dev.owners, false)
+            of
+                true ->
+                    mnesia:write(Table_Pubsub_State,
+                        Pubsub_State#pubsub_state_dev{
+                            itemids = lists:delete(ItemId,
+                                Pubsub_State#pubsub_state_dev.itemids)
+                        },
+                        write);
+                false ->
+                    ok
+            end,
+            mnesia:write(table('pubsub_node', Suffix),
+                Pubsub_Node#pubsub_node_dev{
+                    itemids = lists:delete(ItemId,
+                        Pubsub_Node#pubsub_node_dev.itemids)
+                },
+                write),
+            case
+                Adhoc_Notify_Retract == true
+                    orelse
+                get_value(
+                    {Pubsub_Node#pubsub_node_dev.options,
+                     Pubsub_Item#pubsub_item_dev.options},
+                     'notify_retract', false)
+            of
+                true ->
+                    {ok,
+                     _Item_Options = Pubsub_Item#pubsub_item_dev.options,
+                     _Pubsub_States = mnesia:index_read(Table_Pubsub_State, NodeIdx, nodeidx)};
+                false ->
+                    {ok, undefined}
+            end;
+        [_Pubsub_Item] ->
+            {error, 'forbidden'};
+        %%
+        [] ->
+            {error, 'item-not-found'}
+    end.
+
+
+%%
+-spec(retract_item/6 ::
+(
+  NodeIdx            :: exmpp_pubsub:nodeIdx(),
+  ItemId             :: exmpp_pubsub:itemId(),
+  Table_Pubsub_State :: atom(),
+  Entity             :: xmpp_jid:usr_bare() | undefined,
+  Item_Owners        :: [Entity::xmpp_jid:usr_bare(),...],
+  Retract_ItemId     :: boolean())
+    -> Retract_ItemId :: boolean()
+).
+
+retract_item(_NodeIdx, _ItemId, _Table_Pubsub_State, _Entity, [] = _Item_Owners,
+  Retract_ItemId) ->
+    Retract_ItemId;
+%%
+retract_item(NodeIdx, ItemId, Table_Pubsub_State, Entity,
+  [_Item_Owner = Entity | Item_Owners], _Retract_ItemId) ->
+    retract_item(NodeIdx, ItemId, Table_Pubsub_State, undefined, Item_Owners,
+        true);
+%%
+retract_item(NodeIdx, ItemId, Table_Pubsub_State, _Entity,
+  [_Item_Owner = Entity | Item_Owners], Retract_ItemId) ->
+    case mnesia:read(Table_Pubsub_State, {Entity, NodeIdx}, write) of
+        [Pubsub_State] ->
+            mnesia:write(Table_Pubsub_State,
+                Pubsub_State#pubsub_state_dev{
+                    itemids = lists:delete(ItemId,
+                        Pubsub_State#pubsub_state_dev.itemids)
+                },
+                write);
+        [] ->
+            ok
+    end,
+    retract_item(NodeIdx, ItemId, Table_Pubsub_State, _Entity, Item_Owners,
+        Retract_ItemId).
+
+%-- Subscribe_Node --%
+-spec(subscribe_node/8 ::
+(
+  Suffix               :: atom(),
+  Host                 :: xmpp_jid:raw_jid_component_bare(),
+  Node_Options         :: pubsub_options:options_node(),
+  Node_Owners          :: [Entity::xmpp_jid:usr_bare(),...],
+  Pubsub_State         :: mod_pubsub_dev:pubsub_state(),
+  Resource             :: undefined
+                        | xmpp_jid:resource_jid()
+                        | {'caps', xmpp_jid:resource_jid()},
+  Subscription_Options :: [] | pubsub_options:options_subscription(),
+  Pubsub_Features      :: exmpp_pubsub:pubsub_features())
+    -> {result,
+        Subscription_Subscribed :: exmpp_pubsub:subscription_subscribed(),
+        Pubsub_Last_Item        :: undefined | mod_pubsub_dev:pubsub_last_item()}
+     %
+     | {result,
+        Subscription_Pending :: exmpp_pubsub:subscription_pending(),
+        Pubsub_Last_Item     :: undefined}
+    %%%
+     | {error, 'forbidden'}
+     | {error, 'not-authorized', 'presence-subscription-required'}
+     | {error, 'not-authorized', 'not-in-roster-group'}
+     | {error, 'not-authorized', 'pending-subscription'}
+     | {error, 'not-allowed',    'closed-node'}
+).
+
+subscribe_node(Suffix, Host, Node_Options, Node_Owners,
+  #pubsub_state_dev{id = {{_U,S,_R} = Entity, _NodeIdx}} = Pubsub_State, Resource,
+  Subscription_Options, Pubsub_Features) ->
+    Affiliation = Pubsub_State#pubsub_state_dev.affiliation,
+    Subscriptions = Pubsub_State#pubsub_state_dev.subscriptions,
+    case
+        options_on_subscribe_node(Host, Node_Options, Node_Owners, Entity,
+            Resource, Affiliation, Subscriptions, Subscription_Options,
+            Pubsub_Features)
+    of
+        %%
+        {ok, 'new',
+         {'pending', SubId, _Resource, _Subscription_Options} = Subscription} ->
+            mnesia:write(table('pubsub_state', Suffix),
+                Pubsub_State#pubsub_state_dev{
+                    affiliation   = case Affiliation of
+                        'none'      -> 'member';
+                        Affiliation -> Affiliation
+                    end,
+                    subscriptions = [Subscription | Subscriptions]
+                },
+                write),
+            Table_Pubsub_Subscription_Pending = table('pubsub_subscription_pending',
+                Suffix),
+            case
+                mnesia:read(Table_Pubsub_Subscription_Pending,
+                    Pubsub_State#pubsub_state_dev.id, write)
+            of
+                [] ->
+                    mnesia:write(Table_Pubsub_Subscription_Pending,
+                        #pubsub_subscription_pending{
+                            id      = Pubsub_State#pubsub_state_dev.id,
+                            nodeidx = Pubsub_State#pubsub_state_dev.nodeidx,
+                            subids  = [SubId]
+                        },
+                        write);
+                [Pubsub_Subscription_Pending] ->
+                    mnesia:write(Table_Pubsub_Subscription_Pending,
+                        Pubsub_Subscription_Pending#pubsub_subscription_pending{
+                            subids = [SubId
+                                | Pubsub_Subscription_Pending
+                                      #pubsub_subscription_pending.subids]
+                        },
+                        write)
+            end,
+            {result, Subscription, _Pubsub_Last_Item = undefined};
+        %%
+        {ok, Type, Subscription} ->
+            case Type of
+                'new' ->
+                    mnesia:write(table('pubsub_state', Suffix),
+                        Pubsub_State#pubsub_state_dev{
+                            affiliation   = case Affiliation of
+                                'none'      -> 'member';
+                                Affiliation -> Affiliation
+                            end,
+                            subscriptions = [Subscription | Subscriptions]
+                        },
+                        write);
+                'old' ->
+                    ok
+            end,
+            {result,
+             Subscription,
+             _Pubsub_Last_Item = case
+                 (get_value(Subscription_Options, 'deliver', true) == true)
+                          andalso
+                 (get_value(Subscription_Options, 'show-values') =/= [])
+                          andalso
+                 (get_value(Node_Options, 'send_last_published_item', 'never')
+                      =/= 'never')
+             of
+                 true ->
+                     case
+                         mnesia:read(table('pubsub_last_item', Suffix),
+                             Pubsub_State#pubsub_state_dev.nodeidx,
+                             read)
+                     of
+                         []                 -> undefined;
+                         [Pubsub_Last_Item] -> Pubsub_Last_Item
+                     end;
+             false ->
+                 undefined
+             end};
+        Error ->
+            Error
+    end.
+
+%%
+-spec(options_on_subscribe_node/9 ::
+(
+  Host                 :: xmpp_jid:raw_jid_component_bare(),
+  Node_Options         :: pubsub_options:options_node(),
+  Node_Owners          :: [Entity::xmpp_jid:usr_bare(),...],
+  Entity               :: xmpp_jid:usr_bare(),
+  Resource             :: undefined
+                        | xmpp_jid:resource_jid()
+                        | {'caps', xmpp_jid:resource_jid()},
+  Affiliation          :: exmpp_pubsub:affiliation(),
+  Subscriptions        :: [] | exmpp_pubsub:subscriptions(),
+  Subscription_Options :: [] | pubsub_options:options_subscription(),
+  Pubsub_Features      :: exmpp_pubsub:pubsub_features())
+    -> {ok,
+        Type         :: 'new' | 'old',
+        Subscription :: exmpp_pubsub:subscription_subscribed()}
+     %
+     | {ok,
+        Type         :: 'new',
+        Subscription :: exmpp_pubsub:subscription_pending()}
+    %%%
+     | {error, 'forbidden'}
+     | {error, 'not-authorized', 'presence-subscription-required'}
+     | {error, 'not-authorized', 'not-in-roster-group'}
+     | {error, 'not-authorized', 'pending-subscription'}
+     | {error, 'not-allowed',    'closed-node'}
+).
+
+options_on_subscribe_node(Host, Node_Options, Node_Owners, Entity,
+  Resource, Affiliation, Subscriptions, Subscription_Options, Pubsub_Features) ->
+    options_on_subscribe_node(get_option(Node_Options, 'subscribe'), Host,
+        Node_Options, Node_Owners, Entity, Resource, Affiliation, Subscriptions,
+        Subscription_Options,
+        _Multi_Subscribe = lists:member(<<"multi-subscribe">>, Pubsub_Features)).
+
+%%
+-spec(options_on_subscribe_node/10 ::
+(
+  Option               :: pubsub_options:option_node_access_model()
+                        | pubsub_options:option_node_subscribe(),
+  Host                 :: xmpp_jid:raw_jid_component_bare(),
+  Node_Options         :: pubsub_options:options_node(),
+  Node_Owners          :: [Entity::xmpp_jid:usr_bare(),...],
+  Entity               :: xmpp_jid:usr_bare(),
+  Resource             :: undefined
+                        | xmpp_jid:resource_jid()
+                        | {'caps', xmpp_jid:resource_jid()},
+  Affiliation          :: exmpp_pubsub:affiliation(),
+  Subscriptions        :: [] | exmpp_pubsub:subscriptions(),
+  Subscription_Options :: [] | pubsub_options:options_subscription(),
+  Multi_Subscribe      :: boolean())
+    -> {ok,
+        Type         :: 'new' | 'old',
+        Subscription :: exmpp_pubsub:subscription_subscribed()}
+     %
+     | {ok,
+        Type         :: 'new',
+        Subscription :: exmpp_pubsub:subscription_pending()}
+    %%%
+     | {error, 'forbidden'}
+     | {error, 'not-authorized', 'presence-subscription-required'}
+     | {error, 'not-authorized', 'not-in-roster-group'}
+     | {error, 'not-authorized', 'pending-subscription'}
+     | {error, 'not-allowed',    'closed-node'}
+).
+
+options_on_subscribe_node({'subscribe', Subscribe}, _Host, _Node_Options,
+  _Node_Owners, _Entity, _Resource, Affiliation, _Subscriptions,
+  _Subscription_Options, _Multi_Subscribe)
+  when   Subscribe   == false
+  orelse Affiliation == 'outcast'
+  orelse Affiliation == 'publish-only' ->
+    {error, 'forbidden'};
+%%
+options_on_subscribe_node({'subscribe', true}, Host, Node_Options,
+  Node_Owners, Entity, Resource, Affiliation, Subscriptions,
+  Subscription_Options, Multi_Subscribe) ->
+    options_on_subscribe_node(get_option(Node_Options, 'access_model'), Host,
+        Node_Options, Node_Owners, Entity, Resource, Affiliation, Subscriptions,
+        Subscription_Options, Multi_Subscribe);
+
+options_on_subscribe_node({'access_model', open}, _Host, _Node_Options,
+  _Node_Owners, _Entity, Resource, _Affiliation, Subscriptions,
+  Subscription_Options, false = _Multi_Subscribe) ->
+    case lists:keyfind(Resource, 3, Subscriptions) of
+        {_Resource, Subscription} ->
+            {ok, 'old', Subscription};
+        false ->
+            {ok,
+             'new',
+             exmpp_pubsub:subscription_subscribed(Resource, Subscription_Options)}
+    end;
+%%
+options_on_subscribe_node({'access_model', open}, _Host, _Node_Options,
+  _Node_Owners, _Entity, Resource, _Affiliation, _Subscriptions,
+  Subscription_Options, true = _Multi_Subscribe) ->
+    {ok, 'new', exmpp_pubsub:subscription_subscribed(Resource, Subscription_Options)};
+%%
+options_on_subscribe_node({'access_model', presence}, _Host, _Node_Options,
+  _Node_Owners, _Entity, Resource, Affiliation, Subscriptions,
+  Subscription_Options, false = _Multi_Subscribe)
+  when   Affiliation == 'owner'
+  orelse Affiliation == 'publisher'
+  orelse Affiliation == 'member' ->
+    case lists:keyfind(Resource, 3, Subscriptions) of
+        {_Resource, Subscription} ->
+            {ok, 'old', Subscription};
+        false ->
+            {ok,
+             'new',
+             exmpp_pubsub:subscription_subscribed(Resource, Subscription_Options)}
+    end;
+%%
+options_on_subscribe_node({'access_model', presence}, _Host, _Node_Options,
+  _Node_Owners, _Entity, Resource, Affiliation, _Subscriptions,
+  Subscription_Options, true = _Multi_Subscribe)
+  when   Affiliation == 'owner'
+  orelse Affiliation == 'publisher'
+  orelse Affiliation == 'member' ->
+    {ok,
+     'new',
+     exmpp_pubsub:subscription_subscribed(Resource, Subscription_Options)};
+%%
+options_on_subscribe_node({'access_model', presence}, _Host, _Node_Options,
+  _Node_Owners, _Entity, Resource, Affiliation, Subscriptions,
+  Subscription_Options, false = _Multi_Subscribe)
+  when   Affiliation == 'owner'
+  orelse Affiliation == 'publisher'
+  orelse Affiliation == 'member' ->
+    case lists:keyfind(Resource, 3, Subscriptions) of
+        {_Resource, Subscription} ->
+            {ok, 'old', Subscription};
+        false ->
+            {ok,
+             'new',
+             exmpp_pubsub:subscription_subscribed(Resource, Subscription_Options)}
+    end;
+%%
+options_on_subscribe_node({'access_model', presence}, Host, _Node_Options,
+  Node_Owners, Entity, Resource, _Affiliation, _Subscriptions,
+  Subscription_Options, _Multi_Subscribe) ->
+    case is_contact_subscribed_to_node_owners(Host, Entity, Node_Owners) of
+        false ->
+            {error, 'not-authorized', 'presence-subscription-required'};
+        _Node_Owner ->
+            {ok,
+             'new',
+             exmpp_pubsub:subscription_subscribed(Resource, Subscription_Options)}
+    end;
+%%
+options_on_subscribe_node({'access_model', roster}, _Host, _Node_Options,
+  _Node_Owners, _Entity, Resource, Affiliation, _Subscriptions,
+  Subscription_Options, true = _Multi_Subscribe)
+  when   Affiliation == 'owner'
+  orelse Affiliation == 'publisher'
+  orelse Affiliation == 'member' ->
+    {ok,
+     'new',
+     exmpp_pubsub:subscription_subscribed(Resource, Subscription_Options)};
+%%
+options_on_subscribe_node({'access_model', roster}, _Host, _Node_Options,
+  _Node_Owners, _Entity, Resource, Affiliation, Subscriptions,
+  Subscription_Options, false = _Multi_Subscribe)
+  when   Affiliation == 'owner'
+  orelse Affiliation == 'publisher'
+  orelse Affiliation == 'member' ->
+    case lists:keyfind(Resource, 3, Subscriptions) of
+        {_Resource, Subscription} ->
+            {ok, 'old', Subscription};
+        false ->
+            {ok,
+             'new',
+             exmpp_pubsub:subscription_subscribed(Resource, Subscription_Options)}
+    end;
+%%
+options_on_subscribe_node({'access_model', roster}, _Host, Node_Options,
+  _Node_Owners, Entity, Resource, _Affiliation, _Subscriptions,
+  Subscription_Options, _Multi_Subscribe) ->
+    case
+        is_contact_in_allowed_roster_groups(Entity,
+            get_value(Node_Options, 'roster_groups_allowed', []))
+    of
+        false ->
+            {error, 'not-authorized', 'not-in-roster-group'};
+        {_Node_Owner, _Roster_Group} ->
+            {ok,
+             'new',
+             exmpp_pubsub:subscription_subscribed(Resource, Subscription_Options)}
+    end;
+%%
+options_on_subscribe_node({'access_model', authorize}, _Host, _Node_Options,
+  _Node_Owners, _Entity, Resource, Affiliation, _Subscriptions,
+  Subscription_Options, true = _Multi_Subscribe)
+  when   Affiliation == 'owner'
+  orelse Affiliation == 'publisher'
+  orelse Affiliation == 'member' ->
+    {ok,
+     'new',
+     exmpp_pubsub:subscription_subscribed(Resource, Subscription_Options)};
+%%
+options_on_subscribe_node({'access_model', authorize}, _Host, _Node_Options,
+  _Node_Owners, _Entity, Resource, Affiliation, Subscriptions,
+  Subscription_Options, false = _Multi_Subscribe)
+  when   Affiliation == 'owner'
+  orelse Affiliation == 'publisher'
+  orelse Affiliation == 'member' ->
+    case lists:keyfind(Resource, 3, Subscriptions) of
+        {_Resource, Subscription} ->
+            {ok, 'old', Subscription};
+        false ->
+            {ok,
+             'new',
+             exmpp_pubsub:subscription_subscribed(Resource, Subscription_Options)}
+    end;
+%%
+options_on_subscribe_node({'access_model', authorize}, _Host, _Node_Options,
+  _Node_Owners, _Entity, Resource, _Affiliation, Subscriptions,
+  Subscription_Options, false = _Multi_Subscribe) ->
+    case lists:keyfind(Resource, 3, Subscriptions) of
+        {_Resource, _Subscription} ->
+            {error, 'not-authorized', 'pending-subscription'};
+        false ->
+            {ok,
+             'new',
+             exmpp_pubsub:subscription_pending(Resource, Subscription_Options)}
+    end;
+%%
+options_on_subscribe_node({'access_model', whitelist}, _Host, _Node_Options,
+  _Node_Owners, _Entity, Resource, Affiliation, _Subscriptions,
+  Subscription_Options,  true = _Multi_Subscribe)
+  when   Affiliation == 'owner'
+  orelse Affiliation == 'publisher'
+  orelse Affiliation == 'member' ->
+    {ok,
+     'new',
+     exmpp_pubsub:subscription_subscribed(Resource, Subscription_Options)};
+%%
+options_on_subscribe_node({'access_model', whitelist}, _Host, _Node_Options,
+  _Node_Owners, _Entity, Resource, Affiliation, Subscriptions,
+  Subscription_Options, false = _Multi_Subscribe)
+  when   Affiliation == 'owner'
+  orelse Affiliation == 'publisher'
+  orelse Affiliation == 'member' ->
+    case lists:keyfind(Resource, 3, Subscriptions) of
+        {_Resource, Subscription} ->
+            {ok, 'old', Subscription};
+        false ->
+            {ok,
+             'new',
+             exmpp_pubsub:subscription_subscribed(Resource, Subscription_Options)}
+    end;
+%%
+options_on_subscribe_node({'access_model', whitelist}, _Host, _Node_Options,
+  _Node_Owners, _Entity, _Resource, _Affiliation, _Subscriptions,
+  _Subscription_Options, _Multi_Subscribe) ->
+    {error, 'not-allowed', 'closed-node'}.
+
+
+%-- Unsubscribe_Node --%
+-spec(unsubscribe_node/6 ::
+(
+  Suffix            :: atom(),
+  Host              :: xmpp_jid:raw_jid_component_bare(),
+  Node_Access_Model :: pubsub_options:access_model(),
+  Pubsub_State      :: mod_pubsub_dev:pubsub_state_member()
+                     | mod_pubsub_dev:pubsub_state_outcast()
+                     | mod_pubsub_dev:pubsub_state_owner()
+                     | mod_pubsub_dev:pubsub_state_publisher(),
+  Resource          :: undefined
+                     | xmpp_jid:resource_jid()
+                     | {'caps', xmpp_jid:resource_jid()},
+  SubId             :: undefined | exmpp_pubsub:subId())
+    -> {ok,
+        Resource :: undefined
+                  | xmpp_jid:resource_jid()
+                  | {'caps', xmpp_jid:resource_jid()},
+        SubId    :: exmpp_pubsub:subId()}
+    %%%
+     | {error, 'unexpected',     'not-subscribed'}
+     | {error, 'not-acceptable', 'invalid-subid'}
+     | {error, 'bad-request',    'subid-required'}
+     | {error, 'not-acceptable', 'invalid-subid'}
+).
+
+unsubscribe_node(Suffix, Host, Node_Access_Model,
+  #pubsub_state_dev{subscriptions = [{Subscription_State, SubId, Resource, _}]}
+  = Pubsub_State, Resource, _SubId)
+  when _SubId == undefined orelse _SubId == SubId ->
+    mnesia:write(table('pubsub_state', Suffix),
+        Pubsub_State#pubsub_state_dev{
+            subscriptions = []
+        },
+        write),
+    %% unregister pending subscription
+    case Subscription_State of
+        'pending' ->
+            unregister_pending_subscription(Suffix,
+                Pubsub_State#pubsub_state_dev.id, SubId);
+        _ ->
+            ok
+    end,
+    case Node_Access_Model of
+        'roster' ->
+            ok;
+        _ ->
+            ok
+    end,
+    {ok, Resource, SubId};
+%%
+unsubscribe_node(Suffix, Host, Node_Access_Model,
+  #pubsub_state_dev{subscriptions = [{_Subscription_State, SubId, _Resource, _}]}
+  = Pubsub_State, Resource, SubId) ->
+    {error, 'unexpected', 'not-subscribed'};
+%%
+unsubscribe_node(Suffix, Host, Node_Access_Model,
+  #pubsub_state_dev{subscriptions = [{_Subscription_State, _SubId, Resource, _}]}
+  = Pubsub_State, Resource, SubId) ->
+    {error, 'not-acceptable', 'invalid-subid'};
+%%
+unsubscribe_node(Suffix, Host, Node_Access_Model, Pubsub_State, Resource,
+  undefined = _SubId) ->
+    case lists:keytake(Resource, 3, Pubsub_State#pubsub_state_dev.subscriptions) of
+        {value,
+         {Subscription_State, SubId, Resource, _} = Subscription, Subscriptions} ->
+            case lists:keymember(Resource, 3, Subscriptions) of
+                false ->
+                    mnesia:write(table('pubsub_state', Suffix),
+                        Pubsub_State#pubsub_state_dev{
+                            subscriptions = Subscriptions
+                        },
+                        write),
+                    %% unregister pending subscription
+                    case Subscription_State of
+                        'pending' ->
+                            unregister_pending_subscription(Suffix,
+                                Pubsub_State#pubsub_state_dev.id, SubId);
+                        _ ->
+                            ok
+                    end,
+                    case Node_Access_Model of
+                        'roster' ->
+                            ok;
+                        _ ->
+                            ok
+                    end,
+                    %% TODO : unregister 'pubsub#tempsub'
+                    {ok, Resource, SubId};
+                true ->
+                    {error, 'bad-request', 'subid-required'}
+            end;
+        false ->
+            {error, 'unexpected', 'not-subscribed'}
+    end;
+%%
+unsubscribe_node(Suffix, Host, Node_Access_Model, Pubsub_State, Resource, SubId) ->
+    case lists:keytake(SubId, 2, Pubsub_State#pubsub_state_dev.subscriptions) of
+        {value,
+         {Subscription_State, SubId, Resource, _} = Subscription, Subscriptions} ->
+            mnesia:write(table('pubsub_state', Suffix),
+                Pubsub_State#pubsub_state_dev{
+                    subscriptions = Subscriptions
+                },
+                write),
+                %% unregister pending subscription
+                case Subscription_State of
+                    'pending' ->
+                        unregister_pending_subscription(Suffix,
+                            Pubsub_State#pubsub_state_dev.id, SubId);
+                    _ ->
+                        ok
+                end,
+                case Node_Access_Model of
+                    'roster' ->
+                        ok;
+                    _ ->
+                        ok
+                end,
+                {ok, Resource, SubId};
+        {value, {_Subscription_State, SubId, _Resource, _} = Subscription, _} ->
+            {error, 'unexpected', 'not-subscribed'};
+        false ->
+            {error, 'not-acceptable', 'invalid-subid'}
+    end.
+
+%%
+-spec(register_pending_subscription/3 ::
+(
+  Suffix  :: atom(),
+  StateId :: {Entity::xmpp_jid:usr_bare(), NodeIdx::exmpp_pubsub:nodeIdx()},
+  SubId   :: exmpp_pubsub:subId())
+    -> 'ok'
+).
+
+register_pending_subscription(Suffix, {Entity, NodeIdx} = _StateId, SubId) ->
+    Table_Pubsub_Subscription_Pending = table('pubsub_subscription_pending', Suffix),
+    case mnesia:read(Table_Pubsub_Subscription_Pending, {Entity, NodeIdx}, write) of
+        [] ->
+            mnesia:write(Table_Pubsub_Subscription_Pending,
+                #pubsub_subscription_pending{
+                    id      = {Entity, NodeIdx},
+                    nodeidx = NodeIdx,
+                    subids  = [SubId]
+                },
+                write);
+        [Pubsub_Subscription_Pending] ->
+            mnesia:write(Table_Pubsub_Subscription_Pending,
+                Pubsub_Subscription_Pending#pubsub_subscription_pending{
+                    subids = [SubId
+                        | Pubsub_Subscription_Pending
+                              #pubsub_subscription_pending.subids]
+                },
+                write)
+    end.
+
+%%
+-spec(unregister_pending_subscription/3 ::
+(
+  Suffix  :: atom(),
+  StateId :: {Entity::xmpp_jid:usr_bare(), NodeIdx::exmpp_pubsub:nodeIdx()},
+  SubId   :: exmpp_pubsub:subId())
+    -> 'ok'
+).
+
+unregister_pending_subscription(Suffix, StateId, SubId) ->
+    Table_Pubsub_Subscription_Pending = table('pubsub_subscription_pending', Suffix),
+    case mnesia:read(Table_Pubsub_Subscription_Pending, StateId, write) of
+        %%
+        [#pubsub_subscription_pending{subids = [SubId]} = Pubsub_Subscription_Pending] ->
+            mnesia:delete_object(Table_Pubsub_Subscription_Pending,
+                Pubsub_Subscription_Pending, write);
+        %%
+        [Pubsub_Subscription_Pending] ->
+            mnesia:write(Table_Pubsub_Subscription_Pending,
+                Pubsub_Subscription_Pending#pubsub_subscription_pending{
+                    subids = lists:delete(SubId,
+                        Pubsub_Subscription_Pending#pubsub_subscription_pending.subids)
+                    },
+                write);
+        [] ->
+            ok
+    end.
+
+%-- Set_Configure_Subscription --%
+-spec(set_configure_subscription/5 ::
+(
+  Suffix               :: atom(),
+  Pubsub_State         :: mod_pubsub_dev:pubsub_state_member()
+                        | mod_pubsub_dev:pubsub_state_owner()
+                        | mod_pubsub_dev:pubsub_state_publisher(),
+  SubId                :: undefined | exmpp_pubsub:subId(),
+  Resource             :: undefined
+                        | xmpp_jid:resource_jid()
+                        | {'caps', xmpp_jid:resource_jid()},
+  Subscription_Options :: pubsub_options:options_subscription())
+    -> 'ok'
+    %%%
+     | {error, 'unexpected-request', 'not-subscribed'}
+     | {error, 'bad-request',        'subid-required'}
+     | {error, 'forbidden'}
+     | {error, 'not-acceptable',     'invalid-subid'}
+).
+
+set_configure_subscription(Suffix, Pubsub_State, undefined = _SubId, Resource,
+  Subscription_Options) ->
+    case
+        lists:keytake(Resource, 3, Pubsub_State#pubsub_state_dev.subscriptions)
+    of
+        {value, {Subscription_State, SubId, Resource, _Subscription_Options},
+         Subscriptions} ->
+            case lists:keymember(Resource, 3, Subscriptions) of
+                false
+                  when Subscription_State == 'pending' ->
+                    {error, 'forbidden'};
+                false ->
+                    mnesia:write(table('pubsub_state', Suffix),
+                        Pubsub_State#pubsub_state_dev{
+                            subscriptions = [
+                                {Subscription_State, SubId, Resource,
+                                 Subscription_Options}
+                                | Subscriptions]
+                        },
+                        write),
+                    'ok';
+                true ->
+                    {error, 'bad-request', 'subid-required'}
+            end;
+         false ->
+            {error, 'unexpected-request', 'not-subscribed'}
+    end;
+%%
+set_configure_subscription(Suffix, Pubsub_State, SubId, Resource,
+  Subscription_Options) ->
+    case lists:keytake(SubId, 2, Pubsub_State#pubsub_state_dev.subscriptions) of
+        {value, {'pending', SubId, Resource, _Subscription_Options},
+         _Subscriptions} ->
+            {error, 'forbidden'};
+        {value, {Subscription_State, SubId, Resource, _Subscription_Options},
+         Subscriptions} ->
+            mnesia:write(table('pubsub_state', Suffix),
+                Pubsub_State#pubsub_state_dev{
+                    subscriptions = [
+                        {Subscription_State, SubId, Resource,
+                            Subscription_Options}
+                        | Subscriptions]
+                },
+                write),
+                'ok';
+        {value, {_Subscription_State, SubId, _Resource, _Subscription_Options},
+         _Subscriptions} ->
+            {error, 'unexpected-request', 'not-subscribed'};
+        false ->
+            case
+                lists:keytake(Resource, 3,
+                    Pubsub_State#pubsub_state_dev.subscriptions)
+            of
+                {value, {'pending', _SubId, Resource, _Subscription_Options},
+                 _Subscriptions} ->
+                    {error, 'forbidden'};
+                {value, {_Subscription_State, _SubId, _Resource, _Subscription_Options},
+                 _Subscriptions} ->
+                    {error, 'not-acceptable', 'invalid-subid'};
+                false ->
+                    {error, 'unexpected-request', 'not-subscribed'}
+            end
+    end.
+
+%-- Get_Items --%
+-spec(get_items/5 ::
+(
+  Suffix            :: pubsub_db_mnesia:table(),
+  Host              :: xmpp_jid:raw_jid_component_bare(),
+  Node_Parameters   :: {NodeIdx           :: exmpp_pubsub:nodeIdx(),
+                        Node_Owners       :: mod_pubsub_dev:node_owners(),
+                        Node_ItemIds      :: [] | exmpp_pubsub:itemIds(),
+                        Node_Access_Model :: pubsub_options:access_model(),
+                        Node_Groups       :: pubsub_options:rosters_groups_allowed()},
+  %%
+  Entity_Parameters :: {Entity      :: xmpp_jid:usr_bare(),
+                        Affiliation :: exmpp_pubsub:affiliation(),
+                        Access      :: undefined | 'pending' | 'roster' | 'presence' | 'authorize'},
+  %%
+  Criteria          :: {Max_Items :: non_neg_integer(),
+                        ItemIds   :: undefined,
+                        _SubId    :: exmpp_pubsub:subId()}
+                     | {Max_Items :: undefined,
+                        ItemIds   :: exmpp_pubsub:itemIds(),
+                        _SubId    :: exmpp_pubsub:subId()})
+    -> {ok,
+        Pubsub_Items :: [] | mod_pubsub_dev:pubsub_items(),
+        Cache        :: {Presence_Cache :: undefined,
+                         Groups_Cache   :: undefined}}
+     %
+     | {ok,
+        Pubsub_Items :: [] | mod_pubsub_dev:pubsub_items(),
+        Cache        :: {Presence_Cache :: true,
+                         Groups_Cache   :: undefined}}
+     %
+     | {ok,
+        Pubsub_Items :: [] | mod_pubsub_dev:pubsub_items(),
+        Cache        :: {Presence_Cache :: undefined,
+                         Groups_Cache   :: [{Node_Owner :: xmpp_jid:usr_bare(),
+                                             Groups     :: [Group::binary()]}]}}
+    %%%
+     | {error, 'forbidden'}
+     | {error, 'not-authorized', 'presence-subscription-required'}
+     | {error, 'not-authorized', 'not-in-roster-group'}
+     | {error, 'not-allowed',    'closed-node'}
+).
+
+get_items(_Suffix, _Host, _Node_Parameters, {_Entity, Affiliation, Access}, _Criteria)
+  when   Affiliation == 'outcast'
+  orelse Affiliation == 'publish-only'
+  orelse Access      == 'pending' ->
+    {error, 'forbidden'};
+%%
+get_items(Suffix, _Host,
+  {NodeIdx, _Node_Owners, Node_ItemIds, Node_Access_Model, _Node_Groups},
+  {_Entity, Affiliation, Access}, {Max_Items, ItemIds, _SubId})
+  when   Affiliation        == 'owner'
+  %
+  orelse Affiliation        == 'publisher'
+  %
+  orelse Affiliation        == 'member'
+  %
+  orelse Node_Access_Model  == 'open'
+  %
+  orelse (Node_Access_Model == 'presence'
+      andalso
+          Access == 'presence'
+              orelse Access == 'roster')
+  %
+  orelse (Node_Access_Model == 'roster'
+      andalso
+          Access == 'roster')
+  %
+  orelse (Node_Access_Model == 'authorize'
+      andalso
+          Access == 'authorize') ->
+    {ok,
+     _Pusbub_Items = get_items(Suffix, NodeIdx,
+         get_max_itemids(Max_Items, ItemIds, Node_ItemIds)),
+     _Cache = {undefined, undefined}};
+%
+get_items(Suffix, Host,
+  {NodeIdx, Node_Owners, Node_ItemIds, 'presence' = _Node_Access_Model, _Node_Groups},
+  {Entity, _Affiliation, _Access}, {Max_Items, ItemIds, _SubId}) ->
+    case is_contact_subscribed_to_node_owners(Host, Entity, Node_Owners) of
+        false ->
+            {error, 'not-authorized', 'presence-subscription-required'};
+        Node_Owner ->
+            {ok,
+             _Pusbub_Items = get_items(Suffix, NodeIdx,
+                 get_max_itemids(Max_Items, ItemIds, Node_ItemIds)),
+             _Cache = {_Presence_Cache = true, _Groups_Cache = undefined}}
+    end;
+%%
+get_items(Suffix, _Host,
+  {NodeIdx, _Node_Owners, Node_ItemIds, 'roster' = _Node_Access_Model, Node_Groups},
+  {Entity, _Affiliation, _Access}, {Max_Items, ItemIds, _SubId}) ->
+    case is_contact_in_allowed_roster_groups(Entity, Node_Groups) of
+        {Node_Owner, Roster_Group} ->
+            {ok,
+             _Pusbub_Items = get_items(Suffix, NodeIdx,
+                 get_max_itemids(Max_Items, ItemIds, Node_ItemIds)),
+             _Cache = {
+                 _Presence_Cache = undefined,
+                 _Groups_Cache = [{Node_Owner, [Roster_Group]}]
+             }
+            };
+        false ->
+            {error, 'not-authorized', 'not-in-roster-group'}
+    end;
+%%
+get_items(_Suffix, _Host,
+  {_NodeIdx, _Node_Owners, _Node_ItemIds, 'authorize' = _Node_Access_Model, _Node_Groups},
+  _Entity_Parameters, _Criteria) ->
+    {error, 'not-allowed', 'closed-node'};
+%%
+get_items(_Suffix, _Host, _Node_Parameters, _Entity_Parameters, _Criteria) ->
+    {error, 'forbidden'}.
+
+%%
+-spec(get_max_itemids/3 ::
+(
+  Max_Items    :: undefined | non_neg_integer(),
+  ItemIds      :: [] | exmpp_pubsub:itemIds(),
+  Node_ItemIds :: [] | exmpp_pubsub:itemIds())
+    -> Max_ItemIds :: undefined | [] | exmpp_pubsub:itemIds()
+).
+
+get_max_itemids(undefined = _Max_Items, [] = _ItemIds, _Node_ItemIds) ->
+    _Max_ItemIds = undefined;
+%%
+get_max_itemids(undefined = _Max_Items, ItemIds, Node_ItemIds) ->
+    _Max_ItemIds = lists:filter(fun
+        (ItemId) ->
+            lists:member(ItemId, Node_ItemIds)
+    end, ItemIds);
+%%
+get_max_itemids(Max_Items, undefined = _ItemIds, Node_ItemIds) ->
+    _Max_ItemIds = get_max_itemids(Max_Items, [], Node_ItemIds);
+%%
+get_max_itemids(_Max_Items, ItemIds, _Node_ItemIds)
+  when _Max_Items == 0 orelse _Node_ItemIds == [] ->
+    _Max_ItemIds = lists:reverse(ItemIds);
+%%
+get_max_itemids(Max_Items, ItemIds, [ItemId | Node_ItemIds]) ->
+    get_max_itemids(Max_Items - 1, [ItemId | ItemIds], Node_ItemIds).
+
+%%
+-spec(get_items/3 ::
+(
+  Suffix  :: pubsub_db_mnesia:suffix(),
+  NodeIdx :: exmpp_pubsub:nodeIdx(),
+  ItemIds :: undefined | [] | exmpp_pubsub:itemIds())
+    -> Pubsub_Items :: [] | mod_pubsub_dev:pubsub_items()
+).
+
+get_items(Suffix, NodeIdx, undefined = _ItemIds) ->
+    _Pubsub_Items = mnesia:index_read(table('pubsub_item', Suffix), NodeIdx, nodeidx);
+%%
+get_items(Suffix, NodeIdx, ItemIds) ->
+    Table_Pubsub_Item = table('pubsub_item', Suffix),
+    _Pubsub_Items = lists:foldl(fun
+        (ItemId, Pubsub_Items) ->
+            case
+                mnesia:index_match_object(Table_Pubsub_Item,
+                    #pubsub_item_dev{
+                        id      = {ItemId, NodeIdx},
+                        nodeidx = NodeIdx,
+                        _       = '_'
+                    },
+                    nodeidx,
+                    read)
+            of
+                [Pubsub_Item] -> [Pubsub_Item | Pubsub_Items];
+                _             -> Pubsub_Items
+            end
+    end, [], ItemIds).
diff --git a/src/mod_pubsub_ng/pubsub_dev.hrl b/src/mod_pubsub_ng/pubsub_dev.hrl
new file mode 100644
index 000000000..9a695ca16
--- /dev/null
+++ b/src/mod_pubsub_ng/pubsub_dev.hrl
@@ -0,0 +1,146 @@
+
+
+%-include_lib("exmpp/include/exmpp.hrl").
+%-include_lib("exmpp/include/exmpp_jid.hrl").
+-include("ejabberd.hrl").
+-include("mod_roster.hrl").
+-include("jlib.hrl").
+%-include("pubsub_api.hrl").
+
+-define(NS_JABBER_CLIENT, <<"jabber:client">>).
+
+%%
+%% Pubsub Node
+-record(pubsub_node_dev,
+{
+  id            ,%:: {Pubsub_Host :: exmpp_pubsub:host(),
+                 %   NodeId      :: undefined | exmpp_pubsub:nodeId()},
+  idx           ,%:: exmpp_pubsub:nodeIdx(),
+  creation      ,%:: {DateTime::erlang:timestamp(), Entity::xmpp_jid:usr_entity()},
+  level    = 0  ,%:: exmpp_pubsub:level(),
+  owners   = [] ,%:: [Owner::xmpp_jid:usr_bare(),...],
+  itemids  = [] ,%:: [ItemId::exmpp_pubsub:itemId()],
+  options  = []  %:: pubsub_options:options_node()
+}).
+
+%%
+%% Pubsub State
+-record(pubsub_state_dev,
+{
+  id                     ,%:: {Entity  :: xmpp_jid:usr_bare(),
+                          %   NodeIdx :: exmpp_pubsub:nodeIdx()},
+  nodeidx                ,%:: exmpp_pubsub:nodeIdx(),
+  affiliation   = 'none' ,%:: exmpp_pubsub:affiliation(),
+  access                 ,%:: pubsub_options:access_model(),
+  subscriptions = []     ,%:: [] | exmpp_pubsub:subscriptions(),
+ %groups        = []     ,%:: [Roster_Group::binary()],
+  itemids       = []      %:: [ItemId::exmpp_pubsub:itemId()]
+}).
+
+%%
+%% Pubsub Item
+-record(pubsub_item_dev,
+{
+  id           ,%:: {ItemId::exmpp_pubsub:itemId(), NodeIdx::exmpp_pubsub:nodeIdx()},
+  nodeidx      ,%:: exmpp_pubsub:nodeIdx(),
+  owners = []  ,%:: [Owner::xmpp_jid:usr_bare(),...],
+  creation     ,%:: {DateTime::erlang:timestamp(), Entity::xmpp_jid:usr_entity()},
+  modification ,%:: {DateTime::erlang:timestamp(), Entity::xmpp_jid:usr_entity()},
+  payload      ,%:: exmpp_pubsub:payload(),
+  options = []  %:: [] | pubsub_options:options_item()
+}).
+
+%%
+%% Pubsub Last Item
+-record(pubsub_last_item_dev,
+{
+  nodeidx      ,%:: exmpp_pubsub:nodeIdx(),
+  id           ,%:: exmpp_pubsub:itemId(),
+  owners  = [] ,%:: [Owner::xmpp_jid:usr_bare(),...],
+  creation     ,%:: {DateTime::erlang:timestamp(), Entity::xmpp_jid:usr_entity()},
+  payload      ,%:: exmpp_pubsub:payload(),
+  options = []  %:: [] | pubsub_options:options_item()
+}).
+
+%%
+%% Pubsub Index
+-record(pubsub_index_dev,
+{
+  index :: exmpp_pubsub:index(),
+  last  :: exmpp_pubsub:nodeIdx(),
+  free  :: [exmpp_pubsub:nodeIdx()]
+}).
+
+%%
+%% Pubsub_Subscription_Pending
+-record(pubsub_subscription_pending,
+{
+  id      ,%:: {Entity::xmpp_jid:usr_bare(), NodeIdx::exmpp_pubsub:nodeIdx()}
+  nodeidx ,%:: exmpp_pubsub:nodeIdx()
+  subids   %:: [SubId::exmpp_pubsub:subId(),...]
+}).
+
+
+
+%%
+%% Internal data structures
+%%
+-record(entity,
+{
+  id            :: xmpp_jid:usr_bare(),
+  local         :: boolean(),
+  affiliation   :: 'member' | 'owner' | 'publisher',
+  subscriptions :: []%[exmpp_pubsub:subscription(),...]
+}).
+
+%%
+-record(node,
+{
+  id                           :: exmpp_pubsub:nodeId(),
+  owners                       :: [Node_Owner::xmpp_jid:usr_bare(),...],
+  access_model                 :: pubsub_options:access_model(),
+% itemreply                    :: 'owner' | 'publisher',
+% notification_type            :: 'headline' | 'normal',
+% presence_based_delivery      :: boolean(),
+  rosters_groups_allowed  = [] :: [] | pubsub_options:rosters_groups_allowed()
+}).
+
+%%
+-record(item,
+{
+  access_model                ,%:: undefined | pubsub_options:access_model(),
+  presence_based_delivery     ,%:: undefined | boolean(),
+  rosters_groups_allowed  = [],%:: [] | pubsub_options:rosters_groups_allowed()
+  stanza                       %::#xmlel{}
+}).
+
+%%
+-record(cache,
+{
+  %% Entity is online
+  presence               :: undefined | mod_pubsub_dev:presence_cache(),
+  %% Entity has presence subscriptions with at least one node owner
+  presence_subscriptions :: undefined | boolean(),
+  %% Entity has presence subscriptions with at least one node owner
+  %% and is contained in at least one roster group from the node owner
+  rosters_groups         :: undefined | boolean() %% TODO : use a list
+}).
+
+%%
+-record(subids,
+{
+  presence    = undefined :: undefined | [] | mod_pubsub_dev:resources_subids(),
+  no_presence = undefined :: undefined | [] | mod_pubsub_dev:resources_subids()
+}).
+
+%%
+-record(event,
+{
+  host      :: xmpp_jid:raw_jid_component_bare(),
+  component :: xmpp_jid:component_bare(),
+  entity    :: mod_pubsub_dev:entity(),
+  node      :: mod_pubsub_dev:n0de(),
+  cache     :: mod_pubsub_dev:cache(),
+  subids    :: mod_pubsub_dev:subids()
+}).
+
diff --git a/src/mod_pubsub_ng/pubsub_disco.erl b/src/mod_pubsub_ng/pubsub_disco.erl
new file mode 100644
index 000000000..935e4f47e
--- /dev/null
+++ b/src/mod_pubsub_ng/pubsub_disco.erl
@@ -0,0 +1,1437 @@
+%%% ====================================================================
+%%% ``The contents of this file are subject to the Erlang Public License,
+%%% Version 1.1, (the "License"); you may not use this file except in
+%%% compliance with the License. You should have received a copy of the
+%%% Erlang Public License along with this software. If not, it can be
+%%% retrieved via the world wide web at http://www.erlang.org/.
+%%% 
+%%% Software distributed under the License is distributed on an "AS IS"
+%%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%%% the License for the specific language governing rights and limitations
+%%% under the License.
+%%% 
+%%% The Initial Developer of the Original Code is ProcessOne.
+%%% Portions created by ProcessOne are Copyright 2006-2011, ProcessOne
+%%% All Rights Reserved.''
+%%% This software is copyright 2006-2011, ProcessOne.
+%%%
+%%% @copyright 2006-2011 ProcessOne
+%%% @author Karim Gemayel <karim.gemayel@process-one.net>
+%%%   [http://www.process-one.net/]
+%%% @version {@vsn}, {@date} {@time}
+%%% @end
+%%% ====================================================================
+
+%%% @headerfile "pubsub_dev.hrl"
+
+-module(pubsub_disco).
+-author('karim.gemayel@process-one.net').
+
+-compile(export_all).
+
+-include("pubsub_dev.hrl").
+
+-import(pubsub_tools,
+[
+  get_option/2,
+  get_option/3,
+  get_value/2,
+  get_value/3,
+  set_value/3,
+  %%
+  check_access_model/3,
+  check_access_model/7,
+  check_publish_model/3,
+  is_contact_subscribed_to_node_owners/3,
+  is_contact_in_allowed_roster_groups/2,
+  has_subscriptions/1
+]).
+
+
+-import(pubsub_db_mnesia,
+[
+  table/2
+]).
+
+-import(xmpp_xdata,
+[
+  xmlel_field/3,
+  xmlel_field_jid_multi/3,
+  xmlel_field_jid_single/3,
+  xmlel_field_list_single/4,
+  xmlel_field_text_single/3,
+  xmlel_x/2
+]).
+
+%%
+-spec(iq_disco_info/9 ::
+(
+  Suffix      :: undefined | atom(),
+  Host        :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host :: exmpp_pubsub:host_pubsub(),
+  Privacy     :: boolean(),
+  Entity      :: xmpp_jid:usr_bare(),
+  Entity_Type :: 'local' | 'remote',
+  Plugin      :: exmpp_pubsub:plugin(),
+  NodeId      :: undefined | exmpp_pubsub:nodeId(),
+  Xmlels      :: [] | [Xmlel_Set::xmlel(),...])
+    -> {result, Xmlel_Query::xmlel()}
+    %%%
+%     | {error, 'feature-not-implemented', ?NS_DISCO_INFO}
+%     | {error, 'feature-not-implemented', ?NS_PUBSUB_META_DATA}
+%     %
+%     | {error, 'item-not-found'}
+).
+
+iq_disco_info(_Suffix, Host, Pubsub_Host, _Privacy, _Entity, Entity_Type,
+  Plugin, undefined = _NodeId, _Xmlels) ->
+    Features = Plugin:features(),
+    case lists:member(?NS_DISCO_INFO, Plugin:features()) of
+        true ->
+            {result,
+             exmpp_pubsub:xmlel_query('disco#info',
+                 lists:map(fun
+                     ({Category, Name, Type}) ->
+                         exmpp_pubsub:xmlel_identity('disco#info',
+                             Category, Type, Name)
+                 end, Plugin:identity())
+                 ++
+                 lists:map(fun
+                    (Feature) ->
+                        exmpp_pubsub:xmlel_feature('disco#info', Feature)
+                 end, Features)
+                 ++
+                 lists:map(fun
+                    (Pubsub_Feature) ->
+                        exmpp_pubsub:xmlel_feature('disco#info',
+                            <<?NS_PUBSUB/binary, "#", Pubsub_Feature/binary>>)
+                 end, lists:sort(Plugin:pubsub_features(Entity_Type)))
+                 )
+             };
+        false ->
+            {error, 'feature-not-implemented', ?NS_DISCO_INFO}
+    end;
+%%
+iq_disco_info(Suffix, Host, Pubsub_Host, false = _Privacy, {_,S,_} = _Entity,
+  Entity_Type, Plugin, NodeId, _Xmlels) ->
+    Features = Plugin:features(),
+    case lists:member(?NS_DISCO_INFO, Features) of
+        true ->
+            case
+                mnesia:dirty_read(table('pubsub_node', Suffix),
+                    {Pubsub_Host, NodeId})
+            of
+                [#pubsub_node_dev{idx = NodeIdx, owners = Node_Owners,
+                 options = Node_Options, creation = Creation}] ->
+                Pubsub_Features = Plugin:pubsub_features(Entity_Type),
+                {result,
+                 exmpp_pubsub:xmlel_query('disco#info', NodeId,
+                     [exmpp_pubsub:xmlel_identity('disco#info', <<"pubsub">>,
+                          get_value(Node_Options, 'node_type'),
+                          get_value(Node_Options, 'title', undefined))]
+                     ++
+                     [exmpp_pubsub:xmlel_identity('disco#info', Category, Type, Name)
+                     || {Category, Name, Type} <- Plugin:identity()]
+                     ++
+                     [exmpp_pubsub:xmlel_feature('disco#info', Feature)
+                     || Feature <- Features]
+                     ++
+                     [exmpp_pubsub:xmlel_feature('disco#info',
+                          <<?NS_PUBSUB/binary, "#", Pubsub_Feature/binary>>)
+                     || Pubsub_Feature <- Pubsub_Features]
+                     ++
+                     case lists:member(<<"meta-data">>, Pubsub_Features) of
+                        true ->
+                            [xmlel_x_metadata(table('pubsub_state', Suffix),
+                                 NodeIdx, Node_Owners, Creation,
+                                 Node_Options)];
+                        false ->
+                            []
+                     end)};
+                _ ->
+                    {error, 'item-not-found'}
+            end;
+        false ->
+            {error, 'feature-not-implemented', ?NS_DISCO_INFO}
+    end.
+
+%%
+-spec(xmlel_x_metadata/5 ::
+(
+  Table_Pubsub_State :: atom(),
+  NodeIdx      :: exmpp_pubsub:nodeIdx(),
+  Node_Owners  :: mod_pubsub_dev:node_owners(),
+  Creation     :: mod_pubsub_dev:node_creation(),
+  Node_Options :: pubsub_options:options_node())
+    -> Xmlel::xmlel()
+).
+
+%% <x xmlns='jabber:x:data' type='result'>
+%%  <field var='FORM_TYPE' type='hidden'>
+%%   <value>http://jabber.org/protocol/pubsub#meta-data</value>
+%%  </field>
+%%  <field var='pubsub#type' label='Payload type' type='text-single'>
+%%   <value>http://www.w3.org/2005/Atom</value>
+%%  </field>
+%%  <field var='pubsub#creator' label='Node creator' type='jid-single'>
+%%   <value>hamlet@denmark.lit</value>
+%%  </field>
+%%  <field var='pubsub#creation_date' label='Creation date' type='text-single'>
+%%   <value>2003-07-29T22:56Z</value>
+%%  </field>
+%%  <field var='pubsub#title' label='A short name for the node' type='text-single'>
+%%   <value>Princely Musings (Atom)</value>
+%%  </field>
+%%  <field var='pubsub#description' label='A description of the node' type='text-single'>
+%%   <value>Updates for Hamlet&apos;s Princely Musings weblog.</value>
+%%  </field>
+%%  <field var='pubsub#language' label='Default language' type='list-single'>
+%%   <value>en</value>
+%%  </field>
+%%  <field var='pubsub#contact' label='People to contact with questions' type='jid-multi'>
+%%   <value>bard@shakespeare.lit</value>
+%%  </field>
+%%  <field var='pubsub#owner' label='Node owners' type='jid-multi'>
+%%   <value>hamlet@denmark.lit</value>
+%%  </field>
+%%  <field var='pubsub#publisher' label='Publishers to this node' type='jid-multi'>
+%%   <value>hamlet@denmark.lit</value>
+%%  </field>
+%%  <field var='pubsub#num_subscribers' label='Number of subscribers to this node' type='text-single'>
+%%   <value>1066</value>
+%%  </field>
+%% </x>
+
+xmlel_x_metadata(_Table_Pubsub_State, _NodeIdx, Node_Owners,
+  {TimeStamp, Creator} = _Creation, Node_Options) ->
+    {DateTime, _} = jlib:timestamp_to_iso(calendar:now_to_datetime(TimeStamp), utc),
+    Creation_Date = list_to_binary(DateTime ++ "Z"),
+    xmlel_x(<<"form">>, [
+        xmlel_field(<<"FORM_TYPE">>, <<"result">>, [?NS_PUBSUB_META_DATA]),
+        %
+        xmlel_field_text_single(<<"pubsub#type">>, <<"Payload type">>,
+            get_value(Node_Options, 'type', undefined)),
+        %
+        xmlel_field_jid_single(<<"pubsub#creator">>, <<"Node creator">>,
+            pubsub_tools:jid_to_string(Creator)),
+        %
+        xmlel_field_text_single(<<"pubsub#creation_date">>, <<"Creation date">>,
+            Creation_Date),
+        %
+        xmlel_field_text_single(<<"pubsub#title">>, <<"Node title">>,
+            get_value(Node_Options, 'title', undefined)),
+        %
+        xmlel_field_text_single(<<"pubsub#description">>, <<"Node description">>,
+            get_value(Node_Options, 'description', undefined)),
+        %
+        xmlel_field_list_single(<<"pubsub#language">>, <<"Default language">>,
+            get_value(Node_Options, 'language', <<"en">>), []),
+        %
+        xmlel_field_jid_multi(<<"pubsub#contact">>,
+            <<"People to contact with questions">>,
+            get_value(Node_Options, 'contact', [])),
+        %
+        xmlel_field_jid_multi(<<"pubsub#owner">>, <<"Node owners">>,
+            [pubsub_tools:jid_to_string(Node_Owner) || Node_Owner <- Node_Owners])
+        %
+%        xmlel_field_jid_multi(<<"pubsub#publisher">>,
+%            <<"Publishers to this node">>,
+%            [pubsub_tools:jid_to_string(Publisher)
+%            || Publisher
+%                   <- mnesia:dirty_select(Table_Pubsub_State,
+%                          [{#pubsub_state_dev{
+%                                id      = {'$1', '_'},
+%                                nodeidx = NodeIdx,
+%                                itemids = '$2',
+%                               _       = '_'},
+%                          [{'=/=', '$2', []}],
+%                          ['$1']}])
+%            ]
+%           ),
+%        %
+%        xmlel_field_text_single(<<"pubsub#num_subscribers">>,
+%            <<"Number of subscribers to this node">>,
+%            list_to_binary(integer_to_list(length(
+%                mnesia:dirty_select(Table_Pubsub_State,
+%                    [{#pubsub_state_dev{
+%                          id            = {'$1', '_'},
+%                          nodeidx       = NodeIdx,
+%                          access        = '$2',
+%                          subscriptions = '$3',
+%                          _             = '_'},
+%                    [{'=/=', '$2', 'pending'},
+%                     {'=/=', '$3', []}],
+%                    ['$1']}])
+%            )))
+%           )
+        ]).
+
+%%
+-spec(iq_disco_items/9 ::
+(
+  Suffix      :: undefined | atom(),
+  Host        :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host :: exmpp_pubsub:host_pubsub(),
+  Privacy     :: boolean(),
+  Entity      :: xmpp_jid:usr_bare(),
+  Entity_Type :: 'local' | 'remote',
+  Plugin      :: exmpp_pubsub:plugin(),
+  NodeId      :: undefined | exmpp_pubsub:nodeId(),
+  Xmlels      :: [] | [Xmlel_Set::xmlel(),...])
+    -> {result, Xmlel_Query::xmlel()}
+    %%%
+%     | {error, 'feature-not-implemented', ?NS_DISCO_ITEMS}
+%     %
+%     | {error, 'item-not-found'}
+).
+
+iq_disco_items(Suffix, Host, Pubsub_Host, Privacy, Entity, _Entity_Type,
+  Plugin, NodeId, _Xmlels) ->
+    case lists:member(?NS_DISCO_ITEMS, Plugin:features()) of
+        true  -> disco_nodes(Privacy, NodeId, Suffix, Host, Pubsub_Host, Entity);
+        false -> {error, 'feature-not-implemented', ?NS_DISCO_ITEMS}
+    end.
+
+%%
+-spec(disco_nodes/6 ::
+(
+  Privacy     :: boolean(),
+  NodeId      :: undefined | exmpp_pubsub:nodeId(),
+  Suffix      :: undefined | atom(),
+  Host        :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host :: exmpp_pubsub:host_pubsub(),
+  Entity      :: xmpp_jid:usr_bare())
+    -> {result, Xmlel_Query::xmlel()}
+    %%%
+     | {error, 'item-not-found'}
+).
+
+disco_nodes(false, undefined, Suffix, _, Pubsub_Host, _) ->
+    {result,
+     exmpp_pubsub:xmlel_query('disco#items',
+         [exmpp_pubsub:xmlel_item('disco#items', NodeId, Pubsub_Host,
+              get_value(Node_Options, 'title', undefined))
+         || #pubsub_node_dev{id = {_, NodeId}, options = Node_Options}
+                <- mnesia:dirty_match_object(table('pubsub_node', Suffix),
+                       #pubsub_node_dev{
+                           id    = {Pubsub_Host, '_'},
+                           level = 1,
+                           _     = '_'
+                       })
+         ])};
+%%
+disco_nodes(true, undefined, Suffix, Host, Pubsub_Host, Entity) ->
+    {result,
+     exmpp_pubsub:xmlel_query('disco#items',
+         disco_nodes(
+             mnesia:dirty_match_object(table('pubsub_node', Suffix),
+                 #pubsub_node_dev{
+                     id = {Pubsub_Host, '_'},
+                     _  = '_'
+                 }),
+             Host, Entity, table('pubsub_state', Suffix), {[], [], []}))};
+%%
+disco_nodes(false, NodeId, Suffix, _Host, Pubsub_Host, _Entity) ->
+    Table_Pubsub_Node = table('pubsub_node', Suffix),
+    case mnesia:dirty_read(Table_Pubsub_Node, {Pubsub_Host, NodeId}) of
+        [#pubsub_node_dev{idx = NodeIdx, options = Node_Options}] ->
+            {result,
+             exmpp_pubsub:xmlel_query('disco#items',
+                case get_value(Node_Options, 'node_type') of
+                    'leaf' ->
+                        [exmpp_pubsub:xmlel_item('disco#items', ItemId,
+                             Pubsub_Host)
+                        || #pubsub_item_dev{id = {ItemId, _}}
+                               <- mnesia:dirty_index_match_object(
+                                      table('pubsub_item', Suffix),
+                                      #pubsub_item_dev{
+                                          id      = {'_', NodeIdx},
+                                          nodeidx = NodeIdx,
+                                           _      = '_'
+                                      },
+                                      nodeidx)
+                        ];
+                    'collection' ->
+                        lists:foldr(fun
+                            (_NodeId, Xmlels_Item) ->
+                                case
+                                    mnesia:dirty_read(Table_Pubsub_Node,
+                                        {Pubsub_Host, _NodeId})
+                                of
+                                    [#pubsub_node_dev{options = _Node_Options}] ->
+                                        [exmpp_pubsub:xmlel_item('disco#items',
+                                             _NodeId, Pubsub_Host,
+                                             get_value(_Node_Options, 'title',
+                                                 undefined))
+                                        |Xmlels_Item];
+                                    _ ->
+                                        Xmlels_Item
+                                end
+                        end, [], get_value(Node_Options, 'children', []))
+                end)};
+         _ ->
+            {error, 'item_not-found'}
+    end;
+%%
+disco_nodes(true, NodeId, Suffix, Host, Pubsub_Host, Entity) ->
+    Table_Pubsub_Node = table('pubsub_node', Suffix),
+    case mnesia:dirty_read(Table_Pubsub_Node, {Pubsub_Host, NodeId}) of
+        [#pubsub_node_dev{idx = NodeIdx, owners = Node_Owners,
+         options = Node_Options}] ->
+            case lists:member(Entity, Node_Owners) of
+                true ->
+                    {result,
+                     exmpp_pubsub:xmlel_query('disco#items',
+                        case get_value(Node_Options, 'node_type') of
+                            'leaf' ->
+                                disco_items(
+                                    mnesia:dirty_index_match_object(
+                                        table('pubsub_item', Suffix),
+                                        #pubsub_item_dev{
+                                            id      = {'_', NodeIdx},
+                                            nodeidx = NodeIdx,
+                                            _      = '_'
+                                        },
+                                        nodeidx),
+                                    Host, Pubsub_Host,
+                                    get_value(Node_Options, 'access_model'),
+                                    get_value(Node_Options, 'roster_groups_allowed', []),
+                                    Node_Owners,
+                                    Entity,
+                                    'owner',
+                                    undefined,
+                                    {[], [], []});
+                            'collection' ->
+                                disco_nodes(
+                                    lists:foldr(fun
+                                        (_NodeId, Pubsub_Nodes) ->
+                                        case
+                                            mnesia:dirty_read(Table_Pubsub_Node,
+                                                {Pubsub_Host, _NodeId})
+                                        of
+                                            [Pubsub_Node] ->
+                                                [Pubsub_Node | Pubsub_Nodes];
+                                            _ ->
+                                                Pubsub_Nodes
+                                        end
+                                    end, [], get_value(Node_Options, 'children', [])),
+                                    Host, Entity, table('pubsub_state', Suffix),
+                                    {[], [], []})
+                        end)};
+                false ->
+                    Node_Access_Model = get_value(Node_Options, 'access_model'),
+                    case
+                        mnesia:dirty_index_match_object(
+                            table('pubsub_state', Suffix),
+                            #pubsub_state_dev{
+                                id      = {Entity, NodeIdx},
+                                nodeidx = NodeIdx,
+                                _       = '_'
+                            },
+                            nodeidx)
+                    of
+                        %%
+                        [#pubsub_state_dev{affiliation = Affiliation}]
+                          when    Node_Access_Model == 'open'
+                          andalso (Affiliation == 'member'
+                                       orelse
+                                   Affiliation == 'none'
+                                       orelse
+                                   Affiliation == 'publisher') ->
+                            {result,
+                             exmpp_pubsub:xmlel_query('disco#items',
+                            case get_value(Node_Options, 'node_type') of
+                                'leaf' ->
+                                    disco_items(
+                                        mnesia:dirty_index_match_object(
+                                            table('pubsub_item', Suffix),
+                                            #pubsub_item_dev{
+                                                id      = {'_', NodeIdx},
+                                                nodeidx = NodeIdx,
+                                                _      = '_'
+                                            },
+                                            nodeidx),
+                                        Host, Pubsub_Host,
+                                        get_value(Node_Options, 'access_model'),
+                                        get_value(Node_Options,
+                                            'roster_groups_allowed', []),
+                                        Node_Owners,
+                                        Entity,
+                                        'owner',
+                                        undefined,
+                                        {[], [], []});
+                                'collection' ->
+                                    disco_nodes(
+                                        lists:foldr(fun
+                                            (_NodeId, Pubsub_Nodes) ->
+                                            case
+                                                mnesia:dirty_read(Table_Pubsub_Node,
+                                                    {Pubsub_Host, _NodeId})
+                                            of
+                                                [Pubsub_Node] ->
+                                                    [Pubsub_Node | Pubsub_Nodes];
+                                                _ ->
+                                                    Pubsub_Nodes
+                                            end
+                                        end, [],
+                                            get_value(Node_Options, 'children', [])),
+                                        Host, Entity, table('pubsub_state', Suffix),
+                                        {[], [], []})
+                            end)};
+                        %%
+                        []
+                          when Node_Access_Model == 'open' ->
+                            {result,
+                             exmpp_pubsub:xmlel_query('disco#items',
+                            case get_value(Node_Options, 'node_type') of
+                                'leaf' ->
+                                    disco_items(
+                                        mnesia:dirty_index_match_object(
+                                            table('pubsub_item', Suffix),
+                                            #pubsub_item_dev{
+                                                id      = {'_', NodeIdx},
+                                                nodeidx = NodeIdx,
+                                                _      = '_'
+                                            },
+                                            nodeidx),
+                                        Host, Pubsub_Host,
+                                        get_value(Node_Options, 'access_model'),
+                                        get_value(Node_Options,
+                                            'roster_groups_allowed', []),
+                                        Node_Owners,
+                                        Entity,
+                                        'owner',
+                                        undefined,
+                                        {[], [], []});
+                                'collection' ->
+                                    disco_nodes(
+                                        lists:foldr(fun
+                                            (_NodeId, Pubsub_Nodes) ->
+                                            case
+                                                mnesia:dirty_read(Table_Pubsub_Node,
+                                                    {Pubsub_Host, _NodeId})
+                                            of
+                                                [Pubsub_Node] ->
+                                                    [Pubsub_Node | Pubsub_Nodes];
+                                                _ ->
+                                                    Pubsub_Nodes
+                                            end
+                                        end, [],
+                                            get_value(Node_Options, 'children', [])),
+                                        Host, Entity, table('pubsub_state', Suffix),
+                                        {[], [], []})
+                            end)};
+                        %%
+                        _
+                          when Node_Access_Model == 'open' ->
+                            {error, 'item-not-found'};
+                        %%
+                        [#pubsub_state_dev{affiliation = Affiliation, access = Access}]
+                          when Node_Access_Model == 'presence'
+                          andalso (Affiliation == 'member'
+                                       orelse
+                                   Affiliation == 'publisher'
+                                       orelse
+                                   Access      == 'presence'
+                                       orelse
+                                   Access      == 'roster') ->
+                            {result,
+                             exmpp_pubsub:xmlel_query('disco#items',
+                            case get_value(Node_Options, 'node_type') of
+                                'leaf' ->
+                                    disco_items(
+                                        mnesia:dirty_index_match_object(
+                                            table('pubsub_item', Suffix),
+                                            #pubsub_item_dev{
+                                                id      = {'_', NodeIdx},
+                                                nodeidx = NodeIdx,
+                                                _      = '_'
+                                            },
+                                            nodeidx),
+                                        Host, Pubsub_Host,
+                                        get_value(Node_Options, 'access_model'),
+                                        get_value(Node_Options,
+                                            'roster_groups_allowed', []),
+                                        Node_Owners,
+                                        Entity,
+                                        'owner',
+                                        undefined,
+                                        {[], [], []});
+                                'collection' ->
+                                    disco_nodes(
+                                        lists:foldr(fun
+                                            (_NodeId, Pubsub_Nodes) ->
+                                            case
+                                                mnesia:dirty_read(Table_Pubsub_Node,
+                                                    {Pubsub_Host, _NodeId})
+                                            of
+                                                [Pubsub_Node] ->
+                                                    [Pubsub_Node | Pubsub_Nodes];
+                                                _ ->
+                                                    Pubsub_Nodes
+                                            end
+                                        end, [],
+                                            get_value(Node_Options, 'children', [])),
+                                        Host, Entity, table('pubsub_state', Suffix),
+                                        {[], [], []})
+                            end)};
+                        %%
+                        [#pubsub_state_dev{affiliation = Affiliation}]
+                          when    Node_Access_Model == 'presence'
+                          andalso (Affiliation == 'outcast'
+                                       orelse
+                                   Affiliation == 'publish-only') ->
+                            {error, 'item-not-found'};
+                        %%
+                        _
+                          when    Node_Access_Model == 'presence' ->
+                            case
+                                is_contact_subscribed_to_node_owners(Host, Entity,
+                                    Node_Owners)
+                            of
+                                false ->
+                                    {error, 'item-not-found'};
+                                Node_Owner ->
+                                {result, exmpp_pubsub:xmlel_query('disco#items',
+                                case get_value(Node_Options, 'node_type') of
+                                    'leaf' ->
+                                        disco_items(
+                                            mnesia:dirty_index_match_object(
+                                                table('pubsub_item', Suffix),
+                                                #pubsub_item_dev{
+                                                    id      = {'_', NodeIdx},
+                                                    nodeidx = NodeIdx,
+                                                    _      = '_'
+                                                },
+                                                nodeidx),
+                                            Host, Pubsub_Host,
+                                            get_value(Node_Options, 'access_model'),
+                                            get_value(Node_Options,
+                                                'roster_groups_allowed', []),
+                                            Node_Owners,
+                                            Entity,
+                                            'owner',
+                                            undefined,
+                                            {[], [], []});
+                                    'collection' ->
+                                        disco_nodes(
+                                            lists:foldr(fun
+                                                (_NodeId, Pubsub_Nodes) ->
+                                                case
+                                                    mnesia:dirty_read(Table_Pubsub_Node,
+                                                        {Pubsub_Host, _NodeId})
+                                                of
+                                                    [Pubsub_Node] ->
+                                                        [Pubsub_Node | Pubsub_Nodes];
+                                                    _ ->
+                                                        Pubsub_Nodes
+                                                end
+                                            end, [],
+                                                get_value(Node_Options, 'children', [])),
+                                            Host, Entity, table('pubsub_state', Suffix),
+                                            {[], [Node_Owner], []})
+                                end)}
+                            end;
+                        %%
+                        [#pubsub_state_dev{affiliation = Affiliation, access = Access}]
+                          when Node_Access_Model == 'roster'
+                          andalso (Affiliation == 'member'
+                                       orelse
+                                   Affiliation == 'publisher'
+                                       orelse
+                                   (Access      == 'roster'
+                                        andalso
+                                    Affiliation == 'none')) ->
+                            {result,
+                             exmpp_pubsub:xmlel_query('disco#items',
+                            case get_value(Node_Options, 'node_type') of
+                                'leaf' ->
+                                    disco_items(
+                                        mnesia:dirty_index_match_object(
+                                            table('pubsub_item', Suffix),
+                                            #pubsub_item_dev{
+                                                id      = {'_', NodeIdx},
+                                                nodeidx = NodeIdx,
+                                                _      = '_'
+                                            },
+                                            nodeidx),
+                                        Host, Pubsub_Host,
+                                        get_value(Node_Options, 'access_model'),
+                                        get_value(Node_Options,
+                                            'roster_groups_allowed', []),
+                                        Node_Owners,
+                                        Entity,
+                                        'owner',
+                                        undefined,
+                                        {[], [], []});
+                                'collection' ->
+                                    disco_nodes(
+                                        lists:foldr(fun
+                                            (_NodeId, Pubsub_Nodes) ->
+                                            case
+                                                mnesia:dirty_read(Table_Pubsub_Node,
+                                                    {Pubsub_Host, _NodeId})
+                                            of
+                                                [Pubsub_Node] ->
+                                                    [Pubsub_Node | Pubsub_Nodes];
+                                                _ ->
+                                                    Pubsub_Nodes
+                                            end
+                                        end, [],
+                                            get_value(Node_Options, 'children', [])),
+                                        Host, Entity, table('pubsub_state', Suffix),
+                                        {[], [], []})
+                            end)};
+                        %%
+                        [#pubsub_state_dev{affiliation = Affiliation}]
+                          when    Node_Access_Model == 'roster'
+                          andalso (Affiliation == 'outcast'
+                                       orelse
+                                   Affiliation == 'publish-only') ->
+                            {error, 'item-not-found'};
+                        %%
+                        _
+                          when    Node_Access_Model == 'roster' ->
+                            Rosters_Groups_Allowed = get_value(Node_Options,
+                                'roster_groups_allowed', []),
+                            case
+                                is_contact_in_allowed_roster_groups(Entity,
+                                    Rosters_Groups_Allowed)
+                            of
+                                false ->
+                                    {error, 'item-not-found'};
+                                {Node_Owner, Roster_Group} ->
+                                    {result,
+                                     exmpp_pubsub:xmlel_query('disco#items',
+                                    case get_value(Node_Options, 'node_type') of
+                                        'leaf' ->
+                                            disco_items(
+                                                mnesia:dirty_index_match_object(
+                                                    table('pubsub_item', Suffix),
+                                                    #pubsub_item_dev{
+                                                        id      = {'_', NodeIdx},
+                                                        nodeidx = NodeIdx,
+                                                        _      = '_'
+                                                    },
+                                                    nodeidx),
+                                                Host, Pubsub_Host,
+                                                get_value(Node_Options, 'access_model'),
+                                                Rosters_Groups_Allowed,
+                                                Node_Owners,
+                                                Entity,
+                                                'owner',
+                                                undefined,
+                                                {[], [], []});
+                                        'collection' ->
+                                            disco_nodes(
+                                                lists:foldr(fun
+                                                    (_NodeId, Pubsub_Nodes) ->
+                                                    case
+                                                        mnesia:dirty_read(
+                                                            Table_Pubsub_Node,
+                                                            {Pubsub_Host, _NodeId})
+                                                    of
+                                                        [Pubsub_Node] ->
+                                                            [Pubsub_Node | Pubsub_Nodes];
+                                                        _ ->
+                                                            Pubsub_Nodes
+                                                    end
+                                                end, [],
+                                                    get_value(Node_Options,
+                                                        'children', [])),
+                                                Host, Entity,
+                                                table('pubsub_state', Suffix),
+                                                {[], [], [{Node_Owner, [Roster_Group]}]})
+                                    end)}
+                            end;
+                        %%
+                        [#pubsub_state_dev{affiliation = Affiliation, access = Access}]
+                          when    Node_Access_Model == 'authorize'
+                          andalso ((Affiliation =/= 'publish-only'
+                                        andalso
+                                    Affiliation =/= 'outcast')
+                                    orelse
+                                  Access == 'authorize') ->
+                            {result,
+                             exmpp_pubsub:xmlel_query('disco#items',
+                            case get_value(Node_Options, 'node_type') of
+                                'leaf' ->
+                                    disco_items(
+                                        mnesia:dirty_index_match_object(
+                                            table('pubsub_item', Suffix),
+                                            #pubsub_item_dev{
+                                                id      = {'_', NodeIdx},
+                                                nodeidx = NodeIdx,
+                                                _      = '_'
+                                            },
+                                            nodeidx),
+                                        Host, Pubsub_Host,
+                                        get_value(Node_Options, 'access_model'),
+                                        get_value(Node_Options,
+                                            'roster_groups_allowed', []),
+                                        Node_Owners,
+                                        Entity,
+                                        'owner',
+                                        undefined,
+                                        {[], [], []});
+                                'collection' ->
+                                    disco_nodes(
+                                        lists:foldr(fun
+                                            (_NodeId, Pubsub_Nodes) ->
+                                            case
+                                                mnesia:dirty_read(Table_Pubsub_Node,
+                                                    {Pubsub_Host, _NodeId})
+                                            of
+                                                [Pubsub_Node] ->
+                                                    [Pubsub_Node | Pubsub_Nodes];
+                                                _ ->
+                                                    Pubsub_Nodes
+                                            end
+                                        end, [],
+                                            get_value(Node_Options, 'children', [])),
+                                        Host, Entity, table('pubsub_state', Suffix),
+                                        {[], [], []})
+                            end)};
+                        %%
+                        []
+                          when Node_Access_Model == 'authorize' ->
+                            {result,
+                             exmpp_pubsub:xmlel_query('disco#items',
+                            case get_value(Node_Options, 'node_type') of
+                                'leaf' ->
+                                    disco_items(
+                                        mnesia:dirty_index_match_object(
+                                            table('pubsub_item', Suffix),
+                                            #pubsub_item_dev{
+                                                id      = {'_', NodeIdx},
+                                                nodeidx = NodeIdx,
+                                                _      = '_'
+                                            },
+                                            nodeidx),
+                                        Host, Pubsub_Host,
+                                        get_value(Node_Options, 'access_model'),
+                                        get_value(Node_Options,
+                                            'roster_groups_allowed', []),
+                                        Node_Owners,
+                                        Entity,
+                                        'owner',
+                                        undefined,
+                                        {[], [], []});
+                                'collection' ->
+                                    disco_nodes(
+                                        lists:foldr(fun
+                                            (_NodeId, Pubsub_Nodes) ->
+                                            case
+                                                mnesia:dirty_read(Table_Pubsub_Node,
+                                                    {Pubsub_Host, _NodeId})
+                                            of
+                                                [Pubsub_Node] ->
+                                                    [Pubsub_Node | Pubsub_Nodes];
+                                                _ ->
+                                                    Pubsub_Nodes
+                                            end
+                                        end, [],
+                                            get_value(Node_Options, 'children', [])),
+                                        Host, Entity, table('pubsub_state', Suffix),
+                                        {[], [], []})
+                            end)};
+                        %%
+                        _
+                          when Node_Access_Model == 'authorize' ->
+                            {error, 'item-not-found'};
+                        %%
+                        [#pubsub_state_dev{affiliation = Affiliation, access = Access}]
+                          when    Node_Access_Model == 'whitelist'
+                          andalso (Access == 'whitelist'
+                                       orelse
+                                  (Affiliation =/= 'none'
+                                       andalso
+                                   Affiliation =/= 'outcast'
+                                       andalso
+                                   Affiliation =/= 'publish-only')) ->
+                            {result,
+                             exmpp_pubsub:xmlel_query('disco#items',
+                            case get_value(Node_Options, 'node_type') of
+                                'leaf' ->
+                                    disco_items(
+                                        mnesia:dirty_index_match_object(
+                                            table('pubsub_item', Suffix),
+                                            #pubsub_item_dev{
+                                                id      = {'_', NodeIdx},
+                                                nodeidx = NodeIdx,
+                                                _      = '_'
+                                            },
+                                            nodeidx),
+                                        Host, Pubsub_Host,
+                                        get_value(Node_Options, 'access_model'),
+                                        get_value(Node_Options,
+                                            'roster_groups_allowed', []),
+                                        Node_Owners,
+                                        Entity,
+                                        'owner',
+                                        undefined,
+                                        {[], [], []});
+                                'collection' ->
+                                    disco_nodes(
+                                        lists:foldr(fun
+                                            (_NodeId, Pubsub_Nodes) ->
+                                                case
+                                                    mnesia:dirty_read(
+                                                        Table_Pubsub_Node,
+                                                    {Pubsub_Host, _NodeId})
+                                                of
+                                                    [Pubsub_Node] ->
+                                                        [Pubsub_Node | Pubsub_Nodes];
+                                                    _ ->
+                                                        Pubsub_Nodes
+                                                end
+                                        end, [],
+                                            get_value(Node_Options, 'children', [])),
+                                        Host, Entity, table('pubsub_state', Suffix),
+                                        {[], [], []})
+                            end)};
+                        %%
+                        _ ->
+                            {error, 'item-not-found'}
+                    end
+                end;
+         _ ->
+            {error, 'item_not-found'}
+    end.
+
+%%
+-spec(disco_nodes/5 ::
+(
+  Pubsub_Nodes       :: [] | mod_pubsub_dev:pubsub_nodes(),
+  Host               :: xmpp_jid:raw_jid_component_bare(),
+  Entity             :: xmpp_jid:usr_bare(),
+  Table_Pubsub_State :: atom(),
+  Cache                  :: {
+      Xmlels_Items   :: [Xmlel_Item::xmlel()],
+      Presence_Cache :: [Entity::xmpp_jid:usr_bare()],
+      Groups_Cache   :: [{Entity::xmpp_jid:usr_bare(), Groups::[Group::binary(),...]}]
+  })
+    -> Xmlels_Items::[Xmlel_Item::xmlel()]
+).
+
+disco_nodes([] = _Pubsub_Nodes, _Host, _Entity, _Table_Pubsub_State,
+  {Xmlels_Item, _Presence_Cache, _Groups_Cache}) ->
+    Xmlels_Item;
+%%
+disco_nodes([#pubsub_node_dev{id = {Pubsub_Host, NodeId},
+  idx = NodeIdx, owners = Node_Owners, options = Node_Options} | Pubsub_Nodes],
+  Host, Entity, Table_Pubsub_State,
+  {Xmlels_Item, Presence_Cache, Groups_Cache}) ->
+    disco_nodes(Pubsub_Nodes, Host, Entity, Table_Pubsub_State,
+        case lists:member(Entity, Node_Owners) of
+            true ->
+                {[exmpp_pubsub:xmlel_item('disco#items', NodeId, Pubsub_Host,
+                      get_value(Node_Options, 'title', undefined))
+                 |Xmlels_Item],
+                 Presence_Cache, Groups_Cache};
+            false ->
+                Node_Access_Model = get_value(Node_Options, 'access_model'),
+                case
+                    mnesia:dirty_index_match_object(Table_Pubsub_State,
+                       #pubsub_state_dev{
+                           id      = {Entity, NodeIdx},
+                           nodeidx = NodeIdx,
+                           _       = '_'
+                        },
+                        nodeidx)
+                of
+                    %%
+                    [#pubsub_state_dev{affiliation = Affiliation}]
+                      when    Node_Access_Model == 'open'
+                      andalso (Affiliation == 'member'
+                                   orelse
+                               Affiliation == 'none'
+                                   orelse
+                               Affiliation == 'publisher') ->
+                        {[exmpp_pubsub:xmlel_item('disco#items', NodeId,
+                              Pubsub_Host,
+                              get_value(Node_Options, 'title', undefined))
+                         |Xmlels_Item],
+                         Presence_Cache, Groups_Cache};
+                    %%
+                    []
+                      when Node_Access_Model == 'open' ->
+                        {[exmpp_pubsub:xmlel_item('disco#items', NodeId,
+                              Pubsub_Host,
+                              get_value(Node_Options, 'title', undefined))
+                         |Xmlels_Item],
+                         Presence_Cache, Groups_Cache};
+                    %%
+                    _
+                      when Node_Access_Model == 'open' ->
+                        {Xmlels_Item, Presence_Cache, Groups_Cache};
+                    %%
+                    [#pubsub_state_dev{affiliation = Affiliation, access = Access}]
+                      when Node_Access_Model == 'presence'
+                      andalso (Affiliation == 'member'
+                                   orelse
+                               Affiliation == 'publisher'
+                                   orelse
+                               Access      == 'presence'
+                                   orelse
+                               Access      == 'roster') ->
+                        {[exmpp_pubsub:xmlel_item('disco#items', NodeId, Pubsub_Host,
+                              get_value(Node_Options, 'title', undefined))
+                         |Xmlels_Item],
+                          Presence_Cache, Groups_Cache};
+                    %%
+                    [#pubsub_state_dev{affiliation = Affiliation}]
+                      when    Node_Access_Model == 'presence'
+                      andalso (Affiliation == 'outcast'
+                                   orelse
+                               Affiliation == 'publish-only') ->
+                        {Xmlels_Item, Presence_Cache, Groups_Cache};
+                    %%
+                    _
+                      when    Node_Access_Model == 'presence'
+                      andalso Presence_Cache    == [] ->
+                        case
+                            is_contact_subscribed_to_node_owners(Host, Entity,
+                                Node_Owners)
+                        of
+                            false ->
+                                {Xmlels_Item, Presence_Cache, Groups_Cache};
+                            Node_Owner ->
+                                {[exmpp_pubsub:xmlel_item('disco#items', NodeId,
+                                      Pubsub_Host,
+                                  get_value(Node_Options, 'title', undefined))
+                                 |Xmlels_Item],
+                                 [Node_Owner | Presence_Cache], Groups_Cache}
+                        end;
+                    %%
+                    _
+                      when Node_Access_Model == 'presence' ->
+                        case presence_cache(Presence_Cache, Node_Owners) of
+                            true ->
+                                {[exmpp_pubsub:xmlel_item('disco#items', NodeId,
+                                      Pubsub_Host,
+                                  get_value(Node_Options, 'title', undefined))
+                                 |Xmlels_Item],
+                                 Presence_Cache, Groups_Cache};
+                            false ->
+                                case
+                                    is_contact_subscribed_to_node_owners(Host,
+                                        Entity, Node_Owners)
+                                of
+                                    false ->
+                                        {Xmlels_Item, Presence_Cache, Groups_Cache};
+                                    Node_Owner ->
+                                        {[exmpp_pubsub:xmlel_item('disco#items',
+                                              NodeId, Pubsub_Host,
+                                          get_value(Node_Options, 'title', undefined))
+                                         |Xmlels_Item],
+                                         [Node_Owner | Presence_Cache], Groups_Cache}
+                                end
+                        end;
+                    %%
+                    [#pubsub_state_dev{affiliation = Affiliation, access = Access}]
+                      when Node_Access_Model == 'roster'
+                      andalso (Affiliation == 'member'
+                                   orelse
+                               Affiliation == 'publisher'
+                                   orelse
+                               (Access      == 'roster'
+                                    andalso
+                                Affiliation == 'none')) ->
+                        {[exmpp_pubsub:xmlel_item('disco#items', NodeId, Pubsub_Host,
+                              get_value(Node_Options, 'title', undefined))
+                         |Xmlels_Item],
+                          Presence_Cache, Groups_Cache};
+                    %%
+                    [#pubsub_state_dev{affiliation = Affiliation}]
+                      when    Node_Access_Model == 'roster'
+                      andalso (Affiliation == 'outcast'
+                                   orelse
+                               Affiliation == 'publish-only') ->
+                        {Xmlels_Item, Presence_Cache, Groups_Cache};
+                    %%
+                    _
+                      when    Node_Access_Model == 'roster'
+                      andalso Groups_Cache      == [] ->
+                        case
+                            is_contact_in_allowed_roster_groups(Entity,
+                                get_value(Node_Options, 'roster_groups_allowed'))
+                        of
+                            false ->
+                                {Xmlels_Item, Presence_Cache, Groups_Cache};
+                            {Node_Owner, Roster_Group} ->
+                                {[exmpp_pubsub:xmlel_item('disco#items', NodeId,
+                                      Pubsub_Host,
+                                      get_value(Node_Options, 'title', undefined))
+                                 |Xmlels_Item],
+                                  Presence_Cache,
+                                  [{Node_Owner, [Roster_Group]} | Groups_Cache]}
+                        end;
+                    %%
+                    _
+                      when Node_Access_Model == 'roster' ->
+                        Rosters_Groups_Allowed = get_value(Node_Options,
+                            'roster_groups_allowed'),
+                        case groups_cache(Groups_Cache, Rosters_Groups_Allowed) of
+                            true ->
+                                {[exmpp_pubsub:xmlel_item('disco#items', NodeId,
+                                      Pubsub_Host,
+                                  get_value(Node_Options, 'title', undefined))
+                                 |Xmlels_Item],
+                                 Presence_Cache, Groups_Cache};
+                            false ->
+                                case
+                                    is_contact_in_allowed_roster_groups(Entity,
+                                        Rosters_Groups_Allowed)
+                                of
+                                    false ->
+                                        {Xmlels_Item, Presence_Cache, Groups_Cache};
+                                    {Node_Owner, Roster_Group} ->
+                                        {[exmpp_pubsub:xmlel_item('disco#items',
+                                              NodeId, Pubsub_Host,
+                                              get_value(Node_Options, 'title',
+                                                  undefined))
+                                         |Xmlels_Item],
+                                          Presence_Cache,
+                                          case
+                                              lists:keyfind(Node_Owner, 1,
+                                                  Groups_Cache)
+                                          of
+                                              {_, Groups} ->
+                                                  lists:keyreplace(Node_Owner, 1,
+                                                      Groups_Cache,
+                                                      {Node_Owner,
+                                                       [Roster_Group | Groups]});
+                                              false ->
+                                                  [{Node_Owner, [Roster_Group]}
+                                                  | Groups_Cache]
+                                          end}
+                                end
+                        end;
+                    %%
+                    [#pubsub_state_dev{affiliation = Affiliation, access = Access}]
+                      when    Node_Access_Model == 'authorize'
+                      andalso ((Affiliation =/= 'publish-only'
+                                    andalso
+                                Affiliation =/= 'outcast')
+                                orelse
+                              Access == 'authorize') ->
+                        {[exmpp_pubsub:xmlel_item('disco#items', NodeId,
+                              Pubsub_Host,
+                              get_value(Node_Options, 'title', undefined))
+                         |Xmlels_Item],
+                         Presence_Cache, Groups_Cache};
+                    %%
+                    []
+                      when Node_Access_Model == 'authorize' ->
+                        {[exmpp_pubsub:xmlel_item('disco#items', NodeId,
+                              Pubsub_Host,
+                              get_value(Node_Options, 'title', undefined))
+                         |Xmlels_Item],
+                         Presence_Cache, Groups_Cache};
+                    %%
+                    _
+                      when Node_Access_Model == 'authorize' ->
+                        {Xmlels_Item, Presence_Cache, Groups_Cache};
+                    %%
+                    [#pubsub_state_dev{affiliation = Affiliation, access = Access}]
+                      when    Node_Access_Model == 'whitelist'
+                      andalso (Access == 'whitelist'
+                                   orelse
+                              (Affiliation =/= 'none'
+                                   andalso
+                               Affiliation =/= 'outcast'
+                                   andalso
+                               Affiliation =/= 'publish-only')) ->
+                        {[exmpp_pubsub:xmlel_item('disco#items', NodeId,
+                              Pubsub_Host,
+                              get_value(Node_Options, 'title', undefined))
+                         |Xmlels_Item],
+                         Presence_Cache, Groups_Cache};
+                    %%
+                    _ ->
+                        {Xmlels_Item, Presence_Cache, Groups_Cache}
+            end
+    end).
+
+%%
+-spec(disco_items/10 ::
+(
+  Pubsub_Items           :: [] | mod_pubsub_dev:pubsub_items(),
+  Host                   :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host            :: exmpp_pubsub:host_pubsub(),
+  Node_Access_Model      :: pubsub_options:access_model(),
+  Rosters_Groups_Allowed :: pubsub_options:rosters_groups_allowed(),
+  Node_Owners            :: mod_pubsub_dev:node_owners(),
+  Entity                 :: xmpp_jid:usr_bare(),
+  Affiliation            :: 'member' | 'none' | 'owner' | 'publisher',
+  Access                 :: undefined|'authorize'|'presence'|'roster'|'whitelist',
+  Cache                  :: {
+      Xmlels_Items   :: [Xmlel_Item::xmlel()],
+      Presence_Cache :: [Entity::xmpp_jid:usr_bare()],
+      Groups_Cache   :: [{Entity::xmpp_jid:usr_bare(), Groups::[Group::binary(),...]}]
+  })
+    -> Xmlels_Items::[Xmlel_Item::xmlel()]
+).
+
+disco_items([] = _Pubsub_Items, _Host, _Pubsub_Host, _Node_Access_Model,
+  _Rosters_Groups_Allowed, _Node_Owners, _Entity, _Affiliation, _Access,
+  {Xmlels_Items, _, _}) ->
+    Xmlels_Items;
+%%
+disco_items([#pubsub_item_dev{id = {ItemId, _}, options = Item_Options} | Pubsub_Items],
+  Host, Pubsub_Host, Node_Access_Model, Rosters_Groups_Allowed, Node_Owners, Entity,
+  Affiliation, Access,
+  {Xmlels_Item, Presence_Cache, Groups_Cache})
+  when   Item_Options == []
+  orelse Affiliation == 'owner'
+  orelse Affiliation == 'publisher' ->
+    disco_items(Pubsub_Items, Host, Pubsub_Host, Node_Access_Model,
+        Rosters_Groups_Allowed, Node_Owners, Entity, Affiliation, Access,
+        {[exmpp_pubsub:xmlel_item('disco#items', ItemId, Pubsub_Host)
+         | Xmlels_Item], Presence_Cache, Groups_Cache});
+%%
+disco_items([#pubsub_item_dev{id = {ItemId, _}, options = Item_Options} | Pubsub_Items],
+  Host, Pubsub_Host, Node_Access_Model, Rosters_Groups_Allowed, Node_Owners, Entity,
+  Affiliation, Access,
+  {Xmlels_Item, Presence_Cache, Groups_Cache}) ->
+    disco_items(Pubsub_Items, Host, Pubsub_Host, Node_Access_Model,
+        Rosters_Groups_Allowed, Node_Owners, Entity, Affiliation, Access,
+        case get_value(Item_Options, 'access_model') of
+            Item_Access_Model
+              when   Item_Access_Model == 'none'
+              orelse Item_Access_Model == 'open'
+              orelse (Item_Access_Model =/= 'roster'
+                           andalso
+                      Item_Access_Model == Node_Access_Model)
+              orelse (Item_Access_Model == 'presence'
+                           andalso
+                      (Node_Access_Model == 'roster'
+                              orelse
+                       Access == 'presence'
+                              orelse
+                       Access == 'roster'))
+              orelse Item_Access_Model == 'authorize'
+              orelse Item_Access_Model == 'whitelist' ->
+                {[exmpp_pubsub:xmlel_item('disco#items', ItemId, Pubsub_Host)
+                 | Xmlels_Item], Presence_Cache, Groups_Cache};
+            %%
+            'presence'
+              when   Access == 'presence'
+              orelse Access == 'roster' ->
+                {[exmpp_pubsub:xmlel_item('disco#items', ItemId, Pubsub_Host)
+                 | Xmlels_Item], Presence_Cache, Groups_Cache};
+            'presence'
+              when Presence_Cache == [] ->
+                case
+                    is_contact_subscribed_to_node_owners(Host, Entity, Node_Owners)
+                of
+                    false ->
+                        {Xmlels_Item, Presence_Cache, Groups_Cache};
+                    Node_Owner ->
+                        {[exmpp_pubsub:xmlel_item('disco#items', ItemId, Pubsub_Host)
+                         |Xmlels_Item],
+                         [Node_Owner | Presence_Cache], Groups_Cache}
+                end;
+            'presence' ->
+                case presence_cache(Presence_Cache, Node_Owners) of
+                    true ->
+                        {[exmpp_pubsub:xmlel_item('disco#items', ItemId, Pubsub_Host)
+                         |Xmlels_Item],
+                         Presence_Cache, Groups_Cache};
+                    false ->
+                        case
+                            is_contact_subscribed_to_node_owners(Host, Entity,
+                                Node_Owners)
+                        of
+                            false ->
+                                {Xmlels_Item, Presence_Cache, Groups_Cache};
+                            Node_Owner ->
+                                {[exmpp_pubsub:xmlel_item('disco#items', ItemId,
+                                      Pubsub_Host)
+                                 |Xmlels_Item],
+                                 [Node_Owner | Presence_Cache], Groups_Cache}
+                        end
+                end;
+            'roster'
+              when Rosters_Groups_Allowed == [] ->
+                case get_value(Item_Options, 'roster_groups_allowed') of
+                    Item_Roster_Groups_Allowed
+                      when   Item_Roster_Groups_Allowed == 'none'
+                      orelse Item_Roster_Groups_Allowed == [] ->
+                        {Xmlels_Item, Presence_Cache, Groups_Cache};
+                    Item_Roster_Groups_Allowed ->
+                        case
+                            groups_cache(Groups_Cache, Item_Roster_Groups_Allowed)
+                       of
+                            true ->
+                                {[exmpp_pubsub:xmlel_item('disco#items', ItemId,
+                                      Pubsub_Host)
+                                 |Xmlels_Item],
+                                 Presence_Cache, Groups_Cache};
+                            false ->
+                                case
+                                    is_contact_in_allowed_roster_groups(Entity,
+                                        Item_Roster_Groups_Allowed)
+                                of
+                                    false ->
+                                        {Xmlels_Item, Presence_Cache, Groups_Cache};
+                                    {Node_Owner, Roster_Group} ->
+                                        {[exmpp_pubsub:xmlel_item('disco#items',
+                                              ItemId, Pubsub_Host)
+                                         |Xmlels_Item],
+                                          Presence_Cache,
+                                          case
+                                              lists:keyfind(Node_Owner, 1,
+                                                  Groups_Cache)
+                                          of
+                                              {_, Groups} ->
+                                                  lists:keyreplace(Node_Owner, 1,
+                                                      Groups_Cache,
+                                                      {Node_Owner,
+                                                       [Roster_Group | Groups]});
+                                              false ->
+                                                  [{Node_Owner, [Roster_Group]}
+                                                  | Groups_Cache]
+                                          end}
+                                end
+                        end
+                end;
+            'roster' ->
+                case get_value(Item_Options, 'roster_groups_allowed') of
+                    Item_Rosters_Groups_Allowed
+                      when   Item_Rosters_Groups_Allowed == 'none'
+                      orelse Item_Rosters_Groups_Allowed == [] ->
+                        case
+                            groups_cache(Groups_Cache, Rosters_Groups_Allowed)
+                        of
+                            true ->
+                                {[exmpp_pubsub:xmlel_item('disco#items', ItemId,
+                                      Pubsub_Host)
+                                 |Xmlels_Item],
+                                 Presence_Cache, Groups_Cache};
+                            false ->
+                                case
+                                    is_contact_in_allowed_roster_groups(Entity,
+                                        Rosters_Groups_Allowed)
+                                of
+                                    false ->
+                                        {Xmlels_Item, Presence_Cache, Groups_Cache};
+                                    {Node_Owner, Roster_Group} ->
+                                        {[exmpp_pubsub:xmlel_item('disco#items',
+                                              ItemId, Pubsub_Host)
+                                         |Xmlels_Item],
+                                          Presence_Cache,
+                                          case
+                                              lists:keyfind(Node_Owner, 1,
+                                                  Groups_Cache)
+                                          of
+                                              {_, Groups} ->
+                                                  lists:keyreplace(Node_Owner, 1,
+                                                      Groups_Cache,
+                                                      {Node_Owner,
+                                                       [Roster_Group | Groups]});
+                                              false ->
+                                                  [{Node_Owner, [Roster_Group]}
+                                                  | Groups_Cache]
+                                          end}
+                                end
+                        end;
+                    Item_Rosters_Groups_Allowed ->
+                        case
+                            groups_cache(Groups_Cache, Item_Rosters_Groups_Allowed)
+                        of
+                            true ->
+                                {[exmpp_pubsub:xmlel_item('disco#items', ItemId,
+                                      Pubsub_Host)
+                                 |Xmlels_Item],
+                                 Presence_Cache, Groups_Cache};
+                            false ->
+                                case
+                                    is_contact_in_allowed_roster_groups(Entity,
+                                        Item_Rosters_Groups_Allowed)
+                                of
+                                    false ->
+                                        {Xmlels_Item, Presence_Cache, Groups_Cache};
+                                    {Node_Owner, Roster_Group} ->
+                                        {[exmpp_pubsub:xmlel_item('disco#items',
+                                              ItemId, Pubsub_Host)
+                                         |Xmlels_Item],
+                                          Presence_Cache,
+                                          case
+                                              lists:keyfind(Node_Owner, 1,
+                                                  Groups_Cache)
+                                          of
+                                              {_, Groups} ->
+                                                  lists:keyreplace(Node_Owner, 1,
+                                                      Groups_Cache,
+                                                      {Node_Owner,
+                                                       [Roster_Group | Groups]});
+                                              false ->
+                                                  [{Node_Owner, [Roster_Group]}
+                                                  | Groups_Cache]
+                                          end}
+                                end
+                        end
+                end;
+            _ ->
+                {Xmlels_Item, Presence_Cache, Groups_Cache}
+        end).
+
+
+%%
+-spec(presence_cache/2 ::
+(
+  Presence_Cache :: [Entity::xmpp_jid:usr_bare()],
+  Node_Owners    :: [] | [Entity::xmpp_jid:usr_bare(),...])
+    -> Presence_Cache::boolean()
+).
+
+presence_cache([], _) ->
+    false;
+%%
+presence_cache([Entity | Presence_Cache], Node_Owners) ->
+    case lists:member(Entity, Node_Owners) of
+        true  -> true;
+        false -> presence_cache(Presence_Cache, Node_Owners)
+    end.
+
+%%
+-spec(groups_cache/2 ::
+(
+  Groups_Cache   :: [Group_Cache :: {
+                         Entity::xmpp_jid:usr_bare(),
+                         Groups::[Group::binary(),...]
+                     }],
+  Rosters_Groups :: [Roster_Groups :: {
+                         Entity::xmpp_jid:usr_bare(),
+                         Groups::[Group::binary(),...]
+                     },...])
+    -> Groups_Cache::boolean()
+).
+
+groups_cache([], _) ->
+    false;
+%%
+groups_cache([{Entity, Groups} | Groups_Cache], Rosters_Groups) ->
+    case lists:keyfind(Entity, 1, Rosters_Groups) of
+        {_, Roster_Groups} -> group_cache(Groups, Roster_Groups);
+        false              -> groups_cache(Groups_Cache, Rosters_Groups)
+    end.
+
+%%
+-spec(group_cache/2 ::
+(
+  Groups        :: [] | [Group::binary(),...],
+  Roster_Groups :: [Group::binary(),...])
+    -> Group_Cache::boolean()
+).
+
+group_cache([], _) ->
+    false;
+%%
+group_cache([Group | Groups], Roster_Groups) ->
+    case lists:member(Group, Roster_Groups) of
+        true  -> true;
+        false -> group_cache(Groups, Roster_Groups)
+    end.
diff --git a/src/mod_pubsub_ng/pubsub_groups.erl b/src/mod_pubsub_ng/pubsub_groups.erl
new file mode 100644
index 000000000..c0ff2e96a
--- /dev/null
+++ b/src/mod_pubsub_ng/pubsub_groups.erl
@@ -0,0 +1,904 @@
+%%% ====================================================================
+%%% ``The contents of this file are subject to the Erlang Public License,
+%%% Version 1.1, (the "License"); you may not use this file except in
+%%% compliance with the License. You should have received a copy of the
+%%% Erlang Public License along with this software. If not, it can be
+%%% retrieved via the world wide web at http://www.erlang.org/.
+%%% 
+%%% Software distributed under the License is distributed on an "AS IS"
+%%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%%% the License for the specific language governing rights and limitations
+%%% under the License.
+%%% 
+%%% The Initial Developer of the Original Code is ProcessOne.
+%%% Portions created by ProcessOne are Copyright 2006-2011, ProcessOne
+%%% All Rights Reserved.''
+%%% This software is copyright 2006-2011, ProcessOne.
+%%%
+%%% @copyright 2006-2011 ProcessOne
+%%% @author Karim Gemayel <karim.gemayel@process-one.net>
+%%%   [http://www.process-one.net/]
+%%% @version {@vsn}, {@date} {@time}
+%%% @end
+%%% ====================================================================
+
+%%% @headerfile "pubsub_dev.hrl"
+
+-module(pubsub_groups).
+-author('karim.gemayel@process-one.net').
+
+-compile(export_all).
+
+-include("pubsub_dev.hrl").
+
+-import(pubsub_tools,
+[
+  get_option/2,
+  get_option/3,
+  get_value/2,
+  get_value/3,
+  set_value/3,
+  %%
+  check_acces_model/3,
+  check_acces_model/7,
+  check_publish_model/3,
+  get_entity_roster/1,
+  is_contact_subscribed_to_node_owners/3,
+  is_contact_in_allowed_roster_groups/2,
+  has_subscriptions/1,
+  get_resources/2,
+  get_resources_show/2,
+  rosters_groups_allowed_cache/2
+]).
+
+-import(pubsub_db_mnesia,
+[
+  table/2
+]).
+
+
+-type(group() :: binary()).
+
+-type(node_group() :: group()).
+
+-type(roster_group() :: group()).
+
+-type(node_groups() :: [Node_Group::node_group(),...]).
+
+-type(roster_groups() :: [Roster_Group::roster_group(),...]).
+
+-type(nodeIdxs() :: [NodeIdx::exmpp_pubsub:nodeIdx(),...]).
+
+-type(n0de()
+  :: {NodeIdx :: exmpp_pubsub:nodeIdx(),
+      Groups  :: node_groups()}
+).
+
+-type(n0des() :: [Node::n0de(),...]).
+
+-type(subscription()
+  :: {NodeIdx :: exmpp_pubsub:nodeIdx(),
+      Groups  :: roster_groups()}
+).
+
+-type(subscriptions() :: [Subscription::subscription(),...]).
+
+-type(contact()
+  :: {Entity        :: xmpp_jid:usr_bare(),
+      Subscriptions :: subscriptions()}
+).
+
+-type(contacts() :: [Contact::contact(),...]).
+
+
+-record(pubsub_groups,
+{
+  owner         :: xmpp_jid:usr_bare(),
+  nodes    = [] :: n0des(),
+  contacts = [] :: [] | contacts()
+}).
+
+
+create_table_pubsub_groups(Suffix) ->
+    mnesia:create_table(table('pubsub_groups', Suffix),
+        [{type, set},
+         {disc_copies, [node()]},
+         {record_name, pubsub_groups},
+         {attributes, record_info(fields, pubsub_groups)}]).
+
+
+
+%%
+-spec(register_groups/4 ::
+(
+  Suffix  :: atom(),
+  NodeIdx :: exmpp_pubsub:nodeIdx(),
+  Owner   :: xmpp_jid:usr_bare(),
+  Groups  :: [] | node_groups())
+    -> undefined
+     %
+     | {Subscribers   :: [Entity::xmpp_jid:usr_bare()],
+        Unsubscribers :: [Entity::xmpp_jid:usr_bare()]}
+).
+
+register_groups(Suffix, NodeIdx, Owner, [] = _Groups) ->
+    case
+        mnesia:read(Table_Pubsub_Groups = table('pubsub_groups', 'dev'),
+            Owner, write)
+    of
+        %%
+        [] ->
+            undefined;
+        %%
+        [#pubsub_groups{nodes = [{NodeIdx, _Node_Groups}]} = Pubsub_Groups] ->
+            mnesia:delete_object(Table_Pubsub_Groups, Pubsub_Groups, write),
+            %
+            {_Subscribers   = [],
+             _Unsubscribers = lists:foldl(fun
+                ({Entity, Subscriptions}, Unsubscribers) ->
+                    case lists:keymember(NodeIdx, 1, Subscriptions) of
+                        true  -> [Entity | Unsubscribers];
+                        false -> Unsubscribers
+                    end
+                %
+             end, [], Pubsub_Groups#pubsub_groups.contacts)};
+        %%
+        [Pubsub_Groups] ->
+            case lists:keyfind(NodeIdx, 1, Pubsub_Groups#pubsub_groups.nodes) of
+                {_NodeIdx, Node_Groups} ->
+                    {Contacts, Unsubscribers} = subscriptions1(NodeIdx,
+                        Pubsub_Groups#pubsub_groups.contacts),
+                    %
+                    mnesia:write(Table_Pubsub_Groups,
+                        Pubsub_Groups#pubsub_groups{
+                            contacts = Contacts
+                        },
+                        write),
+                    %
+                    {_Subscribers   = [],
+                     _Unsubscribers = Unsubscribers};
+                false ->
+                    undefined
+            end
+    end;
+%%
+register_groups(Suffix, NodeIdx, Owner, Groups) ->
+    case
+        mnesia:read(Table_Pubsub_Groups = table('pubsub_groups', 'dev'), Owner,
+            write)
+    of
+        [] ->
+            {Contacts, Subscribers} = subscriptions2(NodeIdx, Owner, Groups),
+            %
+            mnesia:write(Table_Pubsub_Groups,
+                #pubsub_groups{
+                    owner    = Owner,
+                    nodes    = [{NodeIdx, Groups}],
+                    contacts = Contacts
+                },
+                write),
+            %
+            {_Subscribers   = Subscribers,
+             _Unsubscribers = []};
+        [Pubsub_Groups] ->
+            case lists:keyfind(NodeIdx, 1, Pubsub_Groups#pubsub_groups.nodes) of
+                {_NodeIdx, Node_Groups} ->
+                    case diff_groups(Groups, Node_Groups) of
+                        %%
+                        {[] = _New_Groups, [] = _Old_Groups} ->
+                            {_Subscribers   = [],
+                             _Unsubscribers = []};
+                        %%
+                        {[] = _New_Groups, Old_Groups} ->
+                            {Contacts, Unsubscribers}
+                                = subscriptions3(NodeIdx, Old_Groups,
+                                    Pubsub_Groups#pubsub_groups.contacts),
+                            %
+                            mnesia:write(Table_Pubsub_Groups,
+                                Pubsub_Groups#pubsub_groups{
+                                    nodes    = lists:keyreplace(NodeIdx, 1,
+                                        Pubsub_Groups#pubsub_groups.nodes,
+                                        {NodeIdx, Groups}),
+                                    contacts = Contacts
+                                },
+                                write),
+                            %
+                            {_Subscribers   = [],
+                             _Unsubscribers = Unsubscribers};
+                        %%
+                        {_New_Groups, _Old_Groups}  ->
+                            {Contacts, Subscribers, Unsubscribers}
+                                = subscriptions4(NodeIdx, Owner, Node_Groups,
+                                    Pubsub_Groups#pubsub_groups.contacts),
+                            %
+                            mnesia:write(Table_Pubsub_Groups,
+                                Pubsub_Groups#pubsub_groups{
+                                    nodes    = lists:keyreplace(NodeIdx, 1,
+                                        Pubsub_Groups#pubsub_groups.nodes,
+                                            {NodeIdx, Node_Groups}),
+                                    contacts = Contacts
+                                },
+                                write),
+                            %
+                            {Subscribers    = Subscribers,
+                             _Unsubscribers = Unsubscribers}
+                    end;
+                false ->
+                    {Contacts, Subscribers}
+                        = subscriptions5(NodeIdx, Owner, Groups,
+                              _Contacts = Pubsub_Groups#pubsub_groups.contacts),
+                    %
+                    mnesia:write(Table_Pubsub_Groups,
+                        Pubsub_Groups#pubsub_groups{
+                            nodes    = [{NodeIdx, Groups}
+                                | Pubsub_Groups#pubsub_groups.nodes],
+                            contacts = Contacts
+                        },
+                        write),
+                    %
+                    {_Subscribers   = Subscribers,
+                     _Unsubscribers = []}
+            end
+    end.
+
+
+%% TODO : fix this hook managment
+-spec(monitor_contacts/3 ::
+(
+  _            :: 'subscribed',
+  Entity       :: xmpp_jid:usr_bare(),
+  Jid_Contacts :: xmpp_jid:entity_bare())
+    -> undefined
+    %
+    | {Server  :: xmpp_jid:raw_jid_component_bare(),
+       Entity  :: xmpp_jid:usr_bare(),
+       Contact :: xmpp_jid:usr_bare(),
+       _       :: {'subscribed', NodeIdxs :: nodeIdxs()}}
+).
+
+monitor_contacts('subscribed', {_, Server, _} = Entity, Jid_Contact) ->
+    case roster_groups(Entity, Contact = jlid:jid_to_lower(Jid_Contact)) of
+        [] ->
+            undefined;
+        Roster_Groups ->
+            case
+                mnesia:read(Table_Pubsub_Groups = table('pubsub_groups', dev),
+                    _Owner = Entity, write)
+            of
+                [] ->
+                    undefined;
+                [Pubsub_Groups] ->
+                    case
+                        filter_subscriptions(Pubsub_Groups#pubsub_groups.nodes,
+                            Roster_Groups)
+                    of
+                        [] ->
+                            undefined;
+                        Subscriptions ->
+                            mnesia:write(Table_Pubsub_Groups,
+                                Pubsub_Groups#pubsub_groups{
+                                    contacts = case
+                                        lists:keyreplace(Contact, 1,
+                                            Pubsub_Groups#pubsub_groups.contacts,
+                                            {Contact, Subscriptions})
+                                    of
+                                        _Contacts
+                                          when _Contacts ==
+                                               Pubsub_Groups#pubsub_groups.contacts ->
+                                            [{Contact, Subscriptions}
+                                            | Pubsub_Groups#pubsub_groups.contacts];
+                                        Contacts ->
+                                            Contacts
+                                    end
+                                },
+                                write),
+                            {Server, Entity, Contact,
+                             {'subscribed',
+                              _NodeIdx = lists:map(fun
+                                  ({NodeIdx, _Groups}) ->
+                                      NodeIdx
+                              end, Subscriptions)}}
+                    end
+            end
+    end.
+
+
+%%
+-spec(monitor_groups/2 ::
+(
+  Server :: xmpp_jid:raw_jid_component_bare(),
+  Roster :: #roster{groups :: [] | roster_groups()})
+    -> undefined
+    %
+    | {Server        :: xmpp_jid:raw_jid_component_bare(),
+       Entity        :: xmpp_jid:usr_bare(),
+       Diff_NodeIdxs :: {NodeIdxs_Subscriptions   :: [] | nodeIdxs(),
+                         NodeIdxs_Unsubscriptions :: [] | nodeIdxs()}}
+).
+
+monitor_groups(Server, #roster{us = {U,S}} = _Roster) ->
+    case
+        mnesia:read(Table_Pubsub_Groups = table('pubsub_groups', dev),
+            _Owner = {U,S,undefined}, write)
+    of
+        [] ->
+            undefined;
+        [Pubsub_Groups] ->
+            case
+                lists:keyfind(_Roster#roster.jid, 1,
+                    Pubsub_Groups#pubsub_groups.contacts)
+            of  %%
+                {_Entity, Old_Subscriptions}
+                  when   _Roster#roster.subscription == 'delete'
+                  orelse _Roster#roster.subscription == 'none' ->
+                    mnesia:write(Table_Pubsub_Groups,
+                        Pubsub_Groups#pubsub_groups{
+                            contacts = lists:keydelete(_Roster#roster.jid, 1,
+                                Pubsub_Groups#pubsub_groups.contacts)
+                        },
+                        write),
+                    {Server,
+                     _Entity = _Roster#roster.jid,
+                     _Diff_NodeIdxs = diff_nodeidxs(_New_Subscriptions = [],
+                         Old_Subscriptions)};
+               %%
+                {_Entity, Old_Subscriptions}
+                  when (_Roster#roster.subscription == 'both'
+                            orelse
+                               _Roster#roster.subscription == 'from')
+                  andalso _Roster#roster.groups == [] ->
+                    mnesia:write(Table_Pubsub_Groups,
+                        Pubsub_Groups#pubsub_groups{
+                            contacts = lists:keydelete(_Roster#roster.jid, 1,
+                                Pubsub_Groups#pubsub_groups.contacts)
+                        },
+                        write),
+                    {Server,
+                     _Roster#roster.jid,
+                     _Diff_NodeIdxs = diff_nodeidxs(_New_Subscriptions = [],
+                         Old_Subscriptions)};
+                %%
+                {_Entity, Old_Subscriptions}
+                  when   _Roster#roster.subscription == 'both'
+                  orelse _Roster#roster.subscription == 'from' ->
+                    case
+                        filter_subscriptions(Pubsub_Groups#pubsub_groups.nodes,
+                            _Roster#roster.groups)
+                    of
+                        [] ->
+                            mnesia:write(Table_Pubsub_Groups,
+                                Pubsub_Groups#pubsub_groups{
+                                    contacts = lists:keydelete(_Roster#roster.jid,
+                                        1, Pubsub_Groups#pubsub_groups.contacts)
+                                },
+                                write),
+                            {Server, _Roster#roster.jid,
+                             diff_nodeidxs(_New_Subscriptions = [],
+                                 Old_Subscriptions)};
+                        New_Subscriptions ->
+                            mnesia:write(Table_Pubsub_Groups,
+                                Pubsub_Groups#pubsub_groups{
+                                    contacts = lists:keyreplace(_Roster#roster.jid,
+                                        1, Pubsub_Groups#pubsub_groups.contacts,
+                                        {_Roster#roster.jid, New_Subscriptions})
+                                },
+                                write),
+                            {Server,
+                             _Entity = _Roster#roster.jid,
+                             _Diff_NodeIdxs = diff_nodeidxs(New_Subscriptions,
+                                 Old_Subscriptions)}
+                    end;
+                %%
+                false
+                  when (_Roster#roster.subscription == 'both'
+                            orelse
+                                _Roster#roster.subscription == 'from')
+                  andalso _Roster#roster.groups =/= [] ->
+                    case
+                        filter_subscriptions(Pubsub_Groups#pubsub_groups.nodes,
+                            _Roster#roster.groups)
+                    of
+                        [] ->
+                            undefined;
+                        New_Subscriptions ->
+                            mnesia:write(Table_Pubsub_Groups,
+                                Pubsub_Groups#pubsub_groups{
+                                    contacts = [{_Roster#roster.jid, New_Subscriptions}
+                                        | Pubsub_Groups#pubsub_groups.contacts]
+                                },
+                                write),
+                            {Server,
+                             _Entity = _Roster#roster.jid,
+                             _Diff_NodeIdxs = diff_nodeidxs(New_Subscriptions,
+                                 _Old_Subscriptions = [])}
+                    end;
+                %%
+                _ ->
+                    undefined
+            end
+    end.
+
+
+
+%%
+%%
+-spec(subscriptions1/2 ::
+(
+  NodeIdx      :: exmpp_pubsub:nodeIdx(),
+  Old_Contacts :: [] | contacts())
+    -> Diff_Contacts :: {New_Contacts  :: [] | contacts(),
+                         Unsubscribers :: [Entity::xmpp_jid:usr_bare()]}
+).
+
+subscriptions1(NodeIdx, Contacts) ->
+    _Diff_Contacts = subscriptions1(NodeIdx, _Old_Contacts = Contacts,
+        {_New_Contacts = [], _Unsubscribers = []}).
+
+
+%%
+-spec(subscriptions1/3 ::
+(
+  NodeIdx       :: exmpp_pubsub:nodeIdx(),
+  Old_Contacts  :: [] | contacts(),
+  Diff_Contacts :: {Contacts      :: [] | contacts(),
+                    Unsubscribers :: [Entity::xmpp_jid:usr_bare()]})
+    -> Diff_Contacts :: {New_Contacts  :: [] | contacts(),
+                         Unsubscribers :: [Entity::xmpp_jid:usr_bare()]}
+).
+
+subscriptions1(_NodeIdx, [] = _Old_Contacts, Diff_Contacts) ->
+    Diff_Contacts;
+%%
+subscriptions1(NodeIdx, [{Entity, Subscriptions} | Old_Contacts],
+  {Contacts, Unsubscribers}) ->
+    subscriptions1(NodeIdx, Old_Contacts,
+        _Diff_Contacts = case lists:keydelete(NodeIdx, 1, Subscriptions) of
+            [] ->
+                {_Contacts      = Contacts,
+                 _Unsubscribers = [Entity | Unsubscribers]};
+            Subscriptions ->
+                {_Contacts      = [{Entity, Subscriptions} | Contacts],
+                 _Unsubscribers = Unsubscribers};
+            New_Subscriptions ->
+                {_Contacts      = [{Entity, New_Subscriptions} | Contacts],
+                 _Unsubscribers = [Entity | Unsubscribers]}
+        end).
+
+
+%%
+-spec(subscriptions2/3 ::
+(
+  NodeIdx     :: exmpp_pubsub:nodeIdx(),
+  Owner       :: xmpp_jid:usr_bare(),
+  Node_Groups :: node_groups())
+    -> Diff_Contacts :: {Contacts    :: [] | contacts(),
+                         Subscribers :: [Entity::xmpp_jid:usr_bare()]}
+).
+
+subscriptions2(NodeIdx, Owner, Node_Groups) ->
+    subscriptions2(NodeIdx, _Rosters = get_entity_roster(Owner), Node_Groups,
+        {_New_Contacts = [], _Subscribers = []}).
+
+%%
+-spec(subscriptions2/4 ::
+(
+  NodeIdx       :: exmpp_pubsub:nodeIdx(),
+  Rosters       :: [Roster::#roster{groups :: [] | roster_groups()}],
+  Node_Groups   :: node_groups(),
+  Diff_Contacts :: {Contacts    :: [] | contacts(),
+                    Subscribers :: [Entity::xmpp_jid:usr_bare()]})
+    -> Diff_Contacts :: {Contacts    :: [] | contacts(),
+                         Subscribers :: [Entity::xmpp_jid:usr_bare()]}
+).
+
+subscriptions2(_NodeIdx, [] = _Rosters, _Node_Groups, Diff_Contacts) ->
+    Diff_Contacts;
+%%
+subscriptions2(NodeIdx, [_Roster | Rosters], Node_Groups, {Contacts, Subscribers})
+  when _Roster#roster.groups =/= [] ->
+    subscriptions2(NodeIdx, Rosters, Node_Groups,
+        _Diff_Contacts = case
+            filter_groups(_Roster#roster.groups, Node_Groups, [])
+        of
+            [] ->
+                {_Contacts    = Contacts,
+                 _Subscribers = Subscribers};
+            Roster_Groups ->
+                {_Contacts    = [{_Roster#roster.jid, [{NodeIdx, Roster_Groups}]}
+                                | Contacts],
+                 _Subscribers = [_Roster#roster.jid | Subscribers]}
+        end);
+%%
+subscriptions2(NodeIdx, [_Roster | Rosters], Node_Groups, Diff_Contacts) ->
+    subscriptions2(NodeIdx, Rosters, Node_Groups, Diff_Contacts).
+
+
+%%
+-spec(subscriptions3/3 ::
+(
+  NodeIdx       :: exmpp_pubsub:nodeIdx(),
+  Old_Groups    :: roster_groups(),
+  Contacts      :: contacts() | [])
+    -> Diff_Contacts :: {Contacts      :: [] | contacts(),
+                         Unsubscribers :: [Entity::xmpp_jid:usr_bare()]}
+).
+subscriptions3(NodeIdx, Old_Groups, Contacts) ->
+    subscriptions3(NodeIdx, Contacts, Old_Groups, {[],[]}).
+
+%%
+-spec(subscriptions3/4 ::
+(
+  NodeIdx       :: exmpp_pubsub:nodeIdx(),
+  Old_Contacts  :: contacts() | [],
+  Old_Groups    :: roster_groups(),
+  Diff_Contacts :: {Contacts      :: [] | contacts(),
+                    Unsubscribers :: [Entity::xmpp_jid:usr_bare()]})
+    -> Diff_Contacts :: {Contacts      :: [] | contacts(),
+                         Unsubscribers :: [Entity::xmpp_jid:usr_bare()]}
+).
+
+subscriptions3(_NodeIdx, [] = _Contacts, _Old_Groups, Diff_Contacts) ->
+    Diff_Contacts;
+%%
+subscriptions3(NodeIdx, [{Entity, Subscriptions} | Old_Contacts], Old_Groups,
+  {Contacts, Unsubscribers}) ->
+    subscriptions3(NodeIdx, Old_Contacts, Old_Groups,
+        _Diff_Contacts = case lists:keyfind(NodeIdx, 1, Subscriptions) of
+            {_NodeIdx, Roster_Groups} ->
+                case delete_groups(Old_Groups, Roster_Groups) of
+                    [] ->
+                        {_Contacts      = Contacts,
+                         _Unsubscribers = [Entity | Unsubscribers]};
+                    Groups ->
+                        {_Contacts      = [{Entity,
+                                            lists:keyreplace(NodeIdx, 1,
+                                                Subscriptions, {NodeIdx, Groups})}
+                                          | Contacts],
+                         _Unsubscribers = Unsubscribers}
+                end;
+            false ->
+                {_Contacts      = [{Entity, Subscriptions} | Contacts],
+                 _Unsubscribers = Unsubscribers}
+        end).
+
+
+%%
+-spec(subscriptions4/4 ::
+(
+  NodeIdx     :: exmpp_pubsub:nodeIdx(),
+  _           :: xmpp_jid:usr_bare()
+               | [Roster::#roster{groups :: [] | roster_groups()}],
+  Node_Groups :: node_groups(),
+  _           :: [] | contacts()
+               | {Contacts      :: [] | contacts(),
+                  Subscribers   :: [Entity::xmpp_jid:usr_bare()],
+                  Unsubscribers :: [Entity::xmpp_jid:usr_bare()]})
+    -> Diff_Contacts :: {Contacts      :: [] | contacts(),
+                         Subscribers   :: [Entity::xmpp_jid:usr_bare()],
+                         Unsubscribers :: [Entity::xmpp_jid:usr_bare()]}
+).
+
+subscriptions4(_NodeIdx, [] = _Rosters, _Node_Groups, Diff_Contacts) ->
+    Diff_Contacts;
+%%
+subscriptions4(NodeIdx, [_Roster | Rosters], Node_Groups,
+  {Contacts, Subscribers, Unsubscribers})
+  when _Roster#roster.groups =/= [] ->
+    subscriptions4(NodeIdx, Rosters, Node_Groups,
+        _Diff_Contacts = case
+            {lists:keyfind(Entity = _Roster#roster.jid, 1, Contacts),
+             filter_groups(_Roster#roster.groups, Node_Groups, [])}
+        of
+            %%
+            {false, [] = _Groups} ->
+                {_Contacts      = Contacts,
+                 _Subscribers   = Subscribers,
+                 _Unsubscribers = Unsubscribers};
+            %%
+            {false, Groups} ->
+                {_Contacts      = [{Entity, [{NodeIdx, Groups}]} | Contacts],
+                 _Subscribers   = [Entity | Subscribers],
+                 _Unsubscribers = Unsubscribers};
+            %%
+            {{_Entity, [{NodeIdx, _Roster_Groups}] = _Subscriptions}, [] = _Groups} ->
+                {_Contacts      = lists:keydelete(Entity, 1, Contacts),
+                 _Subscribers   = Subscribers,
+                 _Unsubscribers = [Entity | Unsubscribers]};
+            %%
+            {{_Entity, Subscriptions}, [] = _Groups} ->
+                case lists:keydelete(NodeIdx, 1, Subscriptions) of
+                    Subscriptions ->
+                        {_Contacts      = Contacts,
+                         _Subscribers   = Subscribers,
+                         _Unsubscribers = Unsubscribers};
+                    New_Subscriptions ->
+                        {_Contacts      = lists:keyreplace(Entity, 1, Contacts,
+                                              {Entity, New_Subscriptions}),
+                         _Subscribers   = Subscribers,
+                         _Unsubscribers = [Entity | Unsubscribers]}
+                end;
+            {{_Entity, Subscriptions}, Groups} ->
+                case lists:keyreplace(NodeIdx, 1, Subscriptions, {NodeIdx, Groups}) of
+                    Subscriptions ->
+                        {_Contacts      = lists:keyreplace(Entity, 1, Contacts,
+                                              {Entity,
+                                               [{NodeIdx, Groups} | Subscriptions]}),
+                         _Subscribers   = [Entity | Subscribers],
+                         _Unsubscribers = Unsubscribers};
+                    New_Subscriptions ->
+                        {_Contacts      = lists:keyreplace(Entity, 1, Contacts,
+                                              {Entity, New_Subscriptions}),
+                         _Subscribers   = Subscribers,
+                         _Unsubscribers = Unsubscribers}
+                end
+        end);
+%%
+subscriptions4(NodeIdx, [_Roster | Rosters], Node_Groups, Diff_Contacts) ->
+    subscriptions4(NodeIdx, Rosters, Node_Groups, Diff_Contacts);
+%%
+subscriptions4(NodeIdx, Owner, Node_Groups, Contacts) ->
+    subscriptions4(NodeIdx, _Rosters = get_entity_roster(Owner), Node_Groups,
+        _Diff_Contacts = {Contacts, _Subscribers = [], _Unsubscribers = []}).
+
+
+
+-spec(subscriptions5/4 ::
+(
+  NodeIdx     :: exmpp_pubsub:nodeIdx(),
+  _           :: xmpp_jid:usr_bare()
+               | [Roster::#roster{groups :: [] | roster_groups()}],
+  Node_Groups :: node_groups(),
+  _           :: [] | contacts()
+               | {Contacts    :: [] | contacts(),
+                  Subscribers :: [Entity::xmpp_jid:usr_bare()]})
+    -> Diff_Contacts :: {Contacts    :: [] | contacts(),
+                         Subscribers :: [Entity::xmpp_jid:usr_bare()]}
+).
+
+subscriptions5(NodeIdx, [_Roster | Rosters], Node_Groups, {Contacts, Subscribers})
+  when _Roster#roster.groups =/= [] ->
+    subscriptions5(NodeIdx, Rosters, Node_Groups,
+        _Diff_Contacts = case
+            filter_groups(_Roster#roster.groups, Node_Groups, [])
+        of
+            [] ->
+                {_Contacts    = Contacts,
+                 _Subscribers = Subscribers};
+            Groups ->
+                {_Contacts    = case
+                     lists:keyfind(_Roster#roster.jid, 1, Contacts)
+                 of
+                     false ->
+                         [{_Roster#roster.jid, [{NodeIdx, Groups}]} | Contacts];
+                     {Entity, Subscriptions} ->
+                         lists:keyreplace(Entity, 1, Contacts,
+                             {Entity, [{NodeIdx, Groups} | Subscriptions]})
+                 end,
+                 _Subscribers = [_Roster#roster.jid | Subscribers]}
+        end);
+%%
+subscriptions5(NodeIdx, [_Roster | Rosters], Node_Groups, Diff_Contacts) ->
+    subscriptions5(NodeIdx, Rosters, Node_Groups, Diff_Contacts);
+%%
+subscriptions5(NodeIdx, Owner, Node_Groups, Contacts) ->
+    subscriptions5(NodeIdx, _Rosters = get_entity_roster(Owner), Node_Groups,
+        _Diff_Contacts = {Contacts, _Subscribers = []}).
+
+
+%%
+-spec(delete_groups/2 ::
+(
+  Old_Groups :: roster_groups(),
+  Groups     :: [] | roster_groups())
+    -> Groups :: [] | roster_groups()
+).
+
+delete_groups(_Old_Groups, [] = _Groups) ->
+    _Groups = [];
+%%
+delete_groups([] = _Old_Groups, Groups) ->
+    Groups;
+%%
+delete_groups([Old_Group | Old_Groups], Groups) ->
+    _Groups = delete_groups(Old_Groups, lists:delete(Old_Group, Groups)).
+
+
+%%
+-spec(diff_groups/2 ::
+(
+  Groups :: node_groups() | [],
+  _      :: node_groups()
+          | {New_Groups :: []  | node_groups(),
+             Old_Groups :: []  | node_groups()})
+    -> Diff_Groups :: {New_Groups :: []  | node_groups(),
+                       Old_Groups :: []  | node_groups()}
+).
+
+diff_groups([] = _Groups, Diff_Groups) -> %% when is_tuple(Diff_Groups)
+    Diff_Groups;
+%%
+diff_groups([Group | Groups], {New_Groups, Old_Groups}) ->
+    diff_groups(Groups,
+        _Diff_Groups = case lists:delete(Group, Old_Groups) of
+            Old_Groups  -> {[Group | New_Groups], Old_Groups};
+            Old_Groups2 -> {New_Groups, Old_Groups2}
+        end);
+%%
+diff_groups(New_Groups, Old_Groups) ->
+    diff_groups(New_Groups, {[], Old_Groups}).
+
+
+%%
+-spec(filter_groups/3 ::
+(
+  Roster_Groups :: roster_groups() | [],
+  Node_Groups   :: node_groups(),
+  Groups        :: [] | roster_groups())
+    -> Groups :: [] | roster_groups()
+).
+
+filter_groups([] = _Roster_Groups, _Node_Groups, Groups) ->
+    Groups;
+%%
+filter_groups([Roster_Group | Roster_Groups], Node_Groups, Groups) ->
+    filter_groups(Roster_Groups, Node_Groups,
+        _Groups = case lists:member(Roster_Group, Node_Groups) of
+            true  -> [Roster_Group | Groups];
+            false -> Groups
+        end). 
+
+
+%%
+-spec(filter_subscriptions/2 ::
+(
+  Nodes         :: n0des(),
+  Roster_Groups :: roster_groups())
+    -> Subscriptions :: [] | subscriptions()
+).
+
+filter_subscriptions(Nodes, Roster_Groups) ->
+    _Subscriptions = filter_subscriptions(Nodes, Roster_Groups, []).
+
+%%
+-spec(filter_subscriptions/3 ::
+(
+  Nodes         :: n0des(),
+  Roster_Groups :: roster_groups(),
+  Subscriptions :: [] | subscriptions())
+    -> Subscriptions :: [] | subscriptions()
+).
+
+filter_subscriptions([] = _Nodes, _Roster_Groups, Subscriptions) ->
+    Subscriptions;
+%%
+filter_subscriptions([{NodeIdx, Node_Groups} | Nodes], Roster_Groups,
+  Subscriptions) ->
+    filter_subscriptions(Nodes, Roster_Groups,
+        _Subscriptions = case filter_groups(Roster_Groups, Node_Groups, []) of
+            []     -> Subscriptions;
+            Groups -> [{NodeIdx, Groups} | Subscriptions]
+        end).
+
+
+%%
+-spec(diff_nodeidxs/2 ::
+(
+  New_Subscriptions :: [] | subscriptions(),
+  Old_Subscriptions :: [] | subscriptions())
+    -> Diff_NodeIdxs :: {NodeIdxs_Subscriptions   :: [] | nodeIdxs(),
+                         NodeIdxs_Unsubscriptions :: [] | nodeIdxs()}
+).
+
+diff_nodeidxs(New_Subscriptions, Old_Subscriptions) ->
+    _Diff_NodeIdxs = diff_nodeidxs(New_Subscriptions, Old_Subscriptions, []).
+
+%%
+-spec(diff_nodeidxs/3 ::
+(
+  New_Subscriptions      :: [] | subscriptions(),
+  Old_Subscriptions      :: [] | subscriptions(),
+  NodeIdxs_Subscriptions :: [] | nodeIdxs())
+    -> Diff_NodeIdxs :: {NodeIdxs_Subscriptions   :: [] | nodeIdxs(),
+                         NodeIdxs_Unsubscriptions :: [] | nodeIdxs()}
+).
+
+diff_nodeidxs([] = _New_Subscriptions, Old_Subscriptions,
+  NodeIdxs_Subscriptions) ->
+    _Diff_NodeIdxs = {
+        _NodeIdxs_Subscriptions   = NodeIdxs_Subscriptions,
+        _NodeIdxs_Unsubscriptions = lists:map(fun
+            ({NodeIdx, _Roster_Groups}) ->
+               NodeIdx
+         end, Old_Subscriptions)};
+%%
+diff_nodeidxs([{NodeIdx, _Groups} | New_Subscriptions], [] = Old_Subscriptions,
+  NodeIdxs_Subscriptions) ->
+    diff_nodeidxs(New_Subscriptions, Old_Subscriptions,
+        [NodeIdx | NodeIdxs_Subscriptions]);
+%%
+diff_nodeidxs([{NodeIdx, _Groups} | New_Subscriptions], Old_Subscriptions,
+  NodeIdxs_Subscriptions) ->
+    case lists:keydelete(NodeIdx, 1, Old_Subscriptions) of
+        Old_Subscriptions ->
+            diff_nodeidxs(New_Subscriptions, Old_Subscriptions,
+                [NodeIdx | NodeIdxs_Subscriptions]);
+        Subscriptions ->
+            diff_nodeidxs(New_Subscriptions, _Old_Subscriptions = Subscriptions,
+                NodeIdxs_Subscriptions)
+    end.
+
+
+%% TODO : use a new mod_roster_api for this call
+-spec(roster_groups/2 ::
+(
+  Entity  :: xmpp_jid:usr_bare(),
+  Contact :: xmpp_jid:usr_bare())
+    -> Roster_Groups :: [] | roster_groups()
+).
+
+roster_groups({User, Server, _} = _Entity, Contact) ->   
+    _Roster_Groups = case
+        gen_storage:transaction(Server, rosteritem,
+            fun() ->
+                gen_storage:select(Server, rostergroup,
+                    [{'=', user_host_jid, {User, Server, Contact}}])
+            end)
+    of
+        {atomic, _RosterGroups} ->
+            lists:map(fun
+                (_RosterGroup) ->
+                    _RosterGroup#roster.groups
+            end, _RosterGroups);
+        _Error
+            -> {error, 'internal-server-error'}
+    end.
+
+
+%%
+-spec(select_roster_groups/1 ::
+(
+  Entity :: xmpp_jid:usr_entity())
+    -> Roster_Groups :: [] | roster_groups()
+).
+
+select_roster_groups({User, Server, _} = Entity) ->
+    _Roster_Groups = case
+        gen_storage:transaction(Server, rosteritem,
+            fun() ->
+                gen_storage:select(Server, rostergroup,
+                    [{'=', user_host_jid, {User, Server, '_'}}])
+            end)
+    of
+        {atomic, _RosterGroups} ->
+            lists:map(fun
+                (_RosterGroup) ->
+                    _RosterGroup#roster.groups
+            end, _RosterGroups);
+        _Error
+            -> {error, 'internal-server-error'}
+    end.
+
+
+%% TESTS
+
+%%
+monitor_roster_groups(Server, Roster) ->
+    ?INFO_MSG("SERVER ~p ROSTER ~p", [Server, Roster]),
+    Result = pubsub_db:transaction('mnesia', ?MODULE, monitor_groups,
+        [Server, Roster]),
+    ?INFO_MSG("MONITOR ROSTER GROUPS ~p", [Result]).
+
+
+monitor_contacts2('subscribed', Entity, Jid_Contact) ->
+    Result = pubsub_db:transaction('mnesia', ?MODULE, monitor_contacts,
+        ['subscribed', Entity, Jid_Contact]),
+    ?INFO_MSG("MONITOR CONTACTS2 ~p", [Result]).
+
+register1(NodeIdx, User, Groups) ->
+    Server = <<"localhost">>,
+    Owner = {list_to_binary(atom_to_list(User)), Server, undefined},
+    Groups_B = lists:map(fun(Group) -> list_to_binary(atom_to_list(Group)) end, Groups),
+    register_groups(dev, NodeIdx, Owner, Groups_B).
+
+register(NodeIdx, User, Groups) ->
+    pubsub_db:transaction('mnesia', ?MODULE, register1, [NodeIdx, User, Groups]).
diff --git a/src/mod_pubsub_ng/pubsub_hooks.erl b/src/mod_pubsub_ng/pubsub_hooks.erl
new file mode 100644
index 000000000..c5c1fc28a
--- /dev/null
+++ b/src/mod_pubsub_ng/pubsub_hooks.erl
@@ -0,0 +1,570 @@
+%%% ====================================================================
+%%% ``The contents of this file are subject to the Erlang Public License,
+%%% Version 1.1, (the "License"); you may not use this file except in
+%%% compliance with the License. You should have received a copy of the
+%%% Erlang Public License along with this software. If not, it can be
+%%% retrieved via the world wide web at http://www.erlang.org/.
+%%% 
+%%% Software distributed under the License is distributed on an "AS IS"
+%%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%%% the License for the specific language governing rights and limitations
+%%% under the License.
+%%% 
+%%% The Initial Developer of the Original Code is ProcessOne.
+%%% Portions created by ProcessOne are Copyright 2006-2011, ProcessOne
+%%% All Rights Reserved.''
+%%% This software is copyright 2006-2011, ProcessOne.
+%%%
+%%% @copyright 2006-2011 ProcessOne
+%%% @author Karim Gemayel <karim.gemayel@process-one.net>
+%%%   [http://www.process-one.net/]
+%%% @version {@vsn}, {@date} {@time}
+%%% @end
+%%% ====================================================================
+
+%%% @headerfile "pubsub_dev.hrl"
+
+-module(pubsub_hooks).
+-author('karim.gemayel@process-one.net').
+
+-compile(export_all).
+
+-include("pubsub_dev.hrl").
+
+-import(pubsub_tools,
+[
+  get_option/2,
+  get_option/3,
+  get_value/2,
+  get_value/3,
+  set_value/3,
+  %%
+  check_access_model/3,
+  check_access_model/7,
+  check_publish_model/3,
+  is_contact_subscribed_to_node_owners/3,
+  is_contact_in_allowed_roster_groups/2,
+  has_subscriptions/1
+]).
+
+-import(pubsub_db_mnesia,
+[
+  table/2
+]).
+
+%% 'node_config#send_last_published_item'
+-spec(presence_online/3 ::
+(
+  From   :: xmpp_jid:entity_full(),
+  To     :: xmpp_jid:entity_full(),
+  C2SPid :: pid())
+    -> 'ok'
+).
+
+presence_online(#jid{luser = U, lserver = S, lresource = R} = Jid, Jid, C2SPid) ->
+    ?INFO_MSG("PRESENCE ONLINE From ~p ~n, To ~p ~n, C2SPid ~p ~n",
+        [Jid, Jid, C2SPid]),
+    Pubsub_Features = node_flat_dev:pubsub_features(),
+    case lists:member(<<"last-published">>, Pubsub_Features) of
+        true ->
+            spawn(?MODULE, last_published_items,
+                [_Host = <<"localhost">>, {U,S,R}]);
+        false ->
+            ok
+    end;
+%%
+presence_online(_, _, _) ->
+    ok.
+
+
+%%
+-spec(last_published_items/2 ::
+(
+  Host   :: xmpp_jid:raw_jid_component_bare(),
+  Entity :: xmpp_jid:usr_full())
+    -> 'ok'
+).
+
+last_published_items(Host, {U,S,_R} = Entity) ->
+    Table_Pubsub_State = table('pubsub_state', 'dev'),
+    Table_Pubsub_Node = table('pubsub_node', 'dev'),
+    Table_Pubsub_Last_Item = table('pubsub_last_item', 'dev'),
+    lists:foreach(fun
+        (State) ->
+            last_published_items(Host, Entity, Table_Pubsub_Node,
+                Table_Pubsub_Last_Item, State)
+    end,
+        mnesia:dirty_select(Table_Pubsub_State,
+            [{#pubsub_state_dev{
+                  id            = {{U,S,undefined}, '$1'},
+                  affiliation   = '$2',
+                  access        = '$3',
+                  subscriptions = '$4',
+                  _             = '_'
+             },
+             [{'=/=', '$2', 'outcast'},
+              {'=/=', '$3', 'pending'},
+              {'=/=', '$4', []}],
+             ['$$']}])).
+
+%%
+-spec(last_published_items/5 ::
+(
+  Host              :: xmpp_jid:raw_jid_component_bare(),
+  Entity            :: xmpp_jid:usr_full(),
+  Table_Pubsub_Node :: atom(),
+  Table_Pubsub_Last_Item :: atom(),
+  State                  :: [exmpp_pubsub:nodeIdx()           |
+                             'member' | 'owner' | 'publisher' |
+                             _                                |
+                             exmpp_pubsub:subscriptions(),... ])
+    -> 'ok'
+).
+
+last_published_items(Host, {_, _, Online_Resource} = Entity,
+  Table_Pubsub_Node, Table_Pubsub_Last_Item,
+  [NodeIdx, Affiliation, _Access, Subscriptions]) ->
+    case mnesia:dirty_index_read(Table_Pubsub_Node, NodeIdx, idx) of
+        [#pubsub_node_dev{
+             id      = {Pubsub_Host, NodeId},
+             owners  = Node_Owners,
+             options = Node_Options
+         }] ->
+            case get_value(Node_Options, 'send_last_published_item') of
+                'on_sub_and_presence' ->
+                    case mnesia:dirty_read(Table_Pubsub_Last_Item, NodeIdx) of
+                        [#pubsub_last_item_dev{
+                             id       = ItemId,
+                             creation = {DateTime, Publisher},
+                             payload  = Payload,
+                             options  = Item_Options
+                         }] ->
+                            spawn(pubsub_broadcast, broadcast_publish_last2,
+                                [Host, Pubsub_Host, NodeId, Node_Options,
+                                 Node_Owners,
+                                 [{ItemId, Item_Options, Payload, Publisher, DateTime}],
+                                   Entity, Affiliation,
+                                 lists:foldl(fun
+                                    ({Subscription_State, SubId, Resource, Subscription_Options},
+                                     Acc)
+                                      when    Subscription_State =/= 'pending'
+                                      andalso (Resource == undefined
+                                                 orelse
+                                               Resource == Online_Resource) ->
+                                        [{Subscription_State, SubId,
+                                          Online_Resource, Subscription_Options}
+                                        | Acc];
+                                    (_Subscription, Acc) ->
+                                        Acc
+                                    end, [], Subscriptions)]);
+                        _ ->
+                            ok
+                    end;
+                _ ->
+                    ok
+            end;
+        _ ->
+            ok
+    end.
+
+%% 'node_config#purge_offline'
+%% 'node_config#tempsub'
+%% 'subscribe_options#expire'
+
+-spec(presence_offline/3 ::
+(
+  _   :: _,
+  Jid :: xmpp_jid:entity_full(),
+  _   :: _)
+    -> 'ok'
+).
+
+presence_offline({_DateTime, _Pid},
+  #jid{luser = U, lserver = S, lresource = Offline_Resource} = _Jid, _) ->
+    Host = <<"localhost">>,
+    Pubsub_Features = node_flat_dev:pubsub_features(),
+    Subscribe = lists:member(<<"subscribe">>, Pubsub_Features),
+    Leased_Subscription = lists:member(<<"leased-subscription">>, Pubsub_Features),
+    Purge_Nodes = lists:member(<<"purge-nodes">>, Pubsub_Features),
+    Persistent_Items = lists:member(<<"persistent-items">>, Pubsub_Features),
+    Subscription_Notifications = lists:member(<<"subscription-notifications">>,
+        Pubsub_Features),
+    Table_Pubsub_State = table('pubsub_state', 'dev'),
+    Table_Pubsub_Node = table('pubsub_node', 'dev'),
+    Online_Resources = case ejabberd_sm:get_user_resources(U, S) of
+        [] -> false;
+        _  -> true
+    end,
+    lists:foreach(fun
+        (Pubsub_State) ->
+            presence_offline(Host,
+                _Entity = {U,S,undefined},
+                Table_Pubsub_State,
+                Pubsub_State,
+                Table_Pubsub_Node,
+                Offline_Resource,
+                Online_Resources,
+                {Subscribe,
+                 Leased_Subscription,
+                 Purge_Nodes,
+                 Persistent_Items,
+                 Subscription_Notifications})
+    end,
+        mnesia:dirty_match_object(Table_Pubsub_State,
+            #pubsub_state_dev{
+                id = {{U,S,undefined}, '_'},
+                _  = '_'
+            })).
+
+%%
+-spec(presence_offline/8 ::
+(
+  Host               :: xmpp_jid:raw_jid_component_bare(),
+  Entity             :: xmpp_jid:usr_bare(),
+  Table_Pubsub_State :: atom(),
+  Pubsub_State       :: mod_pubsub_dev:pubsub_state(),
+  Table_Pubsub_Node  :: atom(),
+  Offline_Resource   :: xmpp_jid:resource_jid(),
+  Online_Resources   :: boolean(),
+  Pubsub_Features    :: {Subscribe                  :: boolean(),
+                         Leased_Subscription        :: boolean(),
+                         Purge_Nodes                :: boolean(),
+                         Persistent_Items           :: boolean(),
+                         Subscription_Notifications :: boolean()})
+    -> 'ok'
+).
+
+presence_offline(Host, Entity, Table_Pubsub_State, Pubsub_State,
+  Table_Pubsub_Node, Offline_Resource, Online_Resources,
+  {Subscribe, Leased_Subscription, Purge_Nodes, Persistent_Items,
+   Subscription_Notifications}) ->
+    case
+        mnesia:dirty_index_read(Table_Pubsub_Node,
+            Pubsub_State#pubsub_state_dev.nodeidx, idx)
+    of
+        [#pubsub_node_dev{id = {Pubsub_Host, NodeId}} = Pubsub_Node] ->
+            Node_Options = Pubsub_Node#pubsub_node_dev.options,
+
+            case
+                Subscribe == true
+                    andalso
+                get_value(Node_Options, 'tempsub') == true
+            of
+                true ->
+                    case
+                        filter_tempsub_subscriptions(
+                            get_value(Node_Options, 'notify_sub'),
+                            Pubsub_State#pubsub_state_dev.subscriptions,
+                            Offline_Resource, Online_Resources, {[], []})
+                    of
+                        %%
+                        {_Unexpired_Subscriptions, [] = _Expired_Subscriptions} ->
+                            ok;
+                        %%
+                        {[] = _Unexpired_Subscriptions, Expired_Subscriptions}
+                          when    Pubsub_State#pubsub_state_dev.affiliation == 'member'
+                          andalso Pubsub_State#pubsub_state_dev.itemids     == [] ->
+                            mnesia:dirty_delete_object(Table_Pubsub_State,
+                                Pubsub_State),
+                            Notification_Type = get_value(Node_Options,
+                                'notification_type', 'headline'),
+                            notify_subscriptions(Host, Pubsub_Host,
+                                Entity, NodeId, Notification_Type,
+                                _Recipients = case Subscription_Notifications of
+                                    true ->
+                                        case
+                                            lists:member(Entity,
+                                                Pubsub_Node#pubsub_node_dev.owners)
+                                        of
+                                            true ->
+                                                Pubsub_Node#pubsub_node_dev.owners;
+                                            false ->
+                                                [Entity
+                                                | Pubsub_Node#pubsub_node_dev.owners]
+                                        end;
+                                    false ->
+                                        Pubsub_Node#pubsub_node_dev.owners
+                                end,
+                                Expired_Subscriptions),
+                            ok;
+                        %%
+                        {Unexpired_Subscriptions, Expired_Subscriptions} ->
+                            mnesia:dirty_write(Table_Pubsub_State,
+                                Pubsub_State#pubsub_state_dev{
+                                    subscriptions = Unexpired_Subscriptions
+                                }),
+                            Notification_Type = get_value(Node_Options,
+                                'notification_type', 'headline'),
+                                notify_subscriptions(Host, Pubsub_Host,
+                                Entity, NodeId, Notification_Type,
+                                _Recipients = case Subscription_Notifications of
+                                    true ->
+                                        case
+                                            lists:member(Entity,
+                                                Pubsub_Node#pubsub_node_dev.owners)
+                                        of
+                                            true ->
+                                                Pubsub_Node#pubsub_node_dev.owners;
+                                            false ->
+                                                [Entity
+                                                | Pubsub_Node#pubsub_node_dev.owners]
+                                        end;
+                                    false ->
+                                        Pubsub_Node#pubsub_node_dev.owners
+                                end,
+                                Expired_Subscriptions),
+                            ok
+                    end;
+                _ ->
+                    case Subscribe == true andalso Leased_Subscription == true of
+                        true ->
+                            case
+                                filter_expired_subscriptions(
+                                    get_value(Node_Options, 'notify_sub'),
+                                    Pubsub_State#pubsub_state_dev.subscriptions,
+                                    Offline_Resource, Online_Resources, {[], []})
+                            of
+                        %%
+                                {_Unexpired_Subscriptions, [] = _Expired_Subscriptions} ->
+                                    ok;
+                                %%
+                                {[] = _Unexpired_Subscriptions, Expired_Subscriptions}
+                                  when Pubsub_State#pubsub_state_dev.affiliation == 'member' ->
+                                    mnesia:dirty_delete_object(Table_Pubsub_State,
+                                        Pubsub_State),
+                                    Notification_Type = get_value(Node_Options,
+                                        'notification_type', 'headline'),
+                                    notify_subscriptions(Host, Pubsub_Host,
+                                        Entity, NodeId, Notification_Type,
+                                        _Recipients = case
+                                            Subscription_Notifications
+                                        of
+                                            true ->
+                                                case
+                                                    lists:member(Entity,
+                                                    Pubsub_Node#pubsub_node_dev.owners)
+                                                of
+                                                    true ->
+                                                        Pubsub_Node#pubsub_node_dev.owners;
+                                                    false ->
+                                                        [Entity
+                                                        |Pubsub_Node#pubsub_node_dev.owners]
+                                                end;
+                                            false ->
+                                                Pubsub_Node#pubsub_node_dev.owners
+                                        end,
+                                        Expired_Subscriptions),
+                                    ok;
+                                %%
+                                {Unexpired_Subscriptions, Expired_Subscriptions} ->
+                                    mnesia:dirty_write(Table_Pubsub_State,
+                                        Pubsub_State#pubsub_state_dev{
+                                            subscriptions = Unexpired_Subscriptions
+                                        }),
+                                    Notification_Type = get_value(Node_Options,
+                                        'notification_type', 'headline'),
+                                    notify_subscriptions(Host, Pubsub_Host,
+                                        Entity, NodeId, Notification_Type,
+                                        _Recipients = case
+                                            Subscription_Notifications
+                                        of
+                                            true ->
+                                                case
+                                                    lists:member(Entity,
+                                                    Pubsub_Node#pubsub_node_dev.owners)
+                                                of
+                                                    true ->
+                                                        Pubsub_Node#pubsub_node_dev.owners;
+                                                    false ->
+                                                        [Entity
+                                                        | Pubsub_Node#pubsub_node_dev.owners]
+                                                end;
+                                            false ->
+                                                Pubsub_Node#pubsub_node_dev.owners
+                                        end,
+                                        Expired_Subscriptions),
+                                    ok
+                            end;
+                        false ->
+                            ok
+                    end
+            end;
+        [] ->
+            ok
+    end.
+
+%%
+-spec(notify_subscriptions/7 ::
+(
+  Host              :: xmpp_jid:raw_jid_component_bare(),
+  Pubsub_Host       :: exmpp_pubsub:host(),
+  Entity            :: xmpp_jid:usr_bare(),
+  NodeId            :: exmpp_pubsub:nodeId(),
+  Notification_Type :: 'message' | 'headline',
+  Recipients        :: [Entity::xmpp_jid:usr_bare(),...],
+  Subscriptions     :: [Subscription::exmpp_pubsub:subscription(),...])
+    -> 'ok'
+).
+
+notify_subscriptions(Host, Pubsub_Host, {U,S,_} = _Entity, NodeId,
+  Notification_Type, Recipients, Subscriptions) ->
+    Pubsub_Component_Jid = jlib:make_jid(<<>>, Pubsub_Host, <<>>),
+    Jids = [pubsub_tools:make_jid(Recipient) || Recipient <- Recipients],
+    lists:foreach(fun
+        ({_, SubId, Resource, _}) ->
+            Subscriber = jlib:jid_to_string({U,S,Resource}),
+            lists:foreach(fun
+                (Recipient) ->
+                    spawn(pubsub_broadcast, notify_subscription,
+                        [Host, NodeId, Pubsub_Component_Jid, Recipient,
+                         Notification_Type, {Subscriber, 'none', SubId}])
+            end, Jids)
+    end, Subscriptions).
+
+%%
+filter_purged_offline_itemids([Publisher_ItemId | Publisher_ItemIds],
+  Table_Pubsub_Item, NodeIdx, {U,S,R} = _Entity,
+  {Node_ItemIds, Unpurged_ItemIds, Purged_ItemIds}) ->
+    filter_purged_offline_itemids(Publisher_ItemIds, Table_Pubsub_Item, NodeIdx,
+        {U,S,R},
+        case
+            mnesia:dirty_index_match_object(Table_Pubsub_Item,
+                #pubsub_item_dev{
+                    id      = {Publisher_ItemId, NodeIdx},
+                    nodeidx = NodeIdx,
+                    _       = '_'
+                },
+                nodeidx)
+        of
+            [#pubsub_item_dev{creation = {_DateTime, {U,S,_}}} = Pubsub_Item] ->
+                mnesia:dirty_delete_object(Table_Pubsub_Item, Pubsub_Item);
+            _ ->
+                {Node_ItemIds,
+                 [Publisher_ItemId | Unpurged_ItemIds],
+                 Purged_ItemIds}
+        end).
+
+
+%%
+-spec(filter_tempsub_subscriptions/5 ::
+(
+  Notify_Sub                     :: boolean() | 'none',
+  Subscriptions                  :: [] | exmpp_pubsub:subscriptions(),
+  Offline_Resource               :: xmpp_jid:resource_jid(),
+  Online_Resources               :: boolean(),
+  Filtered_TempSub_Subscriptions :: {
+      Unexpired_Subscriptions :: [] | exmpp_pubsub:subscriptions(),
+      Expired_Subscriptions   :: [] | exmpp_pubsub:subscriptions()
+  })
+    -> Filtered_TempSub_Subscriptions :: {
+           Unexpired_Subscriptions :: [] | exmpp_pubsub:subscriptions(),
+           Expired_Subscriptions   :: [] | exmpp_pubsub:subscriptions()
+       }
+).
+
+filter_tempsub_subscriptions(_Notify_Sub, [] = _Subscriptions,
+  _Offline_Resource, _Online_Resources, Filtered_TempSub_Subscriptions) ->
+    Filtered_TempSub_Subscriptions;
+%%
+filter_tempsub_subscriptions(Notify_Sub,
+  [{Subscription_State, SubId, Resource, Subscription_Options} | Subscriptions],
+  Offline_Resource, Online_Resources,
+  {Unexpired_Subscriptions, Expired_Subscriptions})
+  when ((Online_Resources == false
+             andalso
+        (Resource == undefined orelse Resource == Offline_Resource))
+  orelse
+        (Online_Resources == true
+             andalso
+         Resource == Offline_Resource)) ->
+    filter_tempsub_subscriptions(Notify_Sub, Subscriptions, Offline_Resource,
+        Online_Resources,
+        {Unexpired_Subscriptions,
+         _Expired_Subscriptions = case Notify_Sub of
+             true ->
+                [{Subscription_State, SubId, Resource, Subscription_Options}
+                | Expired_Subscriptions];
+             _ ->
+                Expired_Subscriptions
+         end});
+%%
+filter_tempsub_subscriptions(Notify_Sub, [Subscription | Subscriptions],
+  Offline_Resource, Online_Resources,
+  {Unexpired_Subscriptions, Expired_Subscriptions}) ->
+    filter_tempsub_subscriptions(Notify_Sub, Subscriptions, Offline_Resource,
+        Online_Resources,
+        {[Subscription | Unexpired_Subscriptions], Expired_Subscriptions}).
+
+%%
+-spec(filter_expired_subscriptions/5 ::
+(
+  Notify_Sub                     :: boolean() | 'none',
+  Subscriptions                  :: [] | exmpp_pubsub:subscriptions(),
+  Offline_Resource               :: xmpp_jid:resource_jid(),
+  Online_Resources               :: boolean(),
+  Filtered_Expired_Subscriptions :: {
+      Unexpired_Subscriptions :: [] | exmpp_pubsub:subscriptions(),
+      Expired_Subscriptions   :: [] | exmpp_pubsub:subscriptions()
+  })
+    -> Filtered_Expired_Subscriptions :: {
+           Unexpired_Subscriptions :: [] | exmpp_pubsub:subscriptions(),
+           Expired_Subscriptions   :: [] | exmpp_pubsub:subscriptions()
+       }
+).
+
+filter_expired_subscriptions(_Notify_Sub, [] = _Subscriptions, _Offline_Resource,
+  _Online_Resources, Filtered_Expired_Subscriptions) ->
+    Filtered_Expired_Subscriptions;
+%%
+filter_expired_subscriptions(Notify_Sub,
+  [{Subscription_State, SubId, Resource, Subscription_Options} | Subscriptions],
+  Offline_Resource, Online_Resources,
+  {Unexpired_Subscriptions, Expired_Subscriptions})
+  when    Subscription_Options =/= []
+  andalso ((Online_Resources == false
+                andalso
+           (Resource == undefined orelse Resource == Offline_Resource))
+                        orelse
+           (Online_Resources == true
+                 andalso
+            Resource == Offline_Resource)) ->
+    filter_expired_subscriptions(Notify_Sub, Subscriptions, Offline_Resource,
+        Online_Resources,
+        case get_value(Subscription_Options, 'expire') of
+            'presence' ->
+                {Unexpired_Subscriptions,
+                 _Expired_Subscriptions = case Notify_Sub of
+                    true ->
+                        [{Subscription_State, SubId, Resource, Subscription_Options}
+                        | Expired_Subscriptions];
+                    false ->
+                        Expired_Subscriptions
+                 end};
+            _ ->
+                {[{Subscription_State, SubId, Resource, Subscription_Options}
+                 | Unexpired_Subscriptions],
+                 Expired_Subscriptions}
+        end);
+%%
+filter_expired_subscriptions(Notify_Sub, [Subscription | Subscriptions],
+  Offline_Resource, Online_Resources,
+  {Unexpired_Subscriptions, Expired_Subscriptions}) ->
+    filter_expired_subscriptions(Notify_Sub, Subscriptions, Offline_Resource,
+        Online_Resources,
+        {[Subscription | Unexpired_Subscriptions], Expired_Subscriptions}).
+
+
+%%
+roster_process_item(Roster_Item, Server) ->
+    spawn(pubsub_groups, monitor_roster_groups, [Server, Roster_Item]),
+    Roster_Item.
+
+
+
+roster_in_subscription(Boolean, User, Server, Jid_Contact,
+  'subscribed' = _Subscription_Type) ->
+    spawn(pubsub_groups, monitor_contacts2,
+        ['subscribed', {User, Server, undefined}, Jid_Contact]),
+    Boolean;
+roster_in_subscription(Boolean, _User, _Server, _JID, _SubscriptionType) ->
+    Boolean.
diff --git a/src/mod_pubsub_ng/pubsub_index_dev.erl b/src/mod_pubsub_ng/pubsub_index_dev.erl
new file mode 100644
index 000000000..72a8c82e6
--- /dev/null
+++ b/src/mod_pubsub_ng/pubsub_index_dev.erl
@@ -0,0 +1,113 @@
+%%% ====================================================================
+%%% ``The contents of this file are subject to the Erlang Public License,
+%%% Version 1.1, (the "License"); you may not use this file except in
+%%% compliance with the License. You should have received a copy of the
+%%% Erlang Public License along with this software. If not, it can be
+%%% retrieved via the world wide web at http://www.erlang.org/.
+%%% 
+%%% Software distributed under the License is distributed on an "AS IS"
+%%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%%% the License for the specific language governing rights and limitations
+%%% under the License.
+%%% 
+%%% The Initial Developer of the Original Code is ProcessOne.
+%%% Portions created by ProcessOne are Copyright 2006-2011, ProcessOne
+%%% All Rights Reserved.''
+%%% This software is copyright 2006-2011, ProcessOne.
+%%%
+%%%
+%%% @copyright 2006-2011 ProcessOne
+%%% @author Christophe Romain <christophe.romain@process-one.net>
+%%%   [http://www.process-one.net/]
+%%% @version {@vsn}, {@date} {@time}
+%%% @end
+%%% ====================================================================
+
+%% important note:
+%% new/1 and free/2 MUST be called inside a transaction bloc
+
+-module(pubsub_index_dev).
+-author('christophe.romain@process-one.net').
+
+-include("pubsub_dev.hrl").
+
+-export([
+  init/1,
+  new/2,
+  free/3
+]).
+
+-import(pubsub_db_mnesia,
+[
+  table/2
+]).
+
+
+%%
+-spec(init/1 ::
+(
+  Suffix::atom()) -> 'ok'
+).
+
+init(Suffix) ->
+    mnesia:create_table(table('pubsub_index_dev', Suffix),
+        [{disc_copies, [node()]},
+         {record_name, pubsub_index_dev},
+         {attributes, record_info(fields, pubsub_index_dev)}]).
+
+%%
+-spec(new/2 ::
+(
+  Suffix :: atom(),
+  Index  :: exmpp_pubsub:index())
+    -> Idx::exmpp_pubsub:nodeIdx()
+).
+
+new(Suffix, Index) ->
+    case
+        mnesia:read(Table_Pubsub_Index = table('pubsub_index_dev', Suffix),
+            Index, write)
+    of
+        [#pubsub_index_dev{free = []} = Pubsub_Index] ->
+            mnesia:write(Table_Pubsub_Index,
+                Pubsub_Index#pubsub_index_dev{
+                    last = Idx = Pubsub_Index#pubsub_index_dev.last + 1
+                },
+                write),
+            Idx;
+        [#pubsub_index_dev{free = [Idx|Free]} = Pubsub_Index] ->
+            mnesia:write(Table_Pubsub_Index,
+                Pubsub_Index#pubsub_index_dev{
+                    free = Free
+                },
+                write),
+            Idx;
+        _ ->
+            mnesia:write(Table_Pubsub_Index,
+                #pubsub_index_dev{index = Index, last = 1, free = []}, write),
+            1
+    end.
+
+%%
+-spec(free/3 ::
+(
+  Suffix :: atom(),
+  Index  :: exmpp_pubsub:index(),
+  Idx    :: exmpp_pubsub:nodeIdx())
+    -> 'ok'
+).
+
+free(Suffix, Index, Idx) ->
+    case
+        mnesia:read(Table_Pubsub_Index = table('pubsub_index_dev', Suffix),
+            Index, write)
+    of
+        [Pubsub_Index] ->
+            mnesia:write(Table_Pubsub_Index,
+                Pubsub_Index#pubsub_index_dev{
+                    free = [Idx | Pubsub_Index#pubsub_index_dev.free]
+                },
+                write);
+        _ ->
+            ok
+    end.
diff --git a/src/mod_pubsub_ng/pubsub_options.erl b/src/mod_pubsub_ng/pubsub_options.erl
new file mode 100644
index 000000000..46c9c2dd4
--- /dev/null
+++ b/src/mod_pubsub_ng/pubsub_options.erl
@@ -0,0 +1,3369 @@
+%%% ====================================================================
+%%% ``The contents of this file are subject to the Erlang Public License,
+%%% Version 1.1, (the "License"); you may not use this file except in
+%%% compliance with the License. You should have received a copy of the
+%%% Erlang Public License along with this software. If not, it can be
+%%% retrieved via the world wide web at http://www.erlang.org/.
+%%% 
+%%% Software distributed under the License is distributed on an "AS IS"
+%%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%%% the License for the specific language governing rights and limitations
+%%% under the License.
+%%% 
+%%% The Initial Developer of the Original Code is ProcessOne.
+%%% Portions created by ProcessOne are Copyright 2006-2011, ProcessOne
+%%% All Rights Reserved.''
+%%% This software is copyright 2006-2011, ProcessOne.
+%%%
+%%% @copyright 2006-2011 ProcessOne
+%%% @author Karim Gemayel <karim.gemayel@process-one.net>
+%%%   [http://www.process-one.net/]
+%%% @version {@vsn}, {@date} {@time}
+%%% @end
+%%% ====================================================================
+
+%%% @headerfile "pubsub_dev.hrl"
+
+-module(pubsub_options).
+-author('karim.gemayel@process-one.net').
+
+-compile(export_all).
+
+-include("pubsub_dev.hrl").
+
+-import(xml,
+[
+  get_tag_cdata/1,
+  get_tag_attr_s/2,
+  remove_cdata/1
+]).
+
+
+-import(pubsub_tools,
+[
+  get_entity_roster/1,
+  is_jid/1
+]).
+
+
+%% --------------------------------------------------------------------
+%% Documentation / type definitions.
+%% --------------------------------------------------------------------
+
+%% Node Options
+%  pubsub#node_config FORM_TYPE
+
+% Defined options values
+
+%-- Access Model --%
+-export_type([
+  access_model/0,
+  access_model_open/0,
+  access_model_presence/0,
+  access_model_roster/0,
+  access_model_authorize/0,
+  access_model_whitelist/0
+]).
+
+%% @type access_model_open() = 'open'.
+-type(access_model_open() :: 'open').
+
+%% @type access_model_presence() = 'presence'.
+-type(access_model_presence() :: 'presence').
+
+%% @type access_model_roster() = 'roster'.
+-type(access_model_roster() :: 'roster').
+
+%% @type access_model_authorize() = 'authorize'.
+-type(access_model_authorize() :: 'authorize').
+
+%% @type access_model_whitelist() = 'whitelist'.
+-type(access_model_whitelist() :: 'whitelist').
+
+%% @type access_model() = Open | Presence | Roster | Authorize | Whitelist
+%%    Open = pubsub_options:access_model_open()
+%%    Presence = pubsub_options:access_model_presence()
+%%    Roster = pubsub_options:access_model_roster()
+%%    Authorize = pubsub_options:access_model_authorize()
+%%    Whitelist = pubsub_options:access_model_whitelist().
+-type(access_model() :: pubsub_options:access_model_open()
+                      | pubsub_options:access_model_presence()
+                      | pubsub_options:access_model_roster()
+                      | pubsub_options:access_model_authorize()
+                      | pubsub_options:access_model_whitelist()
+).
+
+%%
+
+%-- Children_Association_Policy --%
+-export_type([
+  children_association_policy/0,
+  %%
+  children_association_policy_all/0,
+  children_association_policy_owners/0,
+  children_association_policy_whitelist/0
+]).
+
+%% @type children_association_policy_all() = 'all'.
+-type(children_association_policy_all() :: 'all').
+
+%% @type children_association_policy_owners() = 'owners'.
+-type(children_association_policy_owners() :: 'owners').
+
+%% @type children_association_policy_whitelist() = 'whitelist'.
+-type(children_association_policy_whitelist() :: 'whitelist').
+
+%% @type children_association_policy() = All | Owners | Whitelist
+%%    All = pubsub_options:children_association_policy_all()
+%%    Owners = pubsub_options:children_association_policy_owners()
+%%    Whitelist = pubsub_options:children_association_policy_whitelist().
+-type(children_association_policy()
+  :: pubsub_options:children_association_policy_all()
+   | pubsub_options:children_association_policy_owners()
+   | pubsub_options:children_association_policy_whitelist()
+).
+
+%%
+
+%-- ItemReply -- %%
+-export_type([
+  item_reply/0,
+  item_reply_owner/0,
+  item_reply_publisher/0
+]).
+
+%% @type(item_reply_owner() = 'owner').
+-type(item_reply_owner() :: 'owner').
+
+%% @type(item_reply_publisher() = 'publisher').
+-type(item_reply_publisher() :: 'publisher').
+
+%% @type(item_reply() = Owner | Publisher).
+-type(item_reply() :: pubsub_options:item_reply_owner()
+                    | pubsub_options:item_reply_publisher()
+).
+
+
+-export_type([
+  language/0,
+  description/0,
+  title/0
+]).
+
+-type(language() :: binary()).
+
+-type(description() :: binary()).
+
+-type(title() :: binary()).
+
+%%
+
+%-- Node types --%%
+
+-export_type([
+  node_type/0,
+  node_type_leaf/0,
+  node_type_collection/0
+]).
+
+%% @type node_type_collection() = 'collection'.
+-type(node_type_collection() :: 'collection').
+
+%% @type node_type_leaf() = 'leaf'.
+-type(node_type_leaf() :: 'leaf').
+
+%% @type node_type() = Leaf | Collection
+%%    Leaf = pubsub_options:node_type_leaf()
+%%    Collection = pubsub_options:node_type_collection()
+-type(node_type() :: pubsub_options:node_type_leaf()
+                   | pubsub_options:node_type_collection()
+).
+
+%%
+
+%-- Notification Types --%%
+-export_type([
+  notification_type/0,
+  notification_type_chat/0,
+  notification_type_headline/0,
+  notification_type_normal/0
+]).
+
+-type(notification_type_chat() :: 'chat').
+
+-type(notification_type_headline() :: 'headline').
+
+-type(notification_type_normal() :: 'normal').
+
+-type(notification_type()
+  :: pubsub_options:notification_type_headline()
+   | pubsub_options:notification_type_normal()
+  %| pubsub_options:notification_type_chat()
+).
+
+%%
+
+%-- Publish Model --%
+-export_type([
+  publish_model/0,
+  publish_model_publishers/0,
+  publish_model_subscribers/0,
+  publish_model_open/0
+]).
+
+%% @type publish_model_publishers() = 'publishers'.
+-type(publish_model_publishers() :: 'publishers').
+
+%% @type publish_model_subscribers() = 'subscribers'.
+-type(publish_model_subscribers() :: 'subscribers').
+
+%% @type publish_model_open() = 'open'.
+-type(publish_model_open() :: 'open').
+
+%% @type publish_model() = Publishers | Subscribers | Open
+%%    Publishers = pubsub_options:publish_model_publishers()
+%%    Subscribers = pubsub_options:publish_model_subscribers()
+%%    Open = pubsub_options:publish_model_open()
+-type(publish_model() :: pubsub_options:publish_model_publishers()
+                       | pubsub_options:publish_model_subscribers()
+                       | pubsub_options:publish_model_open()
+).
+
+
+-export_type([
+  roster_group/0,
+  roster_groups/0,
+  roster_groups_allowed/0,
+  rosters_groups_allowed/0
+]).
+
+-type(roster_group() :: binary()).
+-type(roster_groups() :: [pubsub_options:roster_group()]).
+-type(roster_groups_allowed()
+  :: {Node_Owner::xmpp_jid:usr_bare(),
+      Roster_Groups::pubsub_options:roster_groups()}
+).
+-type(rosters_groups_allowed()
+  :: [Roster_Group_Allowed::pubsub_options:roster_groups_allowed()]
+).
+
+%%
+
+%-- Send Last Published Item --%
+-export_type([
+  send_last_published_item/0,
+  %%
+  send_last_published_item_never/0,
+  send_last_published_item_on_sub/0,
+  send_last_published_item_on_sub_and_presence/0
+]).
+
+%% @type send_last_published_item_never() = 'never'.
+-type(send_last_published_item_never() :: 'never').
+
+%% @type send_last_published_item_on_sub() = 'on_sub'.
+-type(send_last_published_item_on_sub() :: 'on_sub').
+
+%% @type send_last_published_item_on_sub_and_presence() = 'on_sub_and_presence'.
+-type(send_last_published_item_on_sub_and_presence() :: 'on_sub_and_presence').
+
+%% @type send_last_published_item() = Never | On_Sub | On_Sub_And_Presence
+%%    Never = pubsub_options:send_last_published_item_never()
+%%    On_Sub = pubsub_options:send_last_published_item_on_sub()
+%%    On_Sub_And_Presence = pubsub_options:send_last_published_item_on_sub_and_presence().
+-type(send_last_published_item()
+  :: pubsub_options:send_last_published_item_never()
+   | pubsub_options:send_last_published_item_on_sub()
+   | pubsub_options:send_last_published_item_on_sub_and_presence()
+).
+
+%%
+
+
+-export_type([
+  option_node_access_model/0,
+  option_node_children_association_policy/0,
+  option_node_children_association_whitelist/0,
+  option_node_children/0,
+  option_node_children_max/0,
+  option_node_collections/0,
+  option_node_children_max_collections/0,
+  option_node_children_max_multi_collections/0,
+  option_node_contact/0,
+  option_node_deliver_notifications/0,
+  option_node_deliver_payloads/0,
+  option_node_description/0,
+  option_node_item_expire/0,
+  option_node_itemreply/0,
+  option_node_language/0,
+  option_node_max_items/0,
+  option_node_max_payload_size/0,
+  option_node_node_type_leaf/0,
+  option_node_node_type_collection/0,
+  option_node_node_type/0,
+  option_node_notification_type/0,
+  option_node_notify_config/0,
+  option_node_notify_delete/0,
+  option_node_notify_retract/0,
+  option_node_notify_sub/0,
+  option_node_persist_items/0,
+  option_node_presence_based_delivery/0,
+  option_node_publish_model/0,
+  option_node_purge_offline/0,
+  option_node_roster_groups_allowed/0,
+  option_node_send_last_published_item/0,
+  option_node_tempsub/0,
+  option_node_subscribe/0,
+  option_node_title/0,
+  option_node_type/0
+]).
+
+-type(option_node_access_model() ::
+  {Key   :: 'access_model',
+   Value :: pubsub_options:access_model()}
+).
+
+%-type(option_node_body_xslt() ::
+%  {Key   :: 'body_xslt(',
+%   Value :: binary()}
+%).
+
+-type(option_node_children_association_policy() ::
+  {Key   :: 'children_association_policy',
+   Value :: pubsub_options:children_association_policy()}
+).
+
+-type(option_node_children_association_whitelist() ::
+  {Key   :: 'children_association_whitelist',
+   Value :: [Jid_Entity::xmpp_jid:raw_jid_entity_bare()]}
+).
+
+-type(option_node_children() ::
+  {Key   :: 'children',
+   Value :: [NodeId::exmpp_pubsub:nodeId()]}
+).
+
+-type(option_node_children_max() ::
+  {Key   :: 'children_max',
+   Value :: undefined | non_neg_integer()}
+).
+
+-type(option_node_children_max_collections() ::
+  {Key   :: 'children_max',
+   Value :: undefined | 0..1}
+).
+
+-type(option_node_children_max_multi_collections() ::
+  {Key   :: 'children_max',
+   Value :: undefined | non_neg_integer()}
+).
+
+
+-type(option_node_collections() ::
+  {Key   :: 'collection',
+   Value :: [NodeId::exmpp_pubsub:nodeId()]}
+).
+
+-type(option_node_contact() ::
+  {Key   :: 'contact',
+   Value :: [Jid_Entity::xmpp_jid:raw_jid_entity()]}
+).
+
+%-type(option_node_dataform_xslt() ::
+%  {Key   :: 'dataform_xslt',
+%   Value :: binary()}
+%).
+
+-type(option_node_deliver_notifications() ::
+  {Key   :: 'deliver_notifications',
+   Value :: boolean()}
+).
+
+-type(option_node_deliver_payloads() ::
+  {Key   :: 'deliver_payloads',
+   Value :: boolean()}
+).
+
+-type(option_node_description() ::
+  {Key   :: 'description',
+   Value :: undefined | pubsub_options:description()}
+).
+
+-type(option_node_item_expire() ::
+  {Key   :: 'item_expire',
+   Value :: undefined | non_neg_integer()}
+).
+
+-type(option_node_itemreply() ::
+  {Key   :: 'itemreply',
+   Value :: pubsub_options:item_reply()}
+).
+
+-type(option_node_language() ::
+  {Key   :: 'language',
+   Value :: undefined | pubsub_options:language()}
+).
+
+-type(option_node_max_items() ::
+  {Key   :: 'max_items',
+   Value :: undefined | non_neg_integer()}
+).
+
+-type(option_node_max_payload_size() ::
+  {Key   :: 'max_payload_size',
+   Value :: undefined | non_neg_integer()}
+).
+
+-type(option_node_node_type_leaf() ::
+  {Key   :: 'node_type',
+   Value :: pubsub_options:node_type_leaf()}
+).
+
+-type(option_node_node_type_collection() ::
+  {Key   :: 'node_type',
+   Value :: pubsub_options:node_type_collection()}
+).
+
+-type(option_node_node_type()
+  :: pubsub_options:option_node_node_type_leaf()
+   | pubsub_options:option_node_node_type_collection()
+).
+
+-type(option_node_notification_type() ::
+  {Key   :: 'notification_type',
+   Value :: pubsub_options:notification_type()}
+).
+
+-type(option_node_notify_config() ::
+  {Key   :: 'notify_config',
+   Value :: boolean()}
+).
+
+-type(option_node_notify_delete() ::
+  {Key   :: 'notify_delete',
+   Value :: boolean()}
+).
+
+-type(option_node_notify_retract() ::
+  {Key   :: 'notify_retract',
+   Value :: boolean()}
+).
+
+-type(option_node_notify_sub() ::
+  {Key   :: 'notify_sub',
+   Value :: boolean()}
+).
+
+-type(option_node_persist_items() ::
+  {Key   :: 'persist_items',
+   Value :: boolean()}
+).
+
+-type(option_node_presence_based_delivery() ::
+  {Key   :: 'presence_based_delivery',
+   Value :: boolean()}
+).
+
+-type(option_node_publish_model() ::
+  {Key   :: 'publish_model',
+   Value :: pubsub_options:publish_model()}
+).
+
+-type(option_node_purge_offline() ::
+  {Key   :: 'purge_offline',
+   Value :: boolean()}
+).
+
+-type(option_node_roster_groups_allowed() ::
+  {Key   :: 'roster_groups_allowed',
+   Value :: pubsub_options:rosters_groups_allowed()}
+).
+
+-type(option_node_send_last_published_item() ::
+  {Key   :: 'send_last_published_item',
+   Value :: pubsub_options:send_last_published_item()}
+).
+
+-type(option_node_tempsub() ::
+  {Key   :: 'tempsub',
+   Value :: boolean()}
+).
+
+-type(option_node_subscribe() ::
+  {Key   :: 'subscribe',
+   Value :: boolean()}
+).
+
+-type(option_node_title() ::
+  {Key   :: 'title',
+   Value :: undefined | pubsub_options:title()}
+).
+
+-type(option_node_type() ::
+  {Key   :: 'type',
+   Value :: undefined | binary()}
+).
+
+
+
+%-- Node Option Type (local or remote user ; leaf or collection node) --%
+-export_type([
+  option_node/0,
+  options_node/0,
+  %%
+  option_node_leaf/0,
+  option_node_collection/0,
+  %%
+  options_node_leaf/0,
+  options_node_collection/0
+]).
+ 
+-type(option_node_leaf()
+  :: pubsub_options:option_node_access_model()
+   | pubsub_options:option_node_collections()
+   | pubsub_options:option_node_contact()
+   | pubsub_options:option_node_deliver_notifications()
+   | pubsub_options:option_node_deliver_payloads()
+   | pubsub_options:option_node_description()
+   | pubsub_options:option_node_item_expire()
+   | pubsub_options:option_node_itemreply()
+   | pubsub_options:option_node_language()
+   | pubsub_options:option_node_max_items()
+   | pubsub_options:option_node_max_payload_size()
+   | pubsub_options:option_node_node_type_leaf()
+   | pubsub_options:option_node_notification_type()
+   | pubsub_options:option_node_notify_config()
+   | pubsub_options:option_node_notify_delete()
+   | pubsub_options:option_node_notify_retract()
+   | pubsub_options:option_node_notify_sub()
+   | pubsub_options:option_node_persist_items()
+   | pubsub_options:option_node_presence_based_delivery()
+   | pubsub_options:option_node_publish_model()
+   | pubsub_options:option_node_purge_offline()
+   | pubsub_options:option_node_roster_groups_allowed()   
+   | pubsub_options:option_node_send_last_published_item()
+   | pubsub_options:option_node_tempsub()
+   | pubsub_options:option_node_subscribe()
+   | pubsub_options:option_node_title()
+   | pubsub_options:option_node_type()
+).
+
+%%
+-type(option_node_collection()
+  :: pubsub_options:option_node_access_model()
+   | pubsub_options:option_node_children_association_policy()
+   | pubsub_options:option_node_children_association_whitelist()
+   | pubsub_options:option_node_children()
+   | pubsub_options:option_node_children_max()
+   | pubsub_options:option_node_collections()
+   | pubsub_options:option_node_contact()
+   | pubsub_options:option_node_deliver_notifications()
+   | pubsub_options:option_node_deliver_payloads()
+   | pubsub_options:option_node_description()
+   | pubsub_options:option_node_item_expire()
+   | pubsub_options:option_node_itemreply()
+   | pubsub_options:option_node_language()
+   | pubsub_options:option_node_max_items()
+   | pubsub_options:option_node_max_payload_size()
+   | pubsub_options:option_node_node_type_collection()
+   | pubsub_options:option_node_notification_type()
+   | pubsub_options:option_node_notify_config()
+   | pubsub_options:option_node_notify_delete()
+   | pubsub_options:option_node_notify_retract()
+   | pubsub_options:option_node_notify_sub()
+   | pubsub_options:option_node_persist_items()
+   | pubsub_options:option_node_presence_based_delivery()
+   | pubsub_options:option_node_publish_model()
+   | pubsub_options:option_node_purge_offline()
+   | pubsub_options:option_node_roster_groups_allowed()
+   | pubsub_options:option_node_send_last_published_item()
+   | pubsub_options:option_node_tempsub()
+   | pubsub_options:option_node_subscribe()
+   | pubsub_options:option_node_title()
+   | pubsub_options:option_node_type()
+).
+
+%%
+-type(option_node()
+  :: pubsub_options:option_node_leaf()
+   | pubsub_options:option_node_collection()
+).
+
+%%
+-type(options_node_leaf()
+  :: [pubsub_options:option_node_leaf(),...]
+).
+
+%%
+-type(options_node_collection()
+  :: [pubsub_options:option_node_collection(),...]
+).
+
+%%
+-type(options_node()
+  :: pubsub_options:options_node_leaf()
+   | pubsub_options:options_node_collection()
+).
+
+%-- Publish-Options --%
+%% pubsub#publish-options FORM_TYPE
+-export_type([
+  option_item_access_model/0,
+  option_item_deliver_notifications/0,
+  option_item_deliver_payloads/0,
+  option_item_item_expire/0,
+  option_item_itemreply/0,
+%%option_item_max_payload_size/0,
+  option_item_notification_type/0,
+  option_item_notify_config/0,
+  option_item_notify_retract/0,
+  option_item_persist_items/0,
+  option_item_presence_based_delivery/0,
+  option_item_publish_model/0,
+  option_item_purge_offline/0,
+  option_item_roster_groups_allowed/0,
+  option_item_send_last_published_item/0,
+  option_item_type/0
+]).
+
+-type(option_item_access_model() ::
+  {Key   :: 'access_model',
+   Value :: pubsub_options:access_model()}
+).
+
+-type(option_item_deliver_notifications() ::
+  {Key   :: 'deliver_notifications',
+   Value :: boolean()}
+).
+
+-type(option_item_deliver_payloads() ::
+  {Key   :: 'deliver_payloads',
+   Value :: boolean()}
+).
+
+-type(option_item_item_expire() ::
+  {Key   :: 'item_expire',
+   Value :: undefined | non_neg_integer()}
+).
+
+-type(option_item_itemreply() ::
+  {Key   :: 'itemreply',
+   Value :: pubsub_options:item_reply()}
+).
+
+%-type(option_item_max_payload_size() ::
+%  {Key   :: 'max_payload_size',
+%   Value :: undefined | non_neg_integer()}
+%).
+
+-type(option_item_notification_type() ::
+  {Key   :: 'notification_type',
+   Value :: pubsub_options:notification_type()}
+).
+
+-type(option_item_notify_config() ::
+  {Key   :: 'notify_config',
+   Value :: boolean()}
+).
+
+-type(option_item_notify_retract() ::
+  {Key   :: 'notify_retract',
+   Value :: boolean()}
+).
+
+-type(option_item_persist_items() ::
+  {Key   :: 'persist_items',
+   Value :: boolean()}
+).
+
+-type(option_item_presence_based_delivery() ::
+  {Key   :: 'presence_based_delivery',
+   Value :: boolean()}
+).
+
+-type(option_item_publish_model() ::
+  {Key   :: 'publish_model',
+   Value :: pubsub_options:publish_model()}
+).
+
+-type(option_item_purge_offline() ::
+  {Key   :: 'purge_offline',
+   Value :: boolean()}
+).
+
+-type(option_item_roster_groups_allowed() ::
+  {Key   :: 'roster_groups_allowed',
+   Value :: pubsub_options:rosters_groups_allowed()}
+).
+
+-type(option_item_send_last_published_item() ::
+  {Key   :: 'send_last_published_item',
+   Value :: pubsub_options:send_last_published_item()}
+).
+
+-type(option_item_type() ::
+  {Key   :: 'type',
+   Value :: undefined | binary()}
+).
+
+-export_type([
+  option_item/0,
+  options_item/0
+]).
+
+-type(option_item()
+  :: pubsub_options:option_item_access_model()
+   | pubsub_options:option_item_deliver_notifications()
+   | pubsub_options:option_item_deliver_payloads()
+   | pubsub_options:option_item_item_expire()
+   | pubsub_options:option_item_itemreply()
+%% | pubsub_options:option_item_max_payload_size()
+   | pubsub_options:option_item_notification_type()
+   | pubsub_options:option_item_notify_config()
+   | pubsub_options:option_item_notify_retract()
+   | pubsub_options:option_item_persist_items()
+   | pubsub_options:option_item_presence_based_delivery()
+   | pubsub_options:option_item_publish_model()
+   | pubsub_options:option_item_purge_offline()
+   | pubsub_options:option_item_roster_groups_allowed()
+   | pubsub_options:option_item_send_last_published_item()
+   | pubsub_options:option_item_type()
+).
+
+%%
+-type(options_item()
+  :: [pubsub_options:option_item(),...]
+).
+
+
+%-- Subscription Options --%%
+-export_type([
+  option_subscription_deliver/0,
+  option_subscription_expire/0,
+  option_subscription_expire_presence/0,
+  option_subscription_expire_datetime/0,
+  option_subscription_include_body/0,
+  option_subscription_show_values/0,
+  option_subscription_subscription_type/0,
+  option_subscription_subscription_depth/0
+]).
+
+%%
+-type(option_subscription_deliver() ::
+  {Key   :: 'deliver',
+   Value :: boolean()}
+).
+
+%-type(option_subscription_digest() ::
+%  {Key   :: 'digest',
+%   Value :: boolean()}
+%).
+
+%-type(option_subscription_digest_frequency() ::
+%  {Key   :: 'digest_frequency',
+%   Value :: undefined | non_neg_integer()}
+%).
+
+-type(option_subscription_expire_presence() ::
+  {Key   :: 'expire',
+   Value :: undefined | 'presence'}
+).
+
+-type(option_subscription_expire_datetime() ::
+  {Key   :: 'expire',
+   Value :: undefined | erlang:timestamp()}
+).
+
+-type(option_subscription_expire()
+  :: pubsub_options:option_subscription_expire_presence()
+   | pubsub_options:option_subscription_expire_datetime()
+).
+
+-type(option_subscription_include_body() ::
+  {Key   :: 'include_body',
+   Value :: boolean()}
+).
+
+-type(option_subscription_show_values() ::
+  {Key   :: 'show-values',
+   Value :: ['away' | 'chat' | 'dnd' | 'online' | 'xa']}
+).
+
+-type(option_subscription_subscription_type() ::
+  {Key   :: 'subscription_type',
+   Value :: 'all' | 'items' | 'nodes'}
+).
+
+-type(option_subscription_subscription_depth() ::
+  {Key   :: 'subscription_depth',
+   Value :: 'all' | exmpp_pubsub:level()}
+).
+
+
+-export_type([
+  option_subscription/0,
+  %%
+  option_subscription_leaf/0,
+  option_subscription_collection/0,
+  %%
+  option_subscription_leaf_local/0,
+  option_subscription_leaf_remote/0,
+  %%
+  option_subscription_collection_local/0,
+  option_subscription_collection_remote/0
+]).
+
+%%
+-type(option_subscription_leaf_local()
+  :: pubsub_options:option_subscription_deliver()
+   | pubsub_options:option_subscription_expire()
+ % | pubsub_options:option_subscription_include_body()
+   | pubsub_options:option_subscription_show_values()
+).
+
+%%
+-type(option_subscription_leaf_remote()
+  :: pubsub_options:option_subscription_deliver()
+ % | pubsub_options:option_subscription_expire_datetime()
+ % | pubsub_options:option_subscription_include_body()
+).
+
+%%
+-type(option_subscription_collection_local()
+  :: pubsub_options:option_subscription_deliver()
+   | pubsub_options:option_subscription_expire()
+   | pubsub_options:option_subscription_expire_presence()
+   | pubsub_options:option_subscription_expire_datetime()
+  %| pubsub_options:option_subscription_include_body()
+   | pubsub_options:option_subscription_show_values()
+   | pubsub_options:option_subscription_subscription_type()
+   | pubsub_options:option_subscription_subscription_depth()
+).
+
+%%
+-type(option_subscription_collection_remote()
+  :: pubsub_options:option_subscription_deliver()
+   | pubsub_options:option_subscription_expire_datetime()
+   | pubsub_options:option_subscription_include_body()
+   | pubsub_options:option_subscription_subscription_type()
+   | pubsub_options:option_subscription_subscription_depth()
+).
+
+%%
+-type(option_subscription_leaf()
+  :: pubsub_options:option_subscription_leaf_local()
+   | pubsub_options:option_subscription_leaf_remote()
+).
+
+%%
+-type(option_subscription_collection()
+  :: pubsub_options:option_subscription_collection_local()
+   | pubsub_options:option_subscription_collection_remote()
+).
+
+
+%%
+-type(option_subscription()
+  :: pubsub_options:option_subscription_leaf()
+   | pubsub_options:option_subscription_collection()
+).
+
+
+-export_type([
+  options_subscription/0,
+  %%
+  options_subscription_leaf/0,
+  options_subscription_collection/0,
+  %%
+  options_subscription_local/0,
+  options_subscription_remote/0,
+  %%
+  options_subscription_leaf_local/0,
+  options_subscription_leaf_remote/0,
+  %%
+  options_subscription_collection_local/0,
+  options_subscription_collection_remote/0
+]).
+
+%%
+-type(options_subscription_leaf_local()
+  :: [pubsub_options:options_subscription_leaf_local(),...]
+).
+
+%%
+-type(options_subscription_leaf_remote()
+  :: [pubsub_options:options_subscription_leaf_remote(),...]
+).
+
+%%
+-type(options_subscription_collection_local()
+  :: [pubsub_options:options_subscription_collection_local(),...]
+).
+
+%%
+-type(options_subscription_collection_remote()
+  :: [pubsub_options:options_subscription_collection_remote(),...]
+).
+
+%%
+-type(options_subscription_leaf()
+  :: pubsub_options:options_subscription_leaf_local()
+   | pubsub_options:options_subscription_leaf_remote()
+).
+
+%%
+-type(options_subscription_collection()
+  :: pubsub_options:options_subscription_collection_local()
+   | pubsub_options:options_subscription_collection_remote()
+).
+
+%%
+-type(options_subscription_local()
+  :: pubsub_options:options_subscription_leaf_local()
+   | pubsub_options:options_subscription_collection_local()
+).
+
+%%
+-type(options_subscription_remote()
+  :: pubsub_options:options_subscription_leaf_remote()
+   | pubsub_options:options_subscription_collection_remote()
+).
+
+-type(options_subscription()
+  :: pubsub_options:options_subscription_leaf()
+   | pubsub_options:options_subscription_collection()
+).
+
+%% --------------------------------------------------------------------
+%% Functions.
+%% --------------------------------------------------------------------
+
+
+xmlns(Xmlel) ->
+    get_tag_attr_s(<<"xmlns">>, Xmlel).
+
+
+-define(Is_Xmlel_Field(Xmlel),
+(
+  Xmlel#xmlel.name == <<"field">>
+)).
+
+-define(Is_Xmlel_Value(Xmlel),
+(
+  Xmlel#xmlel.name  == <<"value">>         andalso
+  Xmlel#xmlel.attrs == []
+)).
+
+-define(Is_Xmlel_X(Xmlel),
+(
+  Xmlel#xmlel.name  == <<"x">>
+)).
+
+-define(Is_Xmlel_X_Submit(Xmlel),
+(
+  %Xmlel#xmlel.ns    == 'jabber:x:data' andalso
+  Xmlel#xmlel.name  == <<"x">>           % andalso
+ % Xmlel#xmlel.attrs == [#xmlattr{name = <<"type">>, value = <<"submit">>}]
+)).
+
+-define(Is_Xmlel_X_Form(Xmlel),
+(
+  %Xmlel#xmlel.ns    == 'jabber:x:data' andalso
+  Xmlel#xmlel.name  == <<"x">>             andalso
+  Xmlel#xmlel.attrs == [{<<"type">>, <<"form">>}]
+)).
+
+
+
+%%
+%%
+-define(Is_Default_Subscribe_Option(Option),
+(
+  Option == {'deliver', true}
+      orelse
+  Option == {'expire', undefined}
+      orelse
+  Option == {'include_body', false}
+      orelse
+  Option == {'show-values', ['away' , 'chat' , 'dnd' , 'online' , 'xa']}
+)).
+
+
+%%
+-spec(trim_subscription_options/1 ::
+(
+  Subscription_Options::pubsub_options:options_subscription())
+    -> Subscription_Options::pubsub_options:options_subscription()
+).
+
+trim_subscription_options(Subscription_Options) ->
+    trim_subscription_options(Subscription_Options, []).
+
+%%
+-spec(trim_subscription_options/2 ::
+(
+  Options              :: [] | pubsub_options:options_subscription(),
+  Subscription_Options :: [] | pubsub_options:options_subscription())
+    -> Subscription_Options :: [] | pubsub_options:options_subscription()
+).
+
+trim_subscription_options([] = _Options, Subscription_Options) ->
+    Subscription_Options;
+%%
+trim_subscription_options([Option | Options], Subscription_Options)
+  when ?Is_Default_Subscribe_Option(Option) ->
+    trim_subscription_options(Options, Subscription_Options);
+%%
+trim_subscription_options([Option | Options], Subscription_Options) ->
+    trim_subscription_options(Options, [Option | Subscription_Options]).
+
+%%
+-spec(parse_xmlel_x/5 ::
+(
+  Plugin          :: exmpp_pubsub:plugin(),
+  Pubsub_Features :: exmpp_pubsub:pubsub_features(),
+  Entity          :: xmpp_jid:usr_entity(),
+  Form_Type       :: 'node_config' | 'publish-options',
+  Xmlels          :: [Xmlel_X::xmlel(),...]
+                   | [Xmlel::xmlel()]
+                   | [])
+    -> {ok,
+        Options :: pubsub_options:options_node()
+                 | pubsub_options:options_item()}
+    %%%
+     | {error, 'not-acceptable'}
+     | {error, 'feature-not-implemented', 'collections'}
+    %%%
+     | {error, 'invalid-options'}
+     | {error, 'jid-malformed'}
+     %
+     | {error, 'not-acceptable'}
+     | {error, 'not-acceptable', 'unsupported-access-model'}
+     %
+     | {error, 'feature-not-implemented', 'collections'}
+     | {error, 'feature-not-implemented', 'multi-collections'}
+).
+
+parse_xmlel_x(Plugin, _Pubsub_Features, _Entity, 'node_config', []) ->
+    {ok, Plugin:node_options('leaf')};
+parse_xmlel_x(_Plugin, _Pubsub_Features, _Entity, 'publish-options', []) ->
+    {ok, []};
+%%
+parse_xmlel_x(Plugin, Pubsub_Features, {U,S,_} = _Entity, Form_Type, [Xmlel_X])
+  when ?Is_Xmlel_X(Xmlel_X) ->
+    case
+        {xmlns(Xmlel_X),
+         options_type(remove_cdata(Xmlel_X#xmlel.children), Pubsub_Features)}
+    of
+        {?NS_XDATA, {ok, 'node_config' = Form_Type, Node_Type, Xmlels}} ->
+            parse_xmlels_field(Form_Type, Node_Type, Pubsub_Features,
+                {U,S,undefined}, Xmlels, Plugin:node_options(Node_Type));
+        %%
+        {?NS_XDATA, {ok, 'publish-options' = Form_Type, Node_Type, Xmlels}} ->
+            parse_xmlels_field(Form_Type, Node_Type, Pubsub_Features,
+                {U,S,undefined}, Xmlels, Plugin:item_options());
+        %%
+        {?NS_XDATA, Error} ->
+            Error;
+        _ ->
+            {error, 'invalid-options'}
+    end;
+parse_xmlel_x(_Plugin, _Pubsub_Features, _Entity, _Form_Type, _Xmlels) ->
+    {error, 'invalid-options'}.
+
+%%
+-spec(parse_xmlel_x/7 ::
+(
+  Plugin          :: exmpp_pubsub:plugin(),
+  Pubsub_Features :: exmpp_pubsub:pubsub_features(),
+  Entity          :: xmpp_jid:usr_entity(),
+  Entity_Type     :: 'local' | 'remote',
+  Form_Type       :: 'subscribe_options',
+  Node_Type       :: 'leaf' | 'collection',
+  Xmlels          :: [Xmlel_X::xmlel(),...]
+                   | [Xmlel::xmlel()]
+                   | [])
+    -> {ok,
+        Subscription_Options :: [] | pubsub_options:options_subscription_leaf()}
+    %%%
+     | {error, 'invalid-options'}
+     | {error, 'not-acceptable'}
+).
+
+parse_xmlel_x(Plugin, _Pubsub_Features, _Entity, Entity_Type, 'subscribe_options',
+  Node_Type, []) ->
+    {ok, Plugin:subscription_options(Entity_Type, Node_Type)};
+%%
+parse_xmlel_x(Plugin, Pubsub_Features, {U,S,_} = _Entity, Entity_Type,
+  'subscribe_options' = Form_Type, Node_Type, [Xmlel_X])
+  when ?Is_Xmlel_X(Xmlel_X) ->
+    case
+        {xmlns(Xmlel_X),
+         options_type(remove_cdata(Xmlel_X#xmlel.children), 'subscribe_options', [])}
+    of
+        {?NS_XDATA, {ok, 'subscribe_options', Xmlels}} ->
+            parse_xmlels_field(Form_Type, Node_Type, Pubsub_Features,
+                {U,S,undefined}, Entity_Type, Xmlels,
+                Plugin:default_subscription_options(Entity_Type, Node_Type));
+        {?NS_XDATA, Error} ->
+            Error;
+        _ ->
+            {error, 'invalid-options'}
+    end;
+%%
+parse_xmlel_x(_Plugin, _Pubsub_Features, _Entity, _Entity_Type, 'subscribe_options',
+  _Node_Type, _Xmlels) ->
+    {error, 'invalid-options'}.
+
+%%
+-spec(options_type/3 ::
+(
+  Xmlels        :: [Xmlel_Field::xmlel()]
+                 | [Xmlel::xmlel()],
+  Form_Type     :: 'subscribe_options',
+  Xmlels_Fields :: [Xmlel_Field::xmlel()]
+                 | [Xmlel::xmlel()])
+    -> {ok,
+        Form_Type    :: 'subscribe_options',
+        Xmlels_Field :: [Xmlel_Field::xmlel()]
+                      | [Xmlel::xmlel()]}
+    %%%
+     | {error, 'not-acceptable'}
+).
+
+options_type([] = _Xmlels_Field, 'subscribe_options', _Xmlels) ->
+    {error, 'not-acceptable'};
+%%
+options_type([Xmlel_Field | Xmlels_Field], 'subscribe_options', Xmlels)
+  when ?Is_Xmlel_Field(Xmlel_Field) ->
+    case {xmlns(Xmlel_Field), get_tag_attr_s(<<"var">>, Xmlel_Field)} of
+        {_, <<>>} ->
+            {error, 'not-acceptable'};
+        {?NS_XDATA, <<"FORM_TYPE">>} ->
+            case remove_cdata(Xmlel_Field#xmlel.children) of
+                [Xmlel_Value] when ?Is_Xmlel_Value(Xmlel_Value) ->
+                    case {xmlns(Xmlel_Value), get_tag_cdata(Xmlel_Value)} of
+                        {?NS_XDATA, ?NS_PUBSUB_SUBSCRIBE_OPTIONS} ->
+                            {ok, 'subscribe_options', Xmlels ++ Xmlels_Field};
+                        _ ->
+                            {error, 'not-acceptable'}
+                    end;
+                _ ->
+                    {error, 'not-acceptable'}
+            end;
+        {?NS_XDATA, _} ->
+            options_type(Xmlels_Field, 'subscribe_options',
+                [Xmlel_Field | Xmlels]);
+        _ ->
+            {error, 'not-acceptable'}
+    end.
+
+%%
+-spec(options_type/2 ::
+(
+  Xmlels          :: [Xmlel_Field::xmlel()]
+                   | [Xmlel::xmlel()],
+  Pubsub_Features :: exmpp_pubsub:pubsub_features())
+    -> {ok,
+        Form_Type    :: 'node_config' | 'publish-options',
+        Node_Type    :: 'leaf' | 'collection',
+        Xmlels_Field :: [Xmlel_Field::xmlel()]
+                      | [Xmlel::xmlel()]}
+    %%%
+     | {error, 'not-acceptable'}
+     | {error, 'feature-not-implemented', 'collections'}
+).
+
+options_type(Xmlels, Pubsub_Features) ->
+    options_type(Xmlels,
+        lists:member(<<"collections">>, Pubsub_Features), undefined, undefined, []).
+
+%%
+-spec(options_type/5 ::
+(
+  Xmlels        :: [Xmlel_Field::xmlel()]
+                 | [Xmlel::xmlel()],
+  Collections   :: boolean(),
+  Form_Type     :: undefined | 'node_config' | 'publish-options',
+  Node_Type     :: undefined | 'leaf' | 'collection',
+  Xmlels_Fields :: [Xmlel_Field::xmlel()]
+                 | [Xmlel::xmlel()])
+    -> {ok,
+        Form_Type    :: 'node_config' | 'publish-options',
+        Node_Type    :: 'leaf' | 'collection',
+        Xmlels_Field :: [Xmlel_Field::xmlel()]
+                      | [Xmlel::xmlel()]}
+    %%%
+     | {error, 'not-acceptable'}
+     | {error, 'feature-not-implemented', 'collections'}
+).
+
+options_type([] = _Xmlels, _Collections, Form_Type, undefined = _Node_Type,
+  Xmlels_Field)
+  when Form_Type =/= undefined ->
+    {ok, Form_Type, 'leaf', Xmlels_Field};
+%%
+options_type([] = _Xmlels, _Collections, Form_Type, Node_Type, Xmlels_Field)
+  when Form_Type =/= undefined ->
+    {ok, Form_Type, Node_Type, Xmlels_Field};
+%%
+options_type([] = _Xmlels, _Collections, undefined = _Form_Type, _Node_Type,
+  _Xmlels_Field) ->
+    {error, 'bad-options'};
+%%
+options_type(Xmlels, _Collections, Form_Type, Node_Type, Xmlels_Field)
+  when Form_Type =/= undefined andalso Node_Type =/= undefined ->
+    {ok, Form_Type, Node_Type, Xmlels ++ Xmlels_Field};
+%%
+options_type([Xmlel_Field | Xmlels_Field], Collections, Form_Type, Node_Type,
+  Xmlels)
+  when ?Is_Xmlel_Field(Xmlel_Field) ->
+    case {xmlns(Xmlel_Field), get_tag_attr_s(<<"var">>, Xmlel_Field)} of
+        {_, <<>>} ->
+            {error, 'not-acceptable'};
+        {?NS_XDATA, <<"FORM_TYPE">>} ->
+            case remove_cdata(Xmlel_Field#xmlel.children) of
+                [Xmlel_Value] when ?Is_Xmlel_Value(Xmlel_Value) ->
+                    case {xmlns(Xmlel_Value), get_tag_cdata(Xmlel_Value)} of
+                        {?NS_XDATA, ?NS_PUBSUB_NODE_CONFIG} ->
+                            options_type(Xmlels_Field, Collections, 'node_config',
+                                Node_Type, Xmlels);
+                        {?NS_XDATA, ?NS_PUBSUB_PUBLISH_OPTIONS} ->
+                            options_type(Xmlels_Field, Collections,
+                                'publish-options', Node_Type, Xmlels);
+                        _ ->
+                            {error, 'not-acceptable'}
+                    end;
+                _ ->
+                    {error, 'not-acceptable'}
+            end;
+        {?NS_XDATA, <<"pubsub#node_type">>} ->
+            case remove_cdata(Xmlel_Field#xmlel.children) of
+                [Xmlel_Value] when ?Is_Xmlel_Value(Xmlel_Value) ->
+                    case {xmlns(Xmlel_Value), get_tag_cdata(Xmlel_Value)} of
+                        {?NS_XDATA, <<"leaf">>} ->
+                            options_type(Xmlels_Field, Collections, Form_Type,
+                                'leaf', Xmlels);
+                        {?NS_XDATA, <<"collection">>} ->
+                            case Collections of
+                                true ->
+                                    options_type(Xmlels_Field, Collections,
+                                        Form_Type, 'collection', Xmlels);
+                                false ->
+                                    {error,
+                                     'feature-not-implemented', 'collections'}
+                            end;
+                        _ ->
+                            {error, 'not-acceptable'}
+                    end
+            end;
+        {?NS_XDATA, _Xmlattr} ->
+            options_type(Xmlels_Field, Collections, Form_Type, Node_Type,
+                [Xmlel_Field | Xmlels]);
+        _ ->
+            {error, 'not-acceptable'}
+    end.
+
+%%
+-spec(parse_xmlels_field/6 ::
+(
+  Options_Type    :: 'node_config' | 'publish-options',
+  Node_Type       :: 'leaf' | 'collection',
+  Pubsub_Features :: exmpp_pubsub:pubsub_features(),
+  Entity          :: xmpp_jid:usr_entity(),
+  Xmlels          :: [Xmlel_Field::xmlel()]
+                   | [Xmlel::xmlel()],
+  Options         :: pubsub_options:options_node()
+                   | pubsub_options:options_item()
+                   %%
+                   | {error, 'invalid-options'}
+                   | {error, 'jid-malformed'}
+                   %
+                   | {error, 'not-acceptable'}
+                   | {error, 'not-acceptable', 'unsupported-access-model'}
+                   %
+                   | {error, 'feature-not-implemented', 'collections'}
+                   | {error, 'feature-not-implemented', 'multi-collections'})
+    -> {ok,
+        Options :: pubsub_options:options_node()
+                 | pubsub_options:options_item()}
+    %%%
+     | {error, 'invalid-options'}
+     | {error, 'jid-malformed'}
+     %
+     | {error, 'not-acceptable'}
+     | {error, 'not-acceptable', 'unsupported-access-model'}
+     %
+     | {error, 'feature-not-implemented', 'collections'}
+     | {error, 'feature-not-implemented', 'multi-collections'}
+).
+
+%%
+parse_xmlels_field(_Options_Type, _Node_Type, _Pubsub_Features, _Entity,
+  _Xmlels, Error)
+  when is_tuple(Error) ->
+    Error;
+parse_xmlels_field(_Options_Type, _Node_Type, _Pubsub_Features, _Entity,
+  [] = _Xmlels, Options) ->
+    {ok, Options};
+%%
+parse_xmlels_field(Options_Type, Node_Type, Pubsub_Features, Entity,
+  [Xmlel_Field | Xmlels], Options)
+  when ?Is_Xmlel_Field(Xmlel_Field) ->
+    case xmlns(Xmlel_Field) of
+        ?NS_XDATA ->
+            parse_xmlels_field(Options_Type, Node_Type, Pubsub_Features, Entity,
+                Xmlels,
+                parse_xmlel_field_attrs(
+                    get_tag_attr_s(<<"var">>, Xmlel_Field),
+                    Options_Type, Node_Type, Pubsub_Features, Entity,
+                    remove_cdata(Xmlel_Field#xmlel.children),
+                    Options));
+        _ ->
+            {error, 'invalid-options'}
+    end;
+%%
+parse_xmlels_field(_Options_Type, _Node_Type, _Pubsub_Feature, _Entity,
+  _Xmlels, _Options) ->
+    {error, 'invalid-options'}.
+
+%%
+-spec(parse_xmlels_field/7 ::
+(
+  Options_Type    :: 'subscribe_options',
+  Node_Type       :: 'leaf' | 'collection',
+  Pubsub_Features :: exmpp_pubsub:pubsub_features(),
+  Entity          :: xmpp_jid:usr_entity(),
+  Entity_Type     :: 'local' | 'remote',
+  Xmlels          :: [Xmlel_Field::xmlel()]
+                   | [Xmlel::xmlel()],
+  Options         :: pubsub_options:options_subscription()
+                   %
+                   | {error, 'invalid-options'}
+                   | {error, 'not-acceptable'})
+    -> {ok,
+        Options :: pubsub_options:options_node()
+                 | pubsub_options:options_item()}
+    %%%
+     | {error, 'invalid-options'}
+     | {error, 'not-acceptable'}
+).
+
+%%
+parse_xmlels_field(_Options_Type, _Node_Type, _Pubsub_Features, _Entity,
+  _Entity_Type, _Xmlels, Error)
+  when is_tuple(Error) ->
+    Error;
+parse_xmlels_field(_Options_Type, _Node_Type, _Pubsub_Features, _Entity,
+  _Entity_Type, [] = _Xmlels, Options) ->
+    {ok, trim_subscription_options(Options)};
+%%
+parse_xmlels_field(Options_Type, Node_Type, Pubsub_Features, Entity,
+  Entity_Type, [Xmlel_Field | Xmlels], Options)
+  when ?Is_Xmlel_Field(Xmlel_Field) ->
+    case xmlns(Xmlel_Field) of
+        ?NS_XDATA ->
+            parse_xmlels_field(Options_Type, Node_Type, Pubsub_Features, Entity,
+                Entity_Type,
+                Xmlels,
+                parse_xmlel_field_attrs(
+                    get_tag_attr_s(<<"var">>, Xmlel_Field),
+                    Options_Type, Node_Type, Pubsub_Features, Entity, Entity_Type,
+                    remove_cdata(Xmlel_Field#xmlel.children),
+                    Options));
+        _ ->
+            {error, 'invalid-options'}
+    end;
+%%
+parse_xmlels_field(_Options_Type, _Node_Type, _Pubsub_Feature, _Entity,
+  _Entity_Type, _Xmlels, _Options) ->
+    {error, 'invalid-options'}.
+
+%%
+-spec(parse_xmlel_field_attrs/7 ::
+(
+  Pubsub_Option   :: binary(),
+  Options_Type    :: 'node_config' | 'publish-options',
+  Node_Type       :: 'leaf' | 'collection',
+  Pubsub_Features :: exmpp_pubsub:pubsub_features(),
+  Entity          :: xmpp_jid:usr_entity(),
+  Xmlels          :: [Xmlel_Value::xmlel(),...]
+                   | [Xmlel::xmlel(),...],
+  Options         :: pubsub_options:options_node()
+                   | pubsub_options:options_item())
+    -> Options :: pubsub_options:options_node()
+                | pubsub_options:options_item()
+    %%%
+     | {error, 'invalid-options'}
+     | {error, 'jid-malformed'}
+     %
+     | {error, 'not-acceptable'}
+     | {error, 'not-acceptable', 'unsupported-access-model'}
+     %
+     | {error, 'feature-not-implemented', 'collections'}
+     | {error, 'feature-not-implemented', 'multi-collections'}
+).
+
+parse_xmlel_field_attrs(<<"pubsub#roster_groups_allowed">>, Options_Type,
+  Node_Type, Pubsub_Features, Entity, Xmlels, Options)
+  when (Options_Type == 'node_config' orelse Options_Type == 'publish-options')
+  andalso (Node_Type == 'leaf' orelse Node_Type == 'collection') ->
+    case lists:member(<<"access-roster">>, Pubsub_Features) of
+        true ->
+            case
+                case Options_Type of
+                    'node_config' ->
+                        parse_pubsub_option_node(<<"roster_groups_allowed">>,
+                            Node_Type, Pubsub_Features, Xmlels);
+                    'publish-options' ->
+                        parse_pubsub_option_item(<<"roster_groups_allowed">>,
+                            Pubsub_Features, Xmlels)
+                end
+                
+            of
+                {ok, Roster_Groups_Allowed} ->
+                    case lists:keyfind('roster_groups_allowed', 1, Options) of
+                        false ->
+                            [{Entity, Roster_Groups_Allowed} | Options];
+                        {'roster_groups_allowed', Rosters_Groups_Allowed} ->
+                            lists:keyreplace('roster_groups_allowed', 1, Options,
+                                {'roster_groups_allowed',
+                                 _New_Rosters_Groups_Allowed =
+                                 case
+                                     lists:keyreplace(Entity, 1,
+                                         Rosters_Groups_Allowed,
+                                         {Entity, Roster_Groups_Allowed})
+                                 of
+                                     Rosters_Groups_Allowed ->
+                                         [{Entity, Roster_Groups_Allowed}
+                                         | Rosters_Groups_Allowed];
+                                     New_Rosters_Groups_Allowed ->
+                                         New_Rosters_Groups_Allowed
+                                 end})
+                    end;
+                Error ->
+                    Error
+            end;
+        false ->
+            {error, 'invalid-options'}
+    end;
+%%
+parse_xmlel_field_attrs(<<"pubsub#", Pubsub_Option/binary>>,
+  'node_config' = _Options_Type, Node_Type, Pubsub_Features, _Entity, Xmlels,
+  Node_Options) ->
+    case
+        lists:keymember(
+            Key = list_to_atom(binary_to_list(Pubsub_Option)), 1, Node_Options)
+    of
+        true ->
+            case
+                parse_pubsub_option_node(Pubsub_Option, Node_Type,
+                    Pubsub_Features, Xmlels)
+            of
+                {ok, Value} ->
+                    lists:keyreplace(Key, 1, Node_Options, {Key, Value});
+                Error ->
+                    Error
+            end;
+        false ->
+            Node_Options%{error, 'invalid-options'}
+    end;
+%%
+parse_xmlel_field_attrs(<<"pubsub#", Pubsub_Option/binary>>,
+  'publish-options' = _Options_Type, _Node_Type, Pubsub_Features, _Entity, Xmlels,
+  Item_Options) ->
+    case parse_pubsub_option_item(Pubsub_Option, Pubsub_Features, Xmlels) of
+        {ok, Value}
+          when   Value == undefined
+          orelse Value == [] ->
+            lists:keydelete(_Key = list_to_atom(binary_to_list(Pubsub_Option)),
+                1, Item_Options);
+        {ok, Value} ->
+            Key = list_to_atom(binary_to_list(Pubsub_Option)),
+            case lists:keyreplace(Key, 1, Item_Options, {Key, Value}) of
+                Item_Options     -> [{Key, Value} | Item_Options];
+                New_Item_Options -> New_Item_Options
+            end;
+        Error ->
+            Error
+    end;
+%%
+parse_xmlel_field_attrs(_Xmlattr_value, _Options_Type, _Node_Type,
+  _Pubsub_Features, _Entity, _Xmlels, _Options) ->
+    {error, 'invalid-options'}.
+
+%%
+-spec(parse_xmlel_field_attrs/8 ::
+(
+  Pubsub_Option   :: binary(),
+  Options_Type    :: 'subscribe_options',
+  Node_Type       :: 'leaf' | 'collection',
+  Pubsub_Features :: exmpp_pubsub:pubsub_features(),
+  Entity          :: xmpp_jid:usr_entity(),
+  Entity_Type     :: 'local' | 'remote',
+  Xmlels          :: [Xmlel_Value::xmlel(),...]
+                   | [Xmlel::xmlel(),...],
+  Subscription_Options :: pubsub_options:options_subscription())
+    -> Subscription_Options :: pubsub_options:options_subscription()
+    %%%
+     | {error, 'invalid-options'}
+).
+
+parse_xmlel_field_attrs(<<"pubsub#", Pubsub_Option/binary>>,
+  'subscribe_options' = _Options_Type, Node_Type, Pubsub_Features, _Entity,
+  Entity_Type, Xmlels, Subscription_Options) ->
+    case
+        lists:keymember(Key = list_to_atom(binary_to_list(Pubsub_Option)), 1,
+            Subscription_Options)
+    of
+        true ->
+            case
+                parse_pubsub_option_subscription(Pubsub_Option, Node_Type,
+                    Entity_Type, Pubsub_Features, Xmlels)
+            of
+                {ok, Value}
+                  when ?Is_Default_Subscribe_Option({Key, Value}) ->
+                    lists:keydelete(Key, 1, Subscription_Options);
+                {ok, Value} ->
+                    lists:keyreplace(Key, 1, Subscription_Options, {Key, Value});
+                Error ->
+                    Error
+            end;
+        false ->
+            {error, 'invalid-options'}
+    end;
+%%
+parse_xmlel_field_attrs(_Xmlattr_value, _Options_Type, _Node_Type,
+  _Pubsub_Features, _Entity, _Entity_Type, _Xmlels, _Options) ->
+    {error, 'invalid-options'}.
+
+
+%%
+%%
+-spec(parse_pubsub_option_node/4 ::
+(
+  Pubsub_Option   :: binary(),
+  Node_Type       :: 'collection' | 'leaf',
+  Pubsub_Features :: exmpp_pubsub:pubsub_features(),
+  Xmlels          :: [Xmlel_Value::xmlel()]
+                   | [Xmlel::xmlel()])
+    -> {ok, Access_Model                   :: pubsub_options:access_model()}
+   % | {ok, Body_XSLT                      :: undefined | binary()}
+     | {ok, Children_Association_Policy    :: 'all' | 'owners' | 'whitelist'}
+     | {ok, Children_Association_Whitelist :: [Jid::xmpp_jid:raw_jid_entity_bare()]}
+     | {ok, Children                       :: [Child_NodeId::exmpp_pubsub:nodeId()]}
+     | {ok, Children_Max                   :: undefined | non_neg_integer()}
+     | {ok, Collection                     :: [Parent_NodeId::exmpp_pubsub:nodeId()]}
+     | {ok, Contact                        :: [Jid::xmpp_jid:raw_jid_entity()]}
+   % | {ok, Dataform_XSLT                  :: undefined | binary()}
+     | {ok, Deliver_Notifications          :: boolean()}
+     | {ok, Deliver_Payloads               :: boolean()}
+     | {ok, Description                    :: undefined | binary()}
+     | {ok, Item_Expire                    :: undefined | non_neg_integer()}
+     | {ok, ItemReply                      :: pubsub_options:item_reply()}
+     | {ok, Language                       :: undefined | binary()}
+     | {ok, Max_Items                      :: undefined | non_neg_integer()}
+     | {ok, Max_Payload_Size               :: undefined | non_neg_integer()}
+     | {ok, Node_Type                      :: pubsub_options:node_type()}
+     | {ok, Notification_Type              :: pubsub_options:notification_type()}
+     | {ok, Notify_Config                  :: boolean()}
+     | {ok, Notify_Delete                  :: boolean()}
+     | {ok, Notify_Retract                 :: boolean()}
+     | {ok, Notify_Sub                     :: boolean()}
+     | {ok, Persist_Items                  :: boolean()}
+     | {ok, Presence_Based_Delivery        :: boolean()}
+     | {ok, Publish_Model                  :: pubsub_options:publish_model()}
+     | {ok, Purge_Offline                  :: boolean()}
+     | {ok, Rosters_Groups_Allowed         :: pubsub_options:rosters_groups_allowed()}
+     | {ok, Send_Last_Published_Item       :: pubsub_options:send_last_published_item()}
+     | {ok, Tempsub                        :: boolean()}
+     | {ok, Subscribe                      :: boolean()}
+     | {ok, Title                          :: undefined | binary()}
+     | {ok, Type                           :: undefined | atom()}
+    %%%
+     | {error, 'invalid-options'}
+     | {error, 'jid-malformed'}
+     %
+     | {error, 'not-acceptable'}
+     | {error, 'not-acceptable', 'unsupported-access-model'}
+     %
+     | {error, 'feature-not-implemented', 'collections'}
+     | {error, 'feature-not-implemented', 'multi-collections'}
+).
+
+parse_pubsub_option_node(<<"access_model">> = _Pubsub_Option, Node_Type,
+  Pubsub_Features, Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    parse_xmlel_value({'access_model', Pubsub_Features}, Xmlels);
+%%
+%%parse_pubsub_option_node(<<"pubsub#body_xslt">> = _Pubsub_Option,
+%% 'leaf' = _Node_Type, Pusbub_Features, Xmlels) ->
+%%    case lists:member(<<"publish">>, Pubsub_Features) of
+%%        true ->
+%%            parse_xmlel_value('text-single', Xmlels);
+%%        false ->
+%%            {error, 'invalid-options'}
+%%    end;
+%%
+parse_pubsub_option_node(<<"children_association_policy">> = _Pubsub_Option,
+  'collection' = _Node_Type, _Pubsub_Features, Xmlels) ->
+    parse_xmlel_value({'list-single', 'atom',
+        _Default_Values = ['all', 'owners', 'whitelist']}, Xmlels);
+%%
+parse_pubsub_option_node(<<"children_association_whitelist">> = _Pubsub_Option,
+  'collection' = _Node_Type, _Pubsub_Features, [] = _Xmlels) ->
+    {ok, []};
+parse_pubsub_option_node(<<"children_association_whitelist">> = _Pubsub_Option,
+  'collection' = _Node_Type, _Pubsub_Features, Xmlels) ->
+    parse_xmlel_value({'jid-multi', 'bare'}, Xmlels);
+%%
+%%
+parse_pubsub_option_node(<<"children">> = _Pubsub_Option,
+  'collection' = _Node_Type, _Pubsub_Features, [] = Xmlels) ->
+     parse_xmlel_value('text-multi', Xmlels);
+parse_pubsub_option_node(<<"children">> = _Pubsub_Option,
+  'collection' = _Node_Type, _Pubsub_Features, [_] = Xmlels) ->
+     parse_xmlel_value('text-multi', Xmlels);
+parse_pubsub_option_node(<<"children">> = _Pubsub_Option,
+  'collection' = _Node_Type, Pubsub_Features, Xmlels) ->
+    case lists:member(<<"multi-collections">>, Pubsub_Features) of
+        true  -> parse_xmlel_value('text-multi', Xmlels);
+        false -> {error, 'feature-not-implemented', 'multi-collections'}
+    end;
+%%
+%%
+parse_pubsub_option_node(<<"children_max">> = _Pubsub_Option,
+  'collection' = _Node_Type, _Pubsub_Features, [] = _Xmlels) ->
+    {ok, undefined};
+parse_pubsub_option_node(<<"children_max">> = _Pubsub_Option,
+  'collection' = _Node_Type, Pubsub_Features, [Xmlel_Value])
+  when ?Is_Xmlel_Value(Xmlel_Value) ->
+    case {xmlns(Xmlel_Value), get_tag_cdata(Xmlel_Value)} of
+        {?NS_XDATA, <<>>} ->
+            {ok, undefined};
+        {?NS_XDATA, CData} ->
+            case catch list_to_integer(binary_to_list(CData)) of
+                Integer when Integer == 0 orelse Integer == 1 ->
+                    {ok, Integer};
+                Integer when is_integer(Integer) andalso Integer > 1 ->
+                    case
+                        lists:member(<<"multi-collections">>, Pubsub_Features)
+                    of
+                        true  -> {ok, Integer};
+                        false -> {error, 'not-acceptable'}
+                    end;
+                _ ->
+                    {error, 'not-acceptable'}
+            end;
+        _ ->
+            {error, 'not-acceptable'}
+    end;
+parse_pubsub_option_node(<<"children_max">> = _Pubsub_Option,
+  'collection' = _Node_Type, _Pubsub_Features, _Xmlels) ->
+    {error, 'not-acceptable'};
+%%
+parse_pubsub_option_node(<<"collection">> = _Pubsub_Option, Node_Type,
+  Pubsub_Features, [] = _Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    case lists:member(<<"collections">>, Pubsub_Features) of
+        true  -> {ok, []};
+        false -> {error, 'feature-not-implemented', 'collections'}
+    end;
+parse_pubsub_option_node(<<"collection">> = _Pubsub_Option, Node_Type,
+  Pubsub_Features, [_] = Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    case lists:member(<<"collections">>, Pubsub_Features) of
+        true  -> parse_xmlel_value('text-multi', Xmlels);
+        false -> {error, 'feature-not-implemented', 'collections'}
+    end;
+parse_pubsub_option_node(<<"collection">> = _Pubsub_Option, Node_Type,
+  Pubsub_Features, Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    case lists:member(<<"collections">>, Pubsub_Features) of
+        true ->
+            case lists:member(<<"multi-collections">>, Pubsub_Features) of
+                true  -> parse_xmlel_value('text-multi', Xmlels);
+                false -> {error, 'feature-not-implemented', 'multi-collections'}
+            end;
+        false ->
+            {error, 'feature-not-implemented', 'collections'}
+    end;
+%%
+parse_pubsub_option_node(<<"contact">> = _Pubsub_Option, Node_Type,
+  _Pubsub_Features, [] = _Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    {ok, []};
+parse_pubsub_option_node(<<"contact">> = _Pubsub_Option, Node_Type,
+  _Pubsub_Features, Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    parse_xmlel_value({'jid-multi', 'full'}, Xmlels);
+%%
+%%parse_pubsub_option_node(<<"pubsub#dataform_xslt">> = _Pubsub_Option,
+%% 'leaf' = _Node_Type, Pusbub_Features, Xmlels) ->
+%%    case lists:member(<<"publish">>, Pubsub_Features) of
+%%        true ->
+%%            parse_xmlel_value('text-single', Xmlels);
+%%        false ->
+%%            {error, 'invalid-options'}
+%%    end;
+%%
+parse_pubsub_option_node(<<"deliver_notifications">> = _Pubsub_Option,
+  'leaf' = _Node_Type, Pubsub_Features, Xmlels) ->
+    case lists:member(<<"subscribe">>, Pubsub_Features) of
+        true  -> parse_xmlel_value('boolean', Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_node(<<"deliver_payloads">> = _Pubsub_Option, Node_Type,
+  Pubsub_Features, Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    case lists:member(<<"subscribe">>, Pubsub_Features) of
+        true  -> parse_xmlel_value('boolean', Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_node(<<"description">> = _Pubsub_Option, Node_Type,
+  _Pubsub_Features, [] = _Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    {ok, undefined};
+parse_pubsub_option_node(<<"description">> = _Pubsub_Option, Node_Type,
+  _Pubsub_Features, Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    parse_xmlel_value('text-single', Xmlels);
+%%
+parse_pubsub_option_node(<<"item_expire">> = _Pubsub_Option, 'leaf' = _Node_Type,
+  Pubsub_Features, [] = _Xmlels) ->
+    case lists:member(<<"publish">>, Pubsub_Features) of
+        true  -> {ok, undefined};
+        false -> {error, 'invalid-options'}
+    end;
+parse_pubsub_option_node(<<"item_expire">> = _Pubsub_Option, 'leaf' = _Node_Type,
+  Pubsub_Features, Xmlels) ->
+    case lists:member(<<"publish">>, Pubsub_Features) of
+        true  -> parse_xmlel_value({'text-single', 'integer'}, Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_node(<<"itemreply">> = _Pubsub_Option, 'leaf' = _Node_Type,
+  Pubsub_Features, Xmlels) ->
+    case lists:member(<<"publish">>, Pubsub_Features) of
+        true ->
+            parse_xmlel_value({'list-single', 'atom',
+                _Default_Values = ['owner', 'publisher']}, Xmlels);
+        false ->
+            {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_node(<<"language">> = _Pubsub_Option, Node_Type,
+  _Pubsub_Features, [] = _Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    {ok, undefined};
+parse_pubsub_option_node(<<"language">> = _Pubsub_Option, Node_Type,
+  _Pubsub_Features, Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    parse_xmlel_value('text-single', Xmlels);
+%%
+parse_pubsub_option_node(<<"max_items">> = _Pubsub_Option, 'leaf' = _Node_Type,
+  Pubsub_Features, [] = _Xmlels) ->
+    case lists:member(<<"publish">>, Pubsub_Features) of
+        true  -> {ok, undefined};
+        false -> {error, 'invalid-options'}
+    end;
+parse_pubsub_option_node(<<"max_items">> = _Pubsub_Option, 'leaf' = _Node_Type,
+  Pubsub_Features, Xmlels) ->
+    case lists:member(<<"publish">>, Pubsub_Features) of
+        true  -> parse_xmlel_value({'text-single', 'integer'}, Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_node(<<"max_payload_size">> = _Pubsub_Option,
+  'leaf' = _Node_Type, Pubsub_Features, [] = _Xmlels) ->
+    case lists:member(<<"publish">>, Pubsub_Features) of
+        true  -> {ok, undefined};
+        false -> {error, 'invalid-options'}
+    end;
+parse_pubsub_option_node(<<"max_payload_size">> = _Pubsub_Option,
+  'leaf' = _Node_Type, Pubsub_Features, Xmlels) ->
+    case lists:member(<<"publish">>, Pubsub_Features) of
+        true  -> parse_xmlel_value({'text-single', 'integer'}, Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_node(<<"notification_type">> = _Pubsub_Option, Node_Type,
+  Pubsub_Features, Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    case lists:member(<<"publish">>, Pubsub_Features) of
+        true ->
+            parse_xmlel_value({'list-single', 'atom',
+                _Default_Values = ['headline', 'normal']}, Xmlels);
+        false ->
+            {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_node(<<"notify_config">> = _Pubsub_Option, Node_Type,
+  Pubsub_Features, Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    case lists:member(<<"config-node">>, Pubsub_Features) of
+        true  -> parse_xmlel_value('boolean', Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_node(<<"notify_delete">> = _Pubsub_Option, Node_Type,
+  Pubsub_Features, Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    case lists:member(<<"delete-nodes">>, Pubsub_Features) of
+        true  -> parse_xmlel_value('boolean', Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_node(<<"notify_retract">> = _Pubsub_Option,
+  'leaf' = _Node_Type, Pubsub_Features, Xmlels) ->
+    case lists:member(<<"delete-items">>, Pubsub_Features) of
+        true  -> parse_xmlel_value('boolean', Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_node(<<"notify_sub">> = _Pubsub_Option, Node_Type,
+  Pubsub_Features, Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    case lists:member(<<"subscribe">>, Pubsub_Features) of
+        true  -> parse_xmlel_value('boolean', Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_node(<<"persist_items">> = _Pubsub_Option,
+  'leaf' = _Node_Type, Pubsub_Features,  Xmlels) ->
+    case lists:member(<<"persistent-items">>, Pubsub_Features) of
+        true  -> parse_xmlel_value('boolean', Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_node(<<"presence_based_delivery">> = _Pubsub_Option,
+  Node_Type, Pubsub_Features, Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    case lists:member(<<"presence-notifications">>, Pubsub_Features) of
+        true  -> parse_xmlel_value('boolean', Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_node(<<"publish_model">> = _Pubsub_Option,
+  'leaf' = _Node_Type, Pubsub_Features, Xmlels) ->
+    case lists:member(<<"publish">>, Pubsub_Features) of
+        true ->
+            parse_xmlel_value({'list-single', 'atom',
+                _Default_Values = ['open', 'publishers', 'subscribers']},
+                Xmlels);
+        false ->
+            {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_node(<<"purge_offline">> = _Pubsub_Option,
+  'leaf' = _Node_Type, Pubsub_Features, Xmlels) ->
+    case lists:member(<<"purge-nodes">>, Pubsub_Features) of
+        true  -> parse_xmlel_value('boolean', Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_node(<<"roster_groups_allowed">> = _Pubsub_Option,
+  Node_Type, Pubsub_Features, [] = _Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    case lists:member(<<"access-roster">>, Pubsub_Features) of
+        true  -> {ok, []};
+        false -> {error, 'invalid-options'}
+    end;
+parse_pubsub_option_node(<<"roster_groups_allowed">> = _Pubsub_Option,
+  Node_Type, Pubsub_Features, Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    case lists:member(<<"access-roster">>, Pubsub_Features) of
+        true  -> parse_xmlel_value('list-multi', Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_node(<<"send_last_published_item">> = _Pubsub_Option,
+  'leaf' = _Node_Type, Pubsub_Features, Xmlels) ->
+    case lists:member(<<"last-published">>, Pubsub_Features) of
+        true ->
+            parse_xmlel_value({'list-single', 'atom',
+                _Default_Values = case
+                    lists:member(<<"presence-notifications">>, Pubsub_Features)
+                of
+                    true  -> ['never', 'on_sub', 'on_sub_and_presence'];
+                    false -> ['never', 'on_sub']
+                end},
+                Xmlels);
+        false ->
+            {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_node(<<"tempsub">> = _Pubsub_Option, Node_Type,
+  Pubsub_Features, Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    case lists:member(<<"subscribe">>, Pubsub_Features) of
+        true ->
+            case lists:member(<<"presence-notifications">>, Pubsub_Features) of
+                true  -> parse_xmlel_value('boolean', Xmlels);
+                false -> {error, 'invalid-options'}
+            end;
+        false ->
+            {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_node(<<"subscribe">> = _Pubsub_Option, Node_Type,
+  Pubsub_Features, Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    case lists:member(<<"subscribe">>, Pubsub_Features) of
+        true  -> parse_xmlel_value('boolean', Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_node(<<"title">> = _Pubsub_Option, Node_Type,
+  _Pubsub_Features, [] = _Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    {ok, undefined};
+parse_pubsub_option_node(<<"title">> = _Pubsub_Option, Node_Type,
+  _Pubsub_Features, Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    parse_xmlel_value('text-single', Xmlels);
+%%
+parse_pubsub_option_node(<<"type">> = _Pubsub_Option,
+  'leaf' = _Node_Type, Pubsub_Features, [] = _Xmlels) ->
+    case lists:member(<<"publish">>, Pubsub_Features) of
+        true  -> {ok, undefined};
+        false -> {error, 'invalid-options'}
+    end;
+parse_pubsub_option_node(<<"type">> = _Pubsub_Option,
+  'leaf' = _Node_Type, Pubsub_Features, Xmlels) ->
+    case lists:member(<<"publish">>, Pubsub_Features) of
+        true  -> parse_xmlel_value({'text-single', 'atom'}, Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_node(_Pubsub_Option, _Node_Type, _Pubsub_Features, _Xmlels) ->
+    {error, 'invalid-options'}.
+
+%%
+%%
+-spec(parse_pubsub_option_item/3 ::
+(
+  Pubsub_Option   :: binary(),
+  Pubsub_Features :: exmpp_pubsub:pubsub_features(),
+  Xmlels          :: [Xmlel_Value::xmlel()]
+                   | [Xmlel::xmlel()])
+    -> {ok, Access_Model             :: pubsub_options:access_model()}
+   % | {ok, Body_XSLT                :: undefined | binary()}
+   % | {ok, Dataform_XSLT            :: undefined | binary()}
+     | {ok, Deliver_Notifications    :: boolean()}
+     | {ok, Deliver_Payloads         :: boolean()}
+     | {ok, Item_Expire              :: undefined | non_neg_integer()}
+     | {ok, ItemReply                :: pubsub_options:item_reply()}
+%%   | {ok, Max_Payload_Size         :: undefined | non_neg_integer()}
+     | {ok, Notification_Type        :: pubsub_options:notification_type()}
+     | {ok, Notify_Config            :: boolean()}
+     | {ok, Notify_Retract           :: boolean()}
+     | {ok, Persist_Items            :: boolean()}
+     | {ok, Presence_Based_Delivery  :: boolean()}
+%    | {ok, Publish_Model            :: pubsub_options:publish_model()}
+     | {ok, Purge_Offline            :: boolean()}
+     | {ok, Rosters_Groups_Allowed   :: pubsub_options:rosters_groups_allowed()}
+     | {ok, Send_Last_Published_Item :: pubsub_options:send_last_published_item()}
+     | {ok, Type                     :: undefined | atom()}
+    %%%
+     | {error, 'invalid-options'}
+     %
+     | {error, 'not-acceptable'}
+     | {error, 'not-acceptable', 'unsupported-access-model'}
+).
+
+parse_pubsub_option_item(<<"access_model">> = _Pubsub_Option, Pubsub_Features,
+  Xmlels) ->
+    parse_xmlel_value({'access_model', Pubsub_Features}, Xmlels);
+%%
+%%parse_pubsub_option_item(<<"pubsub#body_xslt">> = _Pubsub_Option,
+%%  Pusbub_Features, Xmlels) ->
+%%    case lists:member(<<"publish">>, Pubsub_Features) of
+%%        true ->
+%%            parse_xmlel_value('text-single', Xmlels);
+%%        false ->
+%%            {error, 'invalid-options'}
+%%    end;
+%%
+%%parse_pubsub_option_item(<<"pubsub#dataform_xslt">> = _Pubsub_Option,
+%%  Pusbub_Features, Xmlels) ->
+%%    case lists:member(<<"publish">>, Pubsub_Features) of
+%%        true ->
+%%            parse_xmlel_value('text-single', Xmlels);
+%%        false ->
+%%            {error, 'invalid-options'}
+%%    end;
+%%
+parse_pubsub_option_item(<<"deliver_notifications">> = _Pubsub_Option,
+  Pubsub_Features, Xmlels) ->
+    case lists:member(<<"subscribe">>, Pubsub_Features) of
+        true  -> parse_xmlel_value('boolean', Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_item(<<"deliver_payloads">> = _Pubsub_Option,
+  Pubsub_Features, Xmlels) ->
+    case lists:member(<<"subscribe">>, Pubsub_Features) of
+        true  -> parse_xmlel_value('boolean', Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_item(<<"item_expire">> = _Pubsub_Option, Pubsub_Features,
+  [] = _Xmlels) ->
+    case lists:member(<<"publish">>, Pubsub_Features) of
+        true  -> {ok, undefined};
+        false -> {error, 'invalid-options'}
+    end;
+parse_pubsub_option_item(<<"item_expire">> = _Pubsub_Option, Pubsub_Features,
+  Xmlels) ->
+    case lists:member(<<"publish">>, Pubsub_Features) of
+        true  -> parse_xmlel_value({'text-single', 'integer'}, Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_item(<<"itemreply">> = _Pubsub_Option, Pubsub_Features,
+  Xmlels) ->
+    case lists:member(<<"publish">>, Pubsub_Features) of
+        true ->
+            parse_xmlel_value({'list-single', 'atom',
+                _Default_Values = ['owner', 'publisher']}, Xmlels);
+        false ->
+            {error, 'invalid-options'}
+    end;
+%%
+%parse_pubsub_option_item(<<"max_payload_size">> = _Pubsub_Option,
+%  Pubsub_Features, Xmlels) ->
+%    case lists:member(<<"publish">>, Pubsub_Features) of
+%        true ->
+%            parse_xmlel_value({'text-single', 'integer'}, Xmlels);
+%        false ->
+%            {error, 'invalid-options'}
+%    end;
+%%
+parse_pubsub_option_item(<<"notification_type">> = _Pubsub_Option,
+  Pubsub_Features, Xmlels) ->
+    case lists:member(<<"publish">>, Pubsub_Features) of
+        true ->
+            parse_xmlel_value({'list-single', 'atom',
+                _Default_Values = ['headline', 'normal']}, Xmlels);
+        false ->
+            {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_item(<<"notify_config">> = _Pubsub_Option, Pubsub_Features,
+  Xmlels) ->
+    case lists:member(<<"config-node">>, Pubsub_Features) of
+        true  -> parse_xmlel_value('boolean', Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_item(<<"notify_retract">> = _Pubsub_Option, Pubsub_Features,
+  Xmlels) ->
+    case lists:member(<<"delete-items">>, Pubsub_Features) of
+        true  -> parse_xmlel_value('boolean', Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_item(<<"persist_items">> = _Pubsub_Option, Pubsub_Features,
+  Xmlels) ->
+    case lists:member(<<"persistent-items">>, Pubsub_Features) of
+        true  -> parse_xmlel_value('boolean', Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_item(<<"presence_based_delivery">> = _Pubsub_Option,
+  Pubsub_Features, Xmlels) ->
+    case lists:member(<<"presence-notifications">>, Pubsub_Features) of
+        true  -> parse_xmlel_value('boolean', Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+%parse_pubsub_option_item(<<"publish_model">> = _Pubsub_Option,
+%  Pubsub_Features, Xmlels) ->
+%    case lists:member(<<"publish">>, Pubsub_Features) of
+%        true ->
+%            parse_xmlel_value({'list-single', 'atom',
+%                _Default_Values = ['open', 'publishers', 'subscribers']},
+%                Xmlels);
+%        false ->
+%            {error, 'invalid-options'}
+%    end;
+%%
+parse_pubsub_option_item(<<"purge_offline">> = _Pubsub_Option, Pubsub_Features,
+  Xmlels) ->
+    case lists:member(<<"purge-nodes">>, Pubsub_Features) of
+        true  -> parse_xmlel_value('boolean', Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_item(<<"roster_groups_allowed">> = _Pubsub_Option,
+  Pubsub_Features, [] = _Xmlels) ->
+    case lists:member(<<"access-roster">>, Pubsub_Features) of
+        true  -> {ok, []};
+        false -> {error, 'invalid-options'}
+    end;
+parse_pubsub_option_item(<<"roster_groups_allowed">> = _Pubsub_Option,
+  Pubsub_Features, Xmlels) ->
+    case lists:member(<<"access-roster">>, Pubsub_Features) of
+        true  -> parse_xmlel_value('list-multi', Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_item(<<"send_last_published_item">> = _Pubsub_Option,
+  Pubsub_Features, Xmlels) ->
+    case lists:member(<<"last-published">>, Pubsub_Features) of
+        true ->
+            parse_xmlel_value({'list-single', 'atom',
+                _Default_Values = case
+                    lists:member(<<"presence-notifications">>, Pubsub_Features)
+                of
+                    true  -> ['never', 'on_sub', 'on_sub_and_presence'];
+                    false -> ['never', 'on_sub']
+                end},
+                Xmlels);
+        false ->
+            {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_item(<<"type">> = _Pubsub_Option, Pubsub_Features,
+  [] = _Xmlels) ->
+    case lists:member(<<"publish">>, Pubsub_Features) of
+        true  -> {ok, undefined};
+        false -> {error, 'invalid-options'}
+    end;
+parse_pubsub_option_item(<<"type">> = _Pubsub_Option, Pubsub_Features, Xmlels) ->
+    case lists:member(<<"publish">>, Pubsub_Features) of
+        true  -> parse_xmlel_value({'text-single', 'atom'}, Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_item(_Pubsub_Option, _Pubsub_Features, _Xmlels) ->
+    {error, 'invalid-options'}.
+
+%%
+%%
+-spec(parse_pubsub_option_subscription/5 ::
+(
+  Pubsub_Option   :: binary(),
+  Node_Type       :: 'collection' | 'leaf',
+  Entity_Type     :: 'local' | 'remote',
+  Pubsub_Features :: exmpp_pubsub:pubsub_features(),
+  Xmlels          :: [Xmlel_Value::xmlel()]
+                   | [Xmlel::xmlel()])
+    ->
+   %   {ok, Digest             :: boolean()}
+   % | {ok, Digest_Frequency   :: undefined | non_neg_integer()}
+       {ok, Deliver            :: boolean()}
+     | {ok, Expire             :: undefined | 'presence' | erlang:timestamp()}
+%    | {ok, Include_Body       :: boolean()}
+     | {ok, Show_Values        :: ['away' | 'chat' | 'dnd' | 'online' | 'xa']}
+%    | {ok, Subscription_Type  :: 'all' | 'items' | 'nodes'}
+%    | {ok, Subscription_Depth :: 'all' | non_neg_integer()}
+    %%%
+     | {error, 'invalid-options'}
+     %
+     | {error, 'not-acceptable'}
+).
+
+%% parse_pubsub_option_subscription(<<"digest">> = _Pubsub_Option,
+%%  'leaf' = _Node_Type, _Entity_Type, Pubsub_Features, Xmlels) ->
+%%    case lists:member(<<"subscribe">>, Pubsub_Features) of
+%%       true ->
+%%            parse_xmlel_value('boolean', Xmlels);
+%%        false ->
+%%            {error, 'invalid-options'}
+%%    end;
+%%
+%% parse_pubsub_option_subscription(<<"digest_frequency">> = _Pubsub_Option,
+%%  'leaf' = _Node_Type, _Entity_Type, Pubsub_Features, Xmlels) ->
+%%    case lists:member(<<"subscribe">>, Pubsub_Features) of
+%%       true ->
+%%            parse_xmlel_value({'text-single', 'integer'}, Xmlels);
+%%        false ->
+%%            {error, 'invalid-options'}
+%%    end;
+%%
+parse_pubsub_option_subscription(<<"deliver">> = _Pubsub_Option, Node_Type,
+  _Entity_Type, Pubsub_Features, Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    case lists:member(<<"subscribe">>, Pubsub_Features) of
+        true  -> parse_xmlel_value('boolean', Xmlels);
+        false -> {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_subscription(<<"expire">> = _Pubsub_Option, Node_Type,
+  'local' = _Entity_Type, Pubsub_Features, [] = _Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    case
+        lists:member(<<"presence-notifications">>, Pubsub_Features)
+            orelse
+        lists:member(<<"leased-subscriptions">>, Pubsub_Features)
+    of
+        true  -> {ok, undefined};
+        false -> {error, 'invalid-options'}
+    end;
+parse_pubsub_option_subscription(<<"expire">> = _Pubsub_Option, Node_Type,
+  'local' = _Entity_Type, Pubsub_Features, [Xmlel_Value])
+  when    Node_Type == 'collection' orelse Node_Type == 'leaf'
+  andalso ?Is_Xmlel_Value(Xmlel_Value) ->
+    case {xmlns(Xmlel_Value), get_tag_cdata(Xmlel_Value)} of
+        {?NS_XDATA, <<>>} ->
+            {ok, undefined};
+        {?NS_XDATA, <<"presence">>} ->
+            case lists:member(<<"presence-notifications">>, Pubsub_Features) of
+                true  -> {ok, 'presence'};
+                false -> {error, 'invalid-options'}
+            end;
+        {?NS_XDATA, CData} ->
+            case lists:member(<<"leased-subscriptions">>, Pubsub_Features) of
+                true ->
+                    case jlib:datetime_string_to_timestamp(CData) of
+                        undefined -> {error, 'not-acceptable'};
+                        DateTime  -> {ok, DateTime}
+                    end;
+                false ->
+                    {error, 'invalid-options'}
+            end;
+        _ ->
+            {error, 'invalid-options'}
+    end;
+%
+parse_pubsub_option_subscription(<<"expire">> = _Pubsub_Option, Node_Type,
+  'remote' = _Entity_Type, Pubsub_Features, [] = _Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    case lists:member(<<"leased-subscriptions">>, Pubsub_Features) of
+        true  -> {ok, undefined};
+        false -> {error, 'invalid-options'}
+    end;
+parse_pubsub_option_subscription(<<"expire">> = _Pubsub_Option, Node_Type,
+  'remote' = _Entity_Type, Pubsub_Features, [Xmlel_Value])
+  when    Node_Type == 'collection' orelse Node_Type == 'leaf'
+  andalso ?Is_Xmlel_Value(Xmlel_Value) ->
+    case {xmlns(Xmlel_Value), get_tag_cdata(Xmlel_Value)} of
+        {?NS_XDATA, <<>>} ->
+            {ok, undefined};
+        {?NS_XDATA, <<"presence">>} ->
+            {error, 'invalid-options'};
+        {?NS_XDATA, CData} ->
+            case lists:member(<<"leased-subscriptions">>, Pubsub_Features) of
+                true ->
+                    case jlib:datetime_string_to_timestamp(CData) of
+                        undefined -> {error, 'not-acceptable'};
+                        DateTime  -> {ok, DateTime}
+                    end;
+                false ->
+                    {error, 'invalid-options'}
+            end;
+        _ ->
+            {error, 'invalid-options'}
+    end;
+%%
+%parse_pubsub_option_subscription(<<"include_body">> = _Pubsub_Option,
+%  'leaf' = _Node_Type, _Entity_Type, Pubsub_Features, Xmlels) ->
+%    case lists:member(<<"subscribe">>, Pubsub_Features) of
+%        true ->
+%            parse_xmlel_value('boolean', Xmlels);
+%        false ->
+%            {error, 'invalid-options'}
+%    end;
+%%
+parse_pubsub_option_subscription(<<"show-values">> = _Pubsub_Option, Node_Type,
+  'local' = _Entity_Type, Pubsub_Features, [] = _Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    case lists:member(<<"presence-notifications">>, Pubsub_Features) of
+        true  -> {ok, []};
+        false -> {error, 'invalid-options'}
+    end;
+parse_pubsub_option_subscription(<<"show-values">> = _Pubsub_Option, Node_Type,
+  'local' = _Entity_Type, Pubsub_Features, Xmlels)
+  when Node_Type == 'collection' orelse Node_Type == 'leaf' ->
+    case lists:member(<<"presence-notifications">>, Pubsub_Features) of
+        true ->
+            parse_xmlel_value({'list-multi', 'atom',
+                _Default_Values = ['away' ,'chat', 'dnd', 'online', 'xa']},
+                Xmlels);
+        false ->
+            {error, 'invalid-options'}
+    end;
+%%
+parse_pubsub_option_subscription(<<"show-values">> = _Pubsub_Option, _Node_Type,
+  'remote' = _Entity_Type, _Pubsub_Features, _Xmlels) ->
+    {error, 'invalid-options'};
+%%
+%parse_pubsub_option_subscription(<<"subscription_type">> = _Pubsub_Option,
+%  'collection' = _Node_Type, _Entity_Type, _Pubsub_Features, Xmlels) ->
+%    parse_xmlel_value({'list-single', 'atom',
+%        _Default_Values = ['all', 'items', 'nodes']}, Xmlels);
+%%
+%parse_pubsub_option_subscription(<<"subscription_depth">> = _Pubsub_Option,
+%  'collection' = _Node_Type, _Entity_Type, _Pubsub_Features, Xmlels) ->
+%    case Xmlels of
+%        [] ->
+%            {ok, 0};
+%        [Xmlel_Value] when ?Is_Xmlel_Value(Xmlel_Value) ->
+%            case {Xmlns(Xmlel_Value), get_tag_cdata(Xmlel_Value)} of
+%                {?NS_XDATA, <<>>} ->
+%                    {ok, 0};
+%                {?NS_XDATA, <<"all">>} ->
+%                    {ok, 'all'};
+%                {?NS_XDATA, CData} ->
+%                    case catch list_to_integer(binary_to_list(CData)) of
+%                        Integer
+%                          when is_integer(Integer) andalso Integer > -1 ->
+%                            {ok, Integer};
+%                        _Error ->
+%                            {error, 'not-acceptable'}
+%                    end;
+%                _ ->
+%                    {error, 'not-acceptable'}
+%            end;
+%        _Xmlels ->
+%            {error, 'not-acceptable'}
+%    end;
+%%
+parse_pubsub_option_subscription(_Pubsub_Option, _Node_Type, _Entity_Type,
+  _Pubsub_Features, _Xmlels) ->
+    {error, 'invalid-options'}.
+
+
+-spec(parse_xmlel_value/2 ::
+(
+  DataType     :: {'jid-multi',   'bare'}
+                | {'jid-multi',   'full'}
+                | {'list-multi', 'atom', Default_Values::[Default_Value::atom(),...]}
+                | 'list-multi'
+                | 'text-multi'
+                | {'access_model', Pubsub_Features::exmpp_pubsub:pubsub_features()}
+                | 'boolean'
+                | 'text-single'
+                | {'text-single', 'atom'}
+                | {'text-single', 'integer'}
+                | {'list-single', 'atom', Default_Values::[Default_Value::atom(),...]},
+  Xmlels       :: [Xmlel_Value::xmlel()]
+                | [Xmlel::xmlel()])
+    -> %%
+       {ok, Values :: []
+                    | [Value::binary()]
+                    | [Value::atom()]
+                    | [Value::xmpp_jid:raw_jid_entity_bare()]
+                    | [Value::xmpp_jid:raw_jid_entity()]}
+     | {ok, Value :: atom()
+                   | binary()
+                   | boolean()
+                   | non_neg_integer()
+                   | undefined}
+    %%%
+     | {error, 'invalid-options'}
+     | {error, 'jid-malformed'}
+     | {error, 'not-acceptable'}
+     | {error, 'not-acceptable', 'unsupported-access-model'}
+).
+
+%%
+parse_xmlel_value({'jid-multi', 'bare'}, [] = _Xmlels) ->
+    {ok, []};
+%%
+parse_xmlel_value({'jid-multi', 'bare'}, Xmlels) ->
+    parse_xmlel_value({'jid-multi', 'bare'}, Xmlels, []);
+%%
+parse_xmlel_value({'jid-multi', 'full'}, [] = _Xmlels) ->
+    {ok, []};
+%%
+parse_xmlel_value({'jid-multi', 'full'}, Xmlels) ->
+    parse_xmlel_value({'jid-multi', 'full'}, Xmlels, []);
+%%
+%%
+parse_xmlel_value({'list-multi', 'atom', _Default_Values}, [] = _Xmlels) ->
+    {error, 'not-acceptable'};
+%%
+parse_xmlel_value({'list-multi', 'atom', Default_Values}, Xmlels) ->
+    parse_xmlel_value({'list-multi', 'atom', Default_Values}, Xmlels, []);
+%%
+parse_xmlel_value('list-multi', Xmlels) ->
+    parse_xmlel_value('list-multi', Xmlels, []);
+%%
+%%
+parse_xmlel_value('text-multi', [] = _Xmlels) ->
+    {ok, []};
+%%
+parse_xmlel_value('text-multi', Xmlels) ->
+    parse_xmlel_value('text-multi', Xmlels, []);
+%%
+
+parse_xmlel_value({'access_model', Pubsub_Features}, [Xmlel_Value])
+  when ?Is_Xmlel_Value(Xmlel_Value) ->
+    case {xmlns(Xmlel_Value), get_tag_cdata(Xmlel_Value)} of
+        {?NS_XDATA, <<"authorize">>} ->
+            case lists:member(<<"access-authorize">>, Pubsub_Features) of
+                true  ->
+                    {ok, 'authorize'};
+                false ->
+                    {error, 'not-acceptable', 'unsupported-access-model'}
+            end;
+        %%
+        {?NS_XDATA, <<"open">>} ->
+            case lists:member(<<"access-open">>, Pubsub_Features) of
+                true  ->
+                    {ok, 'open'};
+                false ->
+                    {error, 'not-acceptable', 'unsupported-access-model'}
+            end;
+        %%
+        {?NS_XDATA, <<"presence">>} ->
+            case lists:member(<<"access-presence">>, Pubsub_Features) of
+                true  ->
+                    {ok, 'presence'};
+                false ->
+                    {error, 'not-acceptable', 'unsupported-access-model'}
+            end;
+        %%
+        {?NS_XDATA, <<"roster">>} ->
+            case lists:member(<<"access-roster">>, Pubsub_Features) of
+                true  ->
+                    {ok, 'roster'};
+                false ->
+                    {error, 'not-acceptable', 'unsupported-access-model'}
+            end;
+        %%
+        {?NS_XDATA, <<"whitelist">>} ->
+            case lists:member(<<"access-whitelist">>, Pubsub_Features) of
+                true  ->
+                    {ok, 'whitelist'};
+                false ->
+                    {error, 'not-acceptable', 'unsupported-access-model'}
+            end;
+        %%
+        _ ->
+            {error, 'not-acceptable'}
+    end;
+parse_xmlel_value({'access_model', _Pubsub_Features}, _Xmlels) ->
+    {error, 'not-acceptable'};
+%%
+%%
+parse_xmlel_value('boolean', [Xmlel_Value])
+  when ?Is_Xmlel_Value(Xmlel_Value) ->
+    case {xmlns(Xmlel_Value), get_tag_cdata(Xmlel_Value)} of
+        {?NS_XDATA, False}
+          when   False == <<"0">>
+          orelse False == <<"false">> -> 
+            {ok, false};
+        {?NS_XDATA, True}
+          when   True == <<"1">>
+          orelse True == <<"true">> -> 
+            {ok, true};
+        _ ->
+            {error, 'not-acceptable'}
+    end;
+parse_xmlel_value('boolean', _Xmlels) ->
+    {error, 'not-acceptable'};
+%%
+%%
+parse_xmlel_value('text-single', [] = _Xmlels) ->
+    {ok, undefined};
+parse_xmlel_value('text-single', [Xmlel_Value])
+  when ?Is_Xmlel_Value(Xmlel_Value) ->
+    case {xmlns(Xmlel_Value), get_tag_cdata(Xmlel_Value)} of
+        {?NS_XDATA, <<>>}  -> {ok, undefined};
+        {?NS_XDATA, CData} -> {ok, CData};
+        _                  -> {error, 'not-acceptable'}
+    end;
+parse_xmlel_value('text-single', _Xmlels) ->
+    {error, 'not-acceptable'};
+%%
+%%
+parse_xmlel_value({'text-single', 'atom'}, [] = _Xmlels) ->
+    {ok, undefined};
+parse_xmlel_value({'text-single', 'atom'}, [Xmlel_Value])
+  when ?Is_Xmlel_Value(Xmlel_Value) ->
+    case {xmlns(Xmlel_Value), get_tag_cdata(Xmlel_Value)} of
+        {?NS_XDATA, <<>>}  -> {ok, undefined};
+        {?NS_XDATA, CData} -> {ok, list_to_atom(binary_to_list(CData))};
+        _                  -> {error, 'not-acceptable'}
+    end;
+parse_xmlel_value({'text-single', 'atom'}, _Xmlels) ->
+    {error, 'not-acceptable'};
+%%
+%%
+parse_xmlel_value({'text-single', 'integer'}, [] = _Xmlels) ->
+    {ok, undefined};
+parse_xmlel_value({'text-single', 'integer'}, [Xmlel_Value])
+  when ?Is_Xmlel_Value(Xmlel_Value) ->
+    case {xmlns(Xmlel_Value), get_tag_cdata(Xmlel_Value)} of
+        {?NS_XDATA, <<>>}  ->
+            {ok, undefined};
+        {?NS_XDATA, CData} ->
+            case catch list_to_integer(binary_to_list(CData)) of
+                Integer when is_integer(Integer) andalso Integer > -1 ->
+                    {ok, Integer};
+                _ ->
+                    {error, 'not-acceptable'}
+            end;
+        _ ->
+            {error, 'not-acceptable'}
+    end;
+parse_xmlel_value({'text-single', 'integer'}, _Xmlels) ->
+    {error, 'not-acceptable'};
+%%
+%%
+parse_xmlel_value({'list-single', 'atom', Default_Values}, [Xmlel_Value])
+  when ?Is_Xmlel_Value(Xmlel_Value) ->
+    case {xmlns(Xmlel_Value), get_tag_cdata(Xmlel_Value)} of
+        {_, <<>>} ->
+            {error, 'not-acceptable'};
+        {?NS_XDATA, CData} ->
+            case
+                lists:member(Value = list_to_atom(binary_to_list(CData)),
+                    Default_Values)
+            of
+                true  ->
+                    {ok, Value};
+                false ->
+                    {error, 'not-acceptable'}
+            end;
+        _ ->
+            {error, 'not-acceptable'}
+    end;
+parse_xmlel_value({'list-single', 'atom', _Default_Values}, _Xmlels) ->
+    {error, 'not-acceptable'};
+%%
+parse_xmlel_value({_DataType, _Default_Values}, _Xmlels) ->
+    {error, 'not-acceptable'}.
+%%
+
+%%
+-spec(parse_xmlel_value/3 ::
+(
+  DataType :: {'list-multi', 'atom', Default_Values::[Default_Value::atom(),...]}
+            | 'list-multi'
+            | 'text-multi'
+            | {'jid-multi', 'full'}
+            | {'jid-multi', 'bare'},
+  Xmlels   :: [Xmlel_Value::xmlel()]
+            | [Xmlel::xmlel()],
+  Values   :: [Value::binary()]
+            | [Value::atom()]
+            | [Value::xmpp_jid:raw_jid_entity_bare()]
+            | [Value::xmpp_jid:raw_jid_entity_full()])
+    -> {ok,
+        Values :: [Value::binary()]
+                | [Value::atom()]
+                | [Value::xmpp_jid:raw_jid_entity_bare()]
+                | [Value::xmpp_jid:raw_jid_entity_full()]}
+    %%%
+     | {error, 'not-acceptable'}
+     | {error, 'jid-malformed'}
+).
+
+parse_xmlel_value(_DataType, _Xmlels = [], Values) ->
+    {ok, lists:usort(Values)};
+%%
+%%
+parse_xmlel_value({'list-multi', 'atom', Default_Values},
+  [Xmlel_Value | Xmlels], Values)
+  when ?Is_Xmlel_Value(Xmlel_Value) ->
+    case {xmlns(Xmlel_Value), get_tag_cdata(Xmlel_Value)} of
+        {?NS_XDATA, <<>>} ->
+            parse_xmlel_value({'list-multi', 'atom', Default_Values},
+                Xmlels, Values);
+        {?NS_XDATA, CData} ->
+            case
+                lists:member(Value = list_to_atom(binary_to_list(CData)),
+                    Default_Values)
+            of
+                true ->
+                    parse_xmlel_value({'list-multi', 'atom', Default_Values},
+                        Xmlels, [Value | Values]);
+                false ->
+                    {error, 'not-acceptable'}
+            end;
+        _ ->
+            {error, 'not-acceptable'}
+    end;
+%%
+%%
+parse_xmlel_value('list-multi', [Xmlel_Value | Xmlels], Values)
+  when ?Is_Xmlel_Value(Xmlel_Value) ->
+    parse_xmlel_value('list-multi', Xmlels,
+       case {xmlns(Xmlel_Value), get_tag_cdata(Xmlel_Value)} of
+           {?NS_XDATA, <<>>}  -> Values;
+           {?NS_XDATA, CData} -> [CData | Values];
+           _                  -> {error, 'not-acceptable'}
+       end);
+%%
+%%
+parse_xmlel_value('text-multi', [Xmlel_Value | Xmlels] , Values)
+  when ?Is_Xmlel_Value(Xmlel_Value) ->
+    parse_xmlel_value('text-multi', Xmlels,
+      case {xmlns(Xmlel_Value), get_tag_cdata(Xmlel_Value)} of
+          {?NS_XDATA, <<>>}  -> Values;
+          {?NS_XDATA, CData} -> [_Value = CData | Values];
+          _                  -> {error, 'not-acceptable'}
+      end);
+%%
+%%
+parse_xmlel_value({'jid-multi', 'full'}, [Xmlel_Value | Xmlels], Values)
+  when ?Is_Xmlel_Value(Xmlel_Value) ->
+    case {xmlns(Xmlel_Value), get_tag_cdata(Xmlel_Value)} of
+        {?NS_XDATA, <<>>} ->
+            parse_xmlel_value({'jid-multi', 'full'}, Xmlels, Values);
+        {?NS_XDATA, CData} ->
+            case is_jid(CData) of
+                #jid{} = Jid ->
+                    parse_xmlel_value({'jid-multi', 'full'}, Xmlels,
+                        [jlib:jid_to_string(Jid) | Values]);
+                Error ->
+                    Error
+            end;
+        _ ->
+            {error, 'not-acceptable'}
+    end;
+%%
+parse_xmlel_value({'jid-multi', 'bare'}, [Xmlel_Value | Xmlels], Values)
+  when ?Is_Xmlel_Value(Xmlel_Value) ->
+    case {xmlns(Xmlel_Value), get_tag_cdata(Xmlel_Value)} of
+        {?NS_XDATA, <<>>} ->
+            parse_xmlel_value({'jid-multi', 'bare'}, Xmlels, Values);
+        {?NS_XDATA, CData} ->
+            case is_jid(CData) of
+                #jid{} = Jid ->
+                    parse_xmlel_value({'jid-multi', 'bare'}, Xmlels,
+                        [jlib:jid_to_string(Jid#jid{resource = <<>>, lresource = <<>>})
+                        | Values]);
+                Error ->
+                    Error
+          end;
+        _ ->
+            {error, 'not-acceptable'}
+    end;
+%%
+parse_xmlel_value(_Data_Type, _Xmlels, _Values) ->
+    {error, 'not-acceptable'}.
+
+%%
+%%
+-spec(xdata_x/6 ::
+(
+  Options_Type    :: 'node_config' | 'subscribe_options',
+  Form_Type       :: 'form' | 'result',
+  Pubsub_Features :: exmpp_pubsub:pubsub_features(),
+  Host            :: xmpp_jid:raw_jid_component_bare(),
+  Entity          :: xmpp_jid:usr_bare(),
+  Options         :: pubsub_options:options_node()
+                   | pubsub_options:options_subscription())
+    -> Xmlel_X::xmlel()
+).
+
+xdata_x('node_config', 'form', Pubsub_Features, Host, Entity, Node_Options) ->
+    xmpp_xdata:xmlel_x(<<"form">>,
+        _Xmlels_Field = [
+            xmpp_xdata:xmlel_field(<<"FORM_TYPE">>, <<"hidden">>,
+                [?NS_PUBSUB_NODE_CONFIG])
+           |xdata_field(Pubsub_Features, Host, Entity, Node_Options, [])
+        ]);
+
+xdata_x('subscribe_options', 'form', Pubsub_Features, Host, Entity,
+  Subscription_Options) ->
+    xmpp_xdata:xmlel_x(<<"form">>,
+        _Xmlels_Field = [
+            xmpp_xdata:xmlel_field(<<"FORM_TYPE">>, <<"hidden">>,
+                [?NS_PUBSUB_SUBSCRIBE_OPTIONS])
+           |xdata_field(Pubsub_Features, Host, Entity, Subscription_Options, [])
+        ]);
+
+xdata_x('subscribe_options', 'result', Pubsub_Features, Host, Entity,
+  Subscription_Options) ->
+    xmpp_xdata:xmlel_x(<<"result">>,
+        _Xmlels_Field = [
+            xmpp_xdata:xmlel_field(<<"FORM_TYPE">>, <<"hidden">>,
+                [?NS_PUBSUB_SUBSCRIBE_OPTIONS])
+           |xdata_field(Pubsub_Features, Host, Entity, Subscription_Options, [])
+        ]).
+
+%%
+%%
+-spec(xdata_x/7 ::
+(
+  Options_Type                 :: 'subscribe_options',
+  Form_Type                    :: 'form',
+  Pubsub_Features              :: exmpp_pubsub:pubsub_features(),
+  Host                         :: xmpp_jid:raw_jid_component_bare(),
+  Entity                       :: xmpp_jid:usr_bare(),
+  Subscription_Options         :: [] | pubsub_options:options_subscription(),
+  Default_Subscription_Options :: pubsub_options:options_subscription())
+    -> Xmlel_X::xmlel()
+).
+
+
+%%
+xdata_x('subscribe_options', 'form', Pubsub_Features, Host, Entity,
+  Subscription_Options, Default_Subscription_Options) ->
+    xmpp_xdata:xmlel_x(<<"form">>,
+        _Xmlels_Field = [
+            xmpp_xdata:xmlel_field(<<"FORM_TYPE">>, <<"hidden">>,
+                [?NS_PUBSUB_SUBSCRIBE_OPTIONS])
+           |xdata_field(Pubsub_Features, Host, Entity,
+                filter_subscription_options(Subscription_Options,
+                    Default_Subscription_Options, []),
+                [])
+        ]).
+
+%%
+-spec(filter_subscription_options/3 ::
+(
+  Options                      :: [] | pubsub_options:options_subscription(),
+  Default_Subscription_Options :: pubsub_options:options_subscription(),
+  Subscription_Options         :: [] | pubsub_options:options_subscription())
+    -> Subscription_Options::pubsub_options:options_subscription()
+).
+
+filter_subscription_options([] = _Options, Default_Subscription_Options,
+  Subscription_Options) ->
+    Default_Subscription_Options ++ Subscription_Options;
+%%
+filter_subscription_options([{Key, Value} | Options], Default_Subscription_Options,
+  Subscription_Options) ->
+    filter_subscription_options(Options,
+        lists:keydelete(Key, 1, Default_Subscription_Options),
+        [{Key, Value} | Subscription_Options]).
+
+
+-define(Label_Deliver, <<"Enable delivery ?">>).
+-define(Label_Digest, <<"Receive digest notifications ?">>).
+-define(Label_Digest_Frequency, <<"Receive digest notifications (approx. one per day)?">>).
+-define(Label_Expire, <<"Requested lease period">>).
+-define(Label_Include_Body, <<"Receive message body in addition to payload ?">>).
+-define(Label_Show_Values, <<"Select the presence types which are allowed to receive event notifications">>).
+
+%%
+%% pubsub#subscribe_options
+%%
+-spec(xdata_field/5 ::
+(
+  Pubsub_Features :: exmpp_pubsub:pubsub_features(),
+  Host            :: xmpp_jid:raw_jid_component_bare(),
+  Entity          :: xmpp_jid:usr_bare(),
+  Options         :: [] | pubsub_options:options_subscription(),
+  Xmlels_Field    :: [] | [Xmlel_Field::xmlel(),...])
+    -> Xmlels_Field::[Xmlel_Field::xmlel(),...]
+).
+%%
+xdata_field(_Pubsub_Features, _Host, _Entity, [] = _Options, Xmlels_Field) ->
+    lists:sort(Xmlels_Field);
+%% 'pubsub#deliver'
+xdata_field(Pubsub_Features, Host, Entity, [{'deliver', Deliver} | Options],
+  Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_boolean(
+             <<"pubsub#deliver">>,
+             <<"Enable delivery?">>,
+             xdata_value('boolean', Deliver))
+        | Xmlels_Field]);
+%% 'pubsub#digest'
+xdata_field(Pubsub_Features, Host, Entity, [{'digest', Digest} | Options],
+  Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_boolean(
+             <<"pubsub#digest">>,
+             <<"Receive digest notifications (approx. one per day)?">>,
+             xdata_value('boolean', Digest))
+        | Xmlels_Field]);
+%% 'pubsub#digest_frequency'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'digest_frequency', Digest_Frequency} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_text_single(
+            <<"pubsub#digest_frequency">>,
+            <<"Receive digest notifications (approx. one per day)?">>,
+            xdata_value('integer', Digest_Frequency))
+        | Xmlels_Field]);
+%% 'pubsub#expire'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'expire', Expire} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_text_single(
+            <<"pubsub#expire">>,
+            <<"Requested lease period">>,
+            case is_atom(Expire) of
+                true  -> xdata_value('atom', Expire);
+                false -> xdata_value('date', Expire)
+            end)
+        | Xmlels_Field]);
+%% 'pubsub#include_body'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'include_body', Include_Body} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_boolean(
+             <<"pubsub#include_body">>,
+             <<"Receive message body in addition to payload?">>,
+             xdata_value('boolean', Include_Body))
+        | Xmlels_Field]);
+%% 'pubsub#show-values'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'show-values', Show_Values} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_list_multi(
+            <<"pubsub#show-values">>,
+            <<"Select the presence types which are allowed to receive event notifications">>,
+            lists:map(fun
+                ('away')   -> <<"away">>;
+                ('chat')   -> <<"chat">>;
+                ('dnd')    -> <<"dnd">>;
+                ('online') -> <<"online">>;
+                ('xa')     -> <<"xa">>
+            end, Show_Values),
+            [{<<"away">>,   <<"Away">>},
+             {<<"chat">>,   <<"Want to Chat">>},
+             {<<"dnd">>,    <<"Do Not Disturb">>},
+             {<<"online">>, <<"Available">>},
+             {<<"xa">>,     <<"Extended Away">>}])
+        | Xmlels_Field]);
+%% 'pubsub#subscription_type'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'subscription_type', Subscription_Type} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_list_single(
+            <<"pubsub#subscription_type">>,
+            <<"Subscription Type">>,
+            case Subscription_Type of
+                undefined -> <<"items">>;
+                'items'   -> <<"items">>;
+                'nodes'   -> <<"nodes">>;
+                'all'     -> <<"all">>
+            end,
+            [{<<"items">>, <<"Receive notification of items only">>},
+             {<<"nodes">>, <<"Receive notification of new nodes only">>},
+             {<<"all">>,   <<"Receive notification of items and nodes">>}])
+        | Xmlels_Field]);
+%% 'pubsub#subscription_depth'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'subscription_depth', Subscription_Depth} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_list_single(
+            <<"pubsub#subscription_depth">>,
+            <<"How far to traverse the node graph for notifications">>,
+            case Subscription_Depth of
+                undefined -> <<"1">>;
+                'all'     -> <<"all">>;
+                _         -> xdata_value('integer', Subscription_Depth)
+
+            end,
+            [{<<"1">>,   <<"Receive notification from direct child nodes only">>},
+             {<<"all">>, <<"Receive notification from all descendent nodes">>}])
+        | Xmlels_Field]);
+%%
+%% pubsub#node_config
+%%
+%% 'pubsub#access_model'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'access_model', Access_Model} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_list_single(
+            <<"pubsub#access_model">>,
+            <<"Specify the subscriber model">>,
+            case Access_Model of
+               % undefined  -> <<"open">>;
+                'authorize' -> <<"authorize">>;
+                'open'      -> <<"open">>;
+                'presence'  -> <<"presence">>;
+                'roster'    -> <<"roster">>;
+                'whitelist' -> <<"whitelist">>
+            end,
+            xdata_access_model(Pubsub_Features,
+                ['authorize', 'open', 'presence', 'roster', 'whitelist']))
+        | Xmlels_Field]);
+%% 'pubsub#body_xslt'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'body_xslt', Xslt} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_text_single(
+            <<"pubsub#body_xslt">>,
+            <<"The URL of an XSL transformation which can be applied to "
+              "payloads in order to generate an appropriate message body element">>,
+            Xslt)
+        | Xmlels_Field]);
+%% 'pubsub#children_association_policy'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'children_association_policy', Children_Association_Policy} | Options],
+  Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_list_single(
+            <<"pubsub#children_association_policy">>,
+            <<"Who may associate leaf nodes with a collection">>,
+            case Children_Association_Policy of
+                undefined   -> <<"owners">>;
+                'owners'    -> <<"owners">>;
+                'all'       -> <<"all">>;
+                'whitelist' -> <<"whitelist">>
+            end,
+            [{<<"all">>,       <<"Anyone may associate leaf nodes with the collection">>},
+             {<<"owners">>,    <<"Only collection node owners may associate leaf"
+                                 " nodes with the collection">>},
+             {<<"whitelist">>, <<"Only those on a whitelist may associate leaf "
+                                 "nodes with the collection">>}])
+        | Xmlels_Field]);
+%% 'pubsub#children_association_whitelist'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'children_association_whitelist', Children_Association_Whitelist}
+  | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_jid_multi(
+             <<"pubsub#children_association_whitelist">>,
+             <<"The list of JIDs that may associate leaf nodes with a collection">>,
+             Children_Association_Whitelist)
+        | Xmlels_Field]);
+%% 'pubsub#children'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'children', Children} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_text_multi(
+             <<"pubsub#children">>,
+             <<"The child nodes (leaf or collection) associated with a collection">>,
+             Children)
+        | Xmlels_Field]);
+%% 'pubsub#children_max'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'children_max', Children_Max} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_text_single(
+            <<"pubsub#children_max">>,
+            <<"The maximum number of child nodes that can be associated with a collection">>,
+            xdata_value('integer', Children_Max))
+        | Xmlels_Field]);
+%% 'pubsub#collection'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'collection', Collection} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_text_multi(
+             <<"pubsub#collection">>,
+             <<"The collection(s) with which a node is affiliated">>,
+             Collection)
+        | Xmlels_Field]);
+%% 'pubsub#contact'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'contact', Contacts} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_jid_multi(
+             <<"pubsub#contact">>,
+             <<"The JIDs of those to contact with questions">>,
+             Contacts)
+        | Xmlels_Field]);
+%% 'pubsub#dataform_xslt'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'dataform_xslt', Dataform_Xslt} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_text_single(
+            <<"pubsub#dataform_xslt">>,
+            <<"Payload XSLT">>,
+            xdata_value({'text-multi', 'atom'}, Dataform_Xslt))
+        | Xmlels_Field]);
+%% 'pubsub#deliver_notifications'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'deliver_notifications', Deliver_Notifications} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_boolean(
+             <<"pubsub#deliver_notifications">>,
+             <<"Whether to deliver event notifications">>,
+             xdata_value('boolean', Deliver_Notifications))
+        | Xmlels_Field]);
+%% 'pubsub#deliver_payloads'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'deliver_payloads', Deliver_Payloads} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_boolean(
+             <<"pubsub#deliver_payloads">>,
+             <<"Whether to deliver payloads with event notifications">>,
+             xdata_value('boolean', Deliver_Payloads))
+        | Xmlels_Field]);
+%% 'pubsub#description'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'description', Description} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_text_single(
+            <<"pubsub#description">>,
+            <<"A description of the node">>,
+            Description)
+        | Xmlels_Field]);
+%% 'pubsub#item_expire'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'item_expire', Item_Expire} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_text_single(
+            <<"pubsub#item_expire">>,
+            <<"Number of seconds after which to automatically purge items">>,
+            xdata_value('integer', Item_Expire))
+        | Xmlels_Field]);
+%% 'pubsub#itemreply'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'itemreply', ItemReply} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_list_single(
+            <<"pubsub#itemreply">>,
+            <<"Whether owners or publisher should receive replies to items">>,
+            case ItemReply of
+                undefined   -> <<"publisher">>;
+                'owner'     -> <<"owner">>;
+                'publisher' -> <<"publisher">>
+            end,
+            [{<<"owner">>, <<"Statically specify a replyto of the node owner(s)">>},
+             {<<"publisher">>, <<"Dynamically specify a replyto of the item publisher">>}])
+        | Xmlels_Field]);
+%% 'pubsub#language'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'language', Language} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_list_single(
+            <<"pubsub#language">>,
+            <<"The default language of the node">>,
+            case Language of
+                undefined -> <<"en">>;
+                _Language  -> Language
+            end,
+            [{<<"en">>, <<"English">>}
+             %{<<"es">>, <<"Español">>},
+             %{<<"fr">>, <<"Français">>},
+             %{<<"pl">>, <<"Polski">>},
+             %{<<"ru">>, <<"Русский">>}
+             ])
+        | Xmlels_Field]);
+%% 'pubsub#max_items'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'max_items', Max_Items} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_text_single(
+            <<"pubsub#max_items">>,
+            <<"The maximum number of items to persist">>,
+            xdata_value('integer', Max_Items))
+        | Xmlels_Field]);
+%% 'pubsub#max_payload_size'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'max_payload_size', Max_Payload_Size} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_text_single(
+            <<"pubsub#max_payload_size">>,
+            <<"The maximum payload size in bytes">>,
+            xdata_value('integer', Max_Payload_Size))
+        | Xmlels_Field]);
+%% 'pubsub#node_type'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'node_type', Node_Type} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host,
+        Entity, Options,
+        [case lists:member(<<"collections">>, Pubsub_Features) of
+             true ->
+                 xmpp_xdata:xmlel_field_list_single(
+                     <<"pubsub#node_type">>,
+                     <<"Whether the node is a leaf (default) or a collection">>,
+                     case Node_Type of
+                         undefined    -> <<"leaf">>;
+                         'leaf'       -> <<"leaf">>;
+                         'collection' -> <<"collection">>
+                     end,
+                     [{<<"leaf">>, <<"The node is a leaf node (default)">>},
+                      {<<"collection">>, <<"The node is a collection node">>}]);
+             false ->
+                 %% Collections not supported -> non-modifiable field
+%                 xmpp_xdata:xmlel_field_fixed(
+%                     <<"pubsub#node_type">>,
+%                     <<"The node is a leaf node (default)">>,
+%                     <<"leaf">>)
+                 xmpp_xdata:xmlel_field_list_single(
+                     <<"pubsub#node_type">>,
+                     <<"Whether the node is a leaf (default) or a collection">>,
+                     <<"leaf">>,
+                     [{<<"leaf">>, <<"The node is a leaf node (default)">>}])
+         end
+        |Xmlels_Field]);
+%% 'pubsub#notification_type'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'notification_type', Notification_Type} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_list_single(
+            <<"pubsub#notification_type">>,
+            <<"Specify the delivery style for event notifications">>,
+            case Notification_Type of
+                undefined  -> <<"headline">>;
+                'headline' -> <<"headline">>;
+                'normal'   -> <<"normal">>;
+                'chat'     -> <<"chat">>
+            end,
+            [{<<"headline">>, <<"Messages of type headline">>},
+             {<<"normal">>,   <<"Messages of type normal">>}
+            %{<<"chat">>,     <<"Messages of type chat">>}
+            %{<<"presence">>, <<"Presence">>}
+            %{<<"iq">>,       <<"Iq">>}
+             ])
+        | Xmlels_Field]);
+%% 'pubsub#notify_config'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'notify_config', Notify_Config} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_boolean(
+             <<"pubsub#notify_config">>,
+             <<"Notify owners and subscribers when the node configuration changes">>,
+             xdata_value('boolean', Notify_Config))
+        | Xmlels_Field]);
+%% 'pubsub#notify_delete'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'notify_delete', Notify_Delete} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_boolean(
+             <<"pubsub#notify_delete">>,
+             <<"Notify owners and subscribers when the node is deleted">>,
+             xdata_value('boolean', Notify_Delete))
+        | Xmlels_Field]);
+%% 'pubsub#notify_retract'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'notify_retract', Notify_Retract} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_boolean(
+             <<"pubsub#notify_retract">>,
+             <<"Notify subscribers when items are removed from the node">>,
+             xdata_value('boolean', Notify_Retract))
+        | Xmlels_Field]);
+%% 'pubsub#notify_sub'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'notify_sub', Notify_Sub} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_boolean(
+             <<"pubsub#notify_sub">>,
+             <<"Notify owners about new subscribers and unsubscribes">>,
+             xdata_value('boolean', Notify_Sub))
+        | Xmlels_Field]);
+%% 'pubsub#persist_items'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'persist_items', Persist_Items} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_boolean(
+             <<"pubsub#persist_items">>,
+             <<"Persist items to storage">>,
+             xdata_value('boolean', Persist_Items))
+        | Xmlels_Field]);
+%% 'pubsub#presence_based_delivery'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'presence_based_delivery', Presence_Based_Delivery} | Options]
+ , Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_boolean(
+             <<"pubsub#presence_based_delivery">>,
+             <<"Deliver event notifications only to available users">>,
+             xdata_value('boolean', Presence_Based_Delivery))
+        | Xmlels_Field]);
+%% 'pubsub#publish_model'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'publish_model', Publish_Model} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_list_single(
+            <<"pubsub#publish_model">>,
+            <<"Specify the publisher model">>,
+            case Publish_Model of
+               % undefined    -> <<"open">>;
+                'open'        -> <<"open">>;
+                'publishers'  -> <<"publishers">>;
+                'subscribers' -> <<"subscribers">>
+            end,
+            [{<<"publishers">>,  <<"Only publishers may publish">>},
+             {<<"subscribers">>, <<"Subscribers may publish">>},
+             {<<"open">>,        <<"Anyone may publish">>}])
+        | Xmlels_Field]);
+%% 'pubsub#purge_offline'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'purge_offline', Purge_Offline} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_boolean(
+             <<"pubsub#purge_offline">>,
+             <<"Purge all items when the relevant publisher goes offline ?">>,
+             xdata_value('boolean', Purge_Offline))
+        | Xmlels_Field]);
+%% 'pubsub#roster_groups_allowed'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'roster_groups_allowed', Rosters_Groups_Allowed} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_list_multi(
+             <<"pubsub#roster_groups_allowed">>,
+             <<"Roster group(s) allowed to subscribe and retrieve items">>,
+             case lists:keyfind(Entity, 1, Rosters_Groups_Allowed) of
+                 false                    -> [];
+                 {_Entity, Roster_Groups} -> Roster_Groups
+             end,
+             xdata_roster(Host, Entity))
+        | Xmlels_Field]);
+%% 'pubsub#send_last_published_item'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'send_last_published_item', Send_Last_Published_Item} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_list_single(
+            <<"pubsub#send_last_published_item">>,
+            <<"When to send the last published item">>,
+            case Send_Last_Published_Item of
+                undefined             -> <<"on_sub_and_presence">>;
+                'never'               -> <<"never">>;
+                'on_sub_and_presence' -> <<"on_sub_and_presence">>;
+                'on_sub'              -> <<"on_sub">>
+            end,
+            [{<<"never">>,               <<"Never">>},
+             {<<"on_sub">>,              <<"When a new subscription is processed">>},
+             {<<"on_sub_and_presence">>, <<"When a new subscription is processed "
+                                           "and whenever a subscriber comes online">>}])
+        | Xmlels_Field]);
+%% 'pubsub#subscribe'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'subscribe', Subscribe} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_boolean(
+             <<"pubsub#subscribe">>,
+             <<"Whether to allow subscriptions">>,
+             xdata_value('boolean', Subscribe))
+        | Xmlels_Field]);
+%% 'pubsub#tempsub'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'tempsub', Tempsub} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_boolean(
+             <<"pubsub#tempsub">>,
+             <<"Make all subscriptions temporary, based on subscriber presence">>,
+             xdata_value('boolean', Tempsub))
+        | Xmlels_Field]);
+%% 'pubsub#title'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'title', Title} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_text_single(
+            <<"pubsub#title">>,
+            <<"A friendly name for the node">>,
+            Title)
+        | Xmlels_Field]);
+%% 'pubsub#type'
+xdata_field(Pubsub_Features, Host, Entity,
+  [{'type', Type} | Options], Xmlels_Field) ->
+    xdata_field(Pubsub_Features, Host, Entity, Options,
+        [xmpp_xdata:xmlel_field_text_single(
+             <<"pubsub#type">>,
+             <<"Specify the type of payload data to be provided at this node">>,
+             Type)
+        | Xmlels_Field]).
+
+
+
+%%
+-spec(xdata_value/2 ::
+(
+  DataType :: 'atom'
+            | 'boolean'
+            | 'date'
+            | 'integer'
+            | {'text-multi', 'atom'},
+  Value    :: undefined
+            | atom()
+            | boolean()
+            | erlang:timestamp()
+            | non_neg_integer()
+            | [atom()])
+    -> Xdata_Value :: binary() | [binary(),...]
+).
+
+xdata_value(_, undefined)     -> undefined;
+%%
+xdata_value('atom', Value)    -> list_to_binary(atom_to_list(Value));
+%%
+xdata_value('boolean', false) -> <<"false">>;
+xdata_value('boolean', true)  -> <<"true">>;
+%%
+xdata_value('date', TimeStamp) ->
+    {DateTime, _} = jlib:timestamp_to_iso(calendar:now_to_datetime(TimeStamp), utc),
+    list_to_binary(DateTime ++ "Z");
+%%
+xdata_value('integer', Value) -> list_to_binary(integer_to_list(Value));
+%%
+xdata_value({'text-multi', 'atom'}, Values) ->
+    [list_to_binary(atom_to_list(Value)) || Value <- Values].
+
+%%
+-spec(xdata_access_model/3 ::
+(
+  Access_Model   :: pubsub_options:access_model(),
+  Pubsub_Feature :: boolean(),
+  Access_Models  :: [{binary(), binary()}])
+    -> Access_Models :: [{binary(), binary()}]
+).
+
+xdata_access_model(_Access_Model, false, Access_Models) ->
+    Access_Models;
+%%
+xdata_access_model('authorize' = _Access_Model, true, Access_Models) ->
+    [{<<"authorize">>, <<"Subscription requests must be approved and only "
+                         "subscribers may retrieve items">>}
+    | Access_Models];
+%%
+xdata_access_model('open' = _Access_Model, true, Access_Models) ->
+    [{<<"open">>, <<"Anyone may subscribe and retrieve items">>}
+    | Access_Models];
+%%
+xdata_access_model('presence' = _Access_Model, true, Access_Models) ->
+    [{<<"presence">>, <<"Anyone with a presence subscription of both or from may "
+                        "subscribe and retrieve items">>}
+    | Access_Models];
+%%
+xdata_access_model('roster' = _Access_Model, true, Access_Models) ->
+    [{<<"roster">>, <<"Anyone in the specified roster group(s) may subscribe and "
+                      "retrieve items">>}
+    | Access_Models];
+%%
+xdata_access_model('whitelist' = _Access_Model, true, Access_Models) ->
+    [{<<"whitelist">>, <<"Only those on a whitelist may subscribe and retrieve items">>}
+    | Access_Models].
+
+%%
+-spec(xdata_access_model/2 ::
+(
+  Pubsub_Features      :: exmpp_pubsub:pubsub_features(),
+  Default_Access_Model :: ['authorize'|'open'|'presence'|'roster'|'whitelist',...])
+    -> Access_Models :: [{binary(), binary()},...]
+).
+
+xdata_access_model(Pubsub_Features, Default_Access_Models) ->
+    lists:foldr(fun
+        ('authorize', Access_Models) ->
+            xdata_access_model('authorize',
+                lists:member(<<"access-authorize">>, Pubsub_Features), Access_Models);
+        %%
+        ('open', Access_Models) ->
+            xdata_access_model('open',
+                lists:member(<<"access-open">>, Pubsub_Features), Access_Models);
+        %%
+        ('presence', Access_Models) ->
+            xdata_access_model('presence',
+                lists:member(<<"access-presence">>, Pubsub_Features), Access_Models);
+        %%
+        ('roster', Access_Models) ->
+            xdata_access_model('roster',
+                lists:member(<<"access-roster">>, Pubsub_Features), Access_Models);
+        %%
+        ('whitelist', Access_Models) ->
+            xdata_access_model('whitelist',
+                lists:member(<<"access-whitelist">>, Pubsub_Features), Access_Models)
+        %
+    end, [], Default_Access_Models).
+
+%%
+
+%% Local Entity
+-spec(xdata_roster/2 ::
+(
+  Host   :: binary(),
+  Entity :: xmpp_jid:usr_bare())
+    -> Roster_Groups :: [Roster_Group::binary()]
+).
+
+xdata_roster(Host, {_, Host, _} = Entity) ->
+    _Roster_Groups = lists:usort(lists:foldl(fun
+        (#roster{groups = Groups}, Roster_Groups) ->
+            lists:foldl(fun
+                (Group, Roster_Groups_Bis) ->
+                    [Group | Roster_Groups_Bis]
+                end, Roster_Groups, Groups)
+        end, [], _Roster = get_entity_roster(Entity)));
+%% Remote Entity
+xdata_roster(_Host, _Entity) ->
+    [].
diff --git a/src/mod_pubsub_ng/pubsub_parser.erl b/src/mod_pubsub_ng/pubsub_parser.erl
new file mode 100644
index 000000000..9bc7de36d
--- /dev/null
+++ b/src/mod_pubsub_ng/pubsub_parser.erl
@@ -0,0 +1,1442 @@
+%%% ====================================================================
+%%% ``The contents of this file are subject to the Erlang Public License,
+%%% Version 1.1, (the "License"); you may not use this file except in
+%%% compliance with the License. You should have received a copy of the
+%%% Erlang Public License along with this software. If not, it can be
+%%% retrieved via the world wide web at http://www.erlang.org/.
+%%% 
+%%% Software distributed under the License is distributed on an "AS IS"
+%%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%%% the License for the specific language governing rights and limitations
+%%% under the License.
+%%% 
+%%% The Initial Developer of the Original Code is ProcessOne.
+%%% Portions created by ProcessOne are Copyright 2006-2011, ProcessOne
+%%% All Rights Reserved.''
+%%% This software is copyright 2006-2011, ProcessOne.
+%%%
+%%% @copyright 2006-2011 ProcessOne
+%%% @author Karim Gemayel <karim.gemayel@process-one.net>
+%%%   [http://www.process-one.net/]
+%%% @version {@vsn}, {@date} {@time}
+%%% @end
+%%% ====================================================================
+
+%%% @headerfile "pubsub_dev.hrl"
+
+-module(pubsub_parser).
+-author('karim.gemayel@process-one.net').
+
+-compile({no_auto_import,[node/1]}).
+
+-compile(export_all).
+
+-include("pubsub_dev.hrl").
+-include("pubsub_api.hrl").
+
+-import(xml,
+[
+  get_tag_attr_s/2,
+  get_attr_s/2,
+  remove_cdata/1
+]).
+
+
+%-type('xmlel_affiliations#'() ::
+%  #xmlel{ns::?NS_PUBSUB, name::'affiliations', children::[]}
+%).
+
+%-type('xmlel_affiliations#owner'() ::
+%  #xmlel{ns::?NS_PUBSUB_OWNER, name::'affiliations', children::[]}
+%).
+
+%-type('xmlel_configure#'() ::
+%  #xmlel{ns::?NS_PUBSUB, name::'configure'}
+%).
+
+%-type('xmlel_configure#owner'() ::
+%  #xmlel{ns::?NS_PUBSUB_OWNER, name::'configure', children::[]}
+%).
+
+%-type('xmlel_create#'() ::
+%  #xmlel{ns::?NS_PUBSUB, name::'create', children::[]}
+%).
+
+%-type('xmlel_default#'() ::
+%  #xmlel{ns::?NS_PUBSUB, name::'default'}
+%).
+
+%-type('xmlel_default#owner'() ::
+%%  #xmlel{ns::?NS_PUBSUB_OWNER, name::'default', attrs::[], children::[]}
+%  #xmlel{ns::?NS_PUBSUB_OWNER, name::'default', children::[]}
+%).
+
+%-type('xmlel_delete#owner'() ::
+%  #xmlel{ns::?NS_PUBSUB_OWNER, name::'delete'}
+%).
+
+%-type('xmlel_items#'() ::
+%  #xmlel{ns::?NS_PUBSUB, name::'items'}
+%).
+
+%-type('xmlel_options1#'() ::
+%  #xmlel{ns::?NS_PUBSUB, name::'options', attrs::[]}
+%).
+
+%-type('xmlel_options2#'() ::
+%  #xmlel{ns::?NS_PUBSUB, name::'options'}
+%).
+
+%-type('xmlel_publish#'() ::
+%  #xmlel{ns::?NS_PUBSUB, name::'publish'}
+%).
+
+%-type('xmlel_publish-options#'() ::
+%  #xmlel{ns::?NS_PUBSUB, name::'publish-options'}
+%).
+
+%-type('xmlel_purge#owner'() ::
+%  #xmlel{ns::?NS_PUBSUB_OWNER, name::'purge', children::[]}
+%).
+
+%-type('xmlel_retract#'() ::
+%  #xmlel{ns::?NS_PUBSUB, name::'retract'}
+%).
+
+%-type('xmlel_subscribe#'() ::
+%  #xmlel{ns::?NS_PUBSUB, name::'subscribe', children::[]}
+%).
+
+%-type('xmlel_subscriptions#'() ::
+%  #xmlel{ns::?NS_PUBSUB, name::'subscriptions', children::[]}
+%).
+
+%-type('xmlel_subscriptions#owner'() ::
+%  #xmlel{ns::?NS_PUBSUB_OWNER, name::'subscriptions', children::[]}
+%).
+
+%-type('xmlel_unsubscribe#'() ::
+%  #xmlel{ns::?NS_PUBSUB, name::'unsubscribe', children::[]}
+%).
+
+
+-define(Is_Xmlel_Affiliations(Xmlel),
+(
+  Xmlel#xmlel.name     == <<"affiliations">>    andalso
+  Xmlel#xmlel.children == []
+)).
+
+-define(Is_Xmlel_Configure(Xmlel),
+(
+  Xmlel#xmlel.name     == <<"configure">>       andalso
+  Xmlel#xmlel.attrs    == []
+)).
+
+-define(Is_Xmlel_Create(Xmlel),
+(
+  Xmlel#xmlel.name     == <<"create">>          andalso
+  Xmlel#xmlel.children == []
+)).
+
+-define(Is_Xmlel_Default(Xmlel),
+(
+  %Xmlel#xmlel.ns       == ?NS_PUBSUB        andalso
+  Xmlel#xmlel.name     == <<"default">>         andalso
+  Xmlel#xmlel.children == []
+)).
+
+-define(Is_Xmlel_Delete(Xmlel),
+(
+  %Xmlel#xmlel.ns       == ?NS_PUBSUB_OWNER  andalso
+  Xmlel#xmlel.name     == <<"delete">>
+)).
+
+-define(Is_Xmlel_Item(Xmlel),
+(
+  %Xmlel#xmlel.ns       == ?NS_PUBSUB        andalso
+  Xmlel#xmlel.name     == <<"item">>            andalso
+  Xmlel#xmlel.children == []
+)).
+
+-define(Is_Xmlel_Items1(Xmlel),
+(
+  %Xmlel#xmlel.ns       == ?NS_PUBSUB        andalso
+  Xmlel#xmlel.name     == <<"items">>           andalso
+  Xmlel#xmlel.children == []
+)).
+
+-define(Is_Xmlel_Items2(Xmlel),
+(
+%Xmlel#xmlel.ns       == ?NS_PUBSUB        andalso
+  Xmlel#xmlel.name     == <<"items">>
+)).
+
+-define(Is_Xmlel_Options1(Xmlel),
+(
+%Xmlel#xmlel.ns       == ?NS_PUBSUB        andalso
+  Xmlel#xmlel.name     == <<"options">>         andalso
+  Xmlel#xmlel.attrs    == []
+)).
+
+-define(Is_Xmlel_Options2(Xmlel),
+(
+  %Xmlel#xmlel.ns       == ?NS_PUBSUB        andalso
+  Xmlel#xmlel.name     == <<"options">>
+)).
+
+-define(Is_Xmlel_Publish(Xmlel),
+(
+  %Xmlel#xmlel.ns       == ?NS_PUBSUB        andalso
+  Xmlel#xmlel.name     == <<"publish">>
+)).
+
+-define(Is_Xmlel_Publish_Options(Xmlel),
+(
+  %Xmlel#xmlel.ns       == ?NS_PUBSUB        andalso
+  Xmlel#xmlel.name     == <<"publish-options">> andalso
+  Xmlel#xmlel.attrs    == []
+)).
+
+-define(Is_Xmlel_Purge(Xmlel),
+(
+  %Xmlel#xmlel.ns       == ?NS_PUBSUB_OWNER  andalso
+  Xmlel#xmlel.name     == <<"purge">>           andalso
+  Xmlel#xmlel.children == []
+)).
+
+-define(Is_Xmlel_Redirect(Xmlel),
+(
+  %Xmlel#xmlel.ns       == ?NS_PUBSUB_OWNER  andalso
+  Xmlel#xmlel.name     == <<"redirect">>        andalso
+  Xmlel#xmlel.children == []
+)).
+
+-define(Is_Xmlel_Retract(Xmlel),
+(
+  %Xmlel#xmlel.ns       == ?NS_PUBSUB        andalso
+  Xmlel#xmlel.name     == <<"retract">>         andalso
+  Xmlel#xmlel.children =/= []
+)).
+
+-define(Is_Xmlel_Subscribe(Xmlel),
+(
+  %Xmlel#xmlel.ns       == ?NS_PUBSUB        andalso
+  Xmlel#xmlel.name     == <<"subscribe">>       andalso
+  Xmlel#xmlel.children == []
+)).
+
+-define(Is_Xmlel_Subscriptions(Xmlel),
+(
+  %Xmlel#xmlel.ns       == ?NS_PUBSUB        andalso
+  Xmlel#xmlel.name     == <<"subscriptions">>   andalso
+  Xmlel#xmlel.children == []
+)).
+
+-define(Is_Xmlel_Unsubscribe(Xmlel),
+(
+%Xmlel#xmlel.ns       == ?NS_PUBSUB        andalso
+  Xmlel#xmlel.name     == <<"unsubscribe">>     andalso
+  Xmlel#xmlel.children == []
+)).
+
+
+%%
+-spec(parse/4 ::
+(
+  IQ_Type  :: 'get' | 'set',
+  Xmlels   :: %-- Create_Node --%
+%              ['xmlel_create#'(),...]             |
+%           %%
+%              ['xmlel_create#'()
+%              |'xmlel_configure#'(),...]          |
+%           %% %-- Delete_Node --%
+%              ['xmlel_delete#owner'(),...]        |
+%           %% %-- Purge_Node --%
+%              ['xmlel_purge#owner'(),...]         |
+%           %% %-- Publish_Item --%
+%              ['xmlel_publish#'(),...]            |
+%           %%
+%              ['xmlel_publish#'()
+%              |'xmlel_configure#'(),...]          |
+%           %%
+%              ['xmlel_publish#'()
+%              |'xmlel_publish-options#'(),...]    |
+%           %%
+%              ['xmlel_publish#'()
+%              |'xmlel_configure#'()
+%              |'xmlel_publish-options#'(),...]    |
+%           %% %-- Retract_Item --%
+%              ['xmlel_retract#'(),...]            |
+%           %% %-- Subscribe_Node --%
+%              ['xmlel_subscribe#'(),...]          |
+%              ['xmlel_subscribe#'()
+%              |'xmlel_options1#'(),...]           |
+%           %% %-- Unsubscribe_Node --%
+%              ['xmlel_unsubscribe#'(),...]        |
+%           %% %-- Set_Configure_Subscription --%
+%              ['xmlel_options2#'(),...]           |
+%           %% %-- Get_Items --%
+%              ['xmlel_items#'(),...]              |
+%           %% %-- Get_Entity_Affiliations --%
+%              ['xmlel_affiliations#'(),...]       |
+%           %% %-- Get_Entity_Subscriptions --%
+%              ['xmlel_subscriptions#'(),...]      |
+%           %% %-- Get_Node_Affiliations --%
+%              ['xmlel_affiliations#owner'(),...]  |
+%           %% %-- Get_Node_Subscriptions --%
+%              ['xmlel_subscriptions#owner'(),...] |
+%           %% %-- Get_Configure_Subscription_Default --%
+%              ['xmlel_default#'(),...]            |
+%           %% %-- Get_Configure_Subscription --%
+%              ['xmlel_options2#'(),...]           |
+%           %% %-- Get_Configure_Node_Default --%
+%              ['xmlel_default#owner'(),...]       |
+%           %% %-- Get_Configure_Node --%
+%              ['xmlel_configure#owner'(),...]     |
+           %% %-- Other Stanza --%
+              [xmlel()],
+           %%
+  Rsm      :: boolean(),
+  API_Core :: #api_core{})
+    -> %-- Create_Node --%
+       {result,
+        Module     :: 'pubsub_core' | module(),
+        Function   :: 'create_node',
+        Parameters :: {
+            NodeId      :: undefined | exmpp_pubsub:nodeId(),
+            Node_Config :: [Xmlel::xmlel()]
+        }
+       }
+     | %-- Delete_Node --%
+       {result,
+        Module     :: 'pubsub_core' | module(),
+        Function   :: 'delete_node',
+        Parameters :: {
+            NodeId      :: undefined | exmpp_pubsub:nodeId(),
+            RedirectURI :: undefined | binary()
+        }
+       }
+     | %-- Purge_Node --%
+       {result,
+        Module     :: 'pubsub_core' | module(),
+        Function   :: 'purge_node',
+        Parameters :: {
+            NodeId :: undefined | exmpp_pubsub:nodeId()
+        }
+       }
+     | %-- Publish_Item --%
+       {result,
+        Module     :: 'pubsub_core' | module(),
+        Function   :: 'publish_item',
+        Parameters :: {
+            NodeId          :: undefined | exmpp_pubsub:nodeId(),
+            Item            :: 0,
+            ItemId          :: undefined,
+            Payload         :: exmpp_pubsub:payload_empty(),
+            Node_Config     :: [Xmlel::xmlel()],
+            Publish_Options :: [Xmlel::xmlel()]
+        }
+       }
+     |
+       {result,
+        Module     :: 'pubsub_core' | module(),
+        Function   :: 'publish_item',
+        Parameters :: {
+            NodeId          :: undefined | exmpp_pubsub:nodeId(),
+            Item            :: 1,
+            ItemId          :: undefined | exmpp_pubsub:itemId(),
+            Payload         :: exmpp_pubsub:payload() | [Xmlel::xmlel(),...],
+            Node_Config     :: [Xmlel::xmlel()],
+            Publish_Options :: [Xmlel::xmlel()]
+        }
+       }
+     | %-- Retract_Item --%
+       {result,
+        Module     :: 'pubsub_core' | module(),
+        Function   :: 'retract_item',
+        Parameters :: {
+            NodeId :: undefined | exmpp_pubsub:nodeId(),
+            ItemId :: undefined | exmpp_pubsub:itemId(),
+            Notify :: undefined | boolean()
+        }
+       }
+     | %-- Subscribe_Node --%
+       {result,
+        Module     :: 'pubsub_core' | module(),
+        Function   :: 'subscribe_node',
+        Parameters :: {
+            NodeId            :: undefined | exmpp_pubsub:nodeId(),
+            Jid               :: binary() | undefined,
+            Subscribe_Options :: [Xmlel::xmlel()]
+        }
+       }
+     | %-- Unsubscribe_Node --%
+       {result,
+        Module     :: 'pubsub_core' | module(),
+        Function   :: 'unsubscribe_node',
+        Parameters :: {
+            NodeId :: undefined | exmpp_pubsub:nodeId(),
+            Jid    :: binary() | undefined,
+            SubId  :: undefined | exmpp_pubsub:subId()
+        }
+       }
+     | %-- Set_Configure_Subscription --%
+       {result,
+        Module     :: 'pubsub_core' | module(),
+        Function   :: 'set_configure_subscription',
+        Parameters :: {
+            NodeId            :: undefined | exmpp_pubsub:nodeId(),
+            Jid               :: binary() | undefined,
+            SubId             :: undefined | exmpp_pubsub:subId(),
+            Subscribe_Options :: [Xmlel::xmlel()]
+        }
+       }
+     | %-- Get_Items --%
+       {result,
+        Module     :: 'pubsub_core' | module(),
+        Function   :: 'get_items',
+        Parameters :: {
+            NodeId    :: undefined | exmpp_pubsub:nodeId(),
+            SubId     :: undefined | exmpp_pubsub:subId(),
+            Max_Items :: non_neg_integer(),
+            ItemIds   :: undefined
+        }
+       }
+     |
+       {result,
+        Module     :: 'pubsub_core' | module(),
+        Function   :: 'get_items',
+        Parameters :: {
+            NodeId    :: undefined | exmpp_pubsub:nodeId(),
+            SubId     :: undefined | exmpp_pubsub:subId(),
+            Max_Items :: undefined,
+            ItemIds   :: [] | exmpp_pubsub:itemIds()
+        }
+       }
+     | %-- Get_Entity_Affiliations --%
+       {result,
+        Module     :: 'pubsub_core' | module(),
+        Function   :: 'get_entity_affiliations',
+        Parameters :: {
+            NodeId :: undefined | exmpp_pubsub:nodeId()
+        }
+       }
+     | %-- Get_Entity_Subscriptions --%
+       {result,
+        Module     :: 'pubsub_core' | module(),
+        Function   :: 'get_entity_subscriptions',
+        Parameters :: {
+            NodeId :: undefined | exmpp_pubsub:nodeId()
+        }
+       }
+     | %-- Get_Node_Affiliations --%
+       {result,
+        Module     :: 'pubsub_core' | module(),
+        Function   :: 'get_node_affiliations',
+        Parameters :: {
+            NodeId :: undefined | exmpp_pubsub:nodeId()
+        }
+       }
+     | %-- Get_Node_Subscriptions --%
+       {result,
+        Module     :: 'pubsub_core' | module(),
+        Function   :: 'get_node_subscriptions',
+        Parameters :: {
+            NodeId :: undefined | exmpp_pubsub:nodeId()
+        }
+       }
+     | %-- Get_Configure_Subscription_Default --%
+       {result,
+        Module     :: 'pubsub_core' | module(),
+        Function   :: 'get_configure_subscription_default',
+        Parameters :: {
+            NodeId :: undefined | exmpp_pubsub:nodeId()
+        }
+       }
+     | %-- Get_Configure_Subscription --%
+       {result,
+        Module     :: 'pubsub_core' | module(),
+        Function   :: 'get_configure_subscription',
+        Parameters :: {
+            NodeId :: undefined | exmpp_pubsub:nodeId(),
+            Jid    :: binary() | undefined,
+            SubId  :: undefined | exmpp_pubsub:subId()
+        }
+       }
+     | %-- Get_Configure_Node_Default --%
+       {result,
+        Module     :: 'pubsub_core' | module(),
+        Function   :: 'get_configure_node_default',
+        Parameters :: {
+            NodeId :: undefined | exmpp_pubsub:nodeId()
+        }
+       }
+     | %-- Get_Configure_Node --%
+       {result,
+        Module     :: 'pubsub_core' | module(),
+        Function   :: 'get_configure_node',
+        Parameters :: {
+            NodeId :: undefined | exmpp_pubsub:nodeId()
+        }
+       }
+    %%%
+     | {error, 'invalid-payload'}
+).
+
+%-- Create_Node --%
+
+%% <iq type='set'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%   <create node='princely_musings'/>
+%%  </pubsub>
+%% </iq>
+
+parse('set' = _IQ_Type, [Xmlel_Create], _Rsm, API_Core)
+  when ?Is_Xmlel_Create(Xmlel_Create) ->
+    case xmlns(Xmlel_Create) of
+        ?NS_PUBSUB ->
+            {result,
+             _Module = API_Core#api_core.create_node,
+             _Function = 'create_node',
+             _Parameters = {
+                 _NodeId      = node(Xmlel_Create),
+                 _Node_Config = []
+             }
+            };
+        _ ->
+            {error, 'invalid-payload'}
+    end;
+
+%% <iq type='set'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%   <create node='princely_musings'/>
+%%   <configure>
+%%    <x xmlns='jabber:x:data' type='submit'>
+%%     <field var='FORM_TYPE' type='hidden'>
+%%      <value>http://jabber.org/protocol/pubsub#node_config</value>
+%%     </field>
+%%     <field var='pubsub#title'><value>Princely Musings (Atom)</value></field>
+%%    </x>
+%%   </configure>
+%%  </pubsub>
+%% </iq>
+
+parse('set' = _IQ_Type, [Xmlel_Create, Xmlel_Configure], _Rsm, API_Core)
+  when    ?Is_Xmlel_Create(Xmlel_Create)
+  andalso ?Is_Xmlel_Configure(Xmlel_Configure) ->
+    case {xmlns(Xmlel_Create), xmlns(Xmlel_Configure)} of
+        {NS, NS} when NS == ?NS_PUBSUB ->
+            {result,
+             _Module = API_Core#api_core.create_node,
+             _Function = 'create_node',
+             _Parameters = {
+                 _NodeId      = node(Xmlel_Create),
+                 _Node_Config = remove_cdata(Xmlel_Configure#xmlel.children)
+             }
+            };
+        _ ->
+            {error, 'invalid-payload'}
+    end;
+
+%-- Delete_Node --%
+
+%% <iq type='set'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub#owner'>
+%%   <delete node='princely_musings'/>
+%%  </pubsub>
+%% </iq>
+%%
+%% <iq type='set'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub#owner'>
+%%   <delete node='princely_musings'>
+%%    <redirect uri='xmpp:hamlet@denmark.lit?;node=blog'/>
+%%   </delete>
+%%  </pubsub>
+%% </iq>
+
+parse('set' = _IQ_Type, [Xmlel_Delete], _Rsm, API_Core)
+  when ?Is_Xmlel_Delete(Xmlel_Delete) ->
+    case {xmlns(Xmlel_Delete), remove_cdata(Xmlel_Delete#xmlel.children)} of
+        {?NS_PUBSUB_OWNER, []} ->
+            {result,
+             _Module = API_Core#api_core.delete_node,
+             _Function = 'delete_node',
+             _Parameters = {
+                 _NodeId      = node(Xmlel_Delete),
+                 _RedirectURI = undefined
+             }
+            };
+        {?NS_PUBSUB_OWNER, [Xmlel_Redirect]}
+          when ?Is_Xmlel_Redirect(Xmlel_Redirect) ->
+            case xmlns(Xmlel_Redirect) of
+                ?NS_PUBSUB_OWNER ->
+                    {result,
+                     _Module = API_Core#api_core.delete_node,
+                     _Function = 'delete_node',
+                     _Parameters = {
+                         _NodeId      = node(Xmlel_Delete),
+                         _RedirectURI = uri(Xmlel_Redirect)
+                     }
+                    };
+                _ ->
+                    {error, 'invalid-payload'}
+            end;
+        _ ->
+            {error, 'invalid-payload'}
+    end;
+
+%-- Purge_Node --%
+
+%% <iq type='set'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub#owner'>
+%%   <purge node='princely_musings'/>
+%%  </pubsub>
+%% </iq>
+
+parse('set' = _IQ_Type, [Xmlel_Purge], _Rsm, API_Core)
+  when ?Is_Xmlel_Purge(Xmlel_Purge) ->
+    case xmlns(Xmlel_Purge) of
+        ?NS_PUBSUB_OWNER ->
+            {result,
+             _Module = API_Core#api_core.purge_node,
+             _Function = 'purge_node',
+             _Parameters = {
+                 _NodeId = node(Xmlel_Purge)
+             }
+            };
+        _ ->
+            {error, 'invalid-payload'}
+    end;
+
+%-- Publish_Item --%
+
+%% <iq type='set'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%   <publish node='princely_musings'/>
+%%   <configure>
+%%    <x xmlns='jabber:x:data' type='submit'>
+%%     <field var='FORM_TYPE' type='hidden'>
+%%      <value>http://jabber.org/protocol/pubsub#node_config</value>
+%%     </field>
+%%     <field var='pubsub#title'><value>Princely Musings (Atom)</value></field>
+%%    </x>
+%%   </configure>
+%%   <publish-options>
+%%    <x xmlns='jabber:x:data' type='submit'>
+%%     <field var='FORM_TYPE' type='hidden'>
+%%      <value>http://jabber.org/protocol/pubsub#publish-options</value>
+%%     </field>
+%%     <field var='pubsub#access_model'><value>presence</value></field>
+%%    </x>
+%%   </publish-options>
+%%  </pubsub>
+%% </iq>
+
+%% <iq type='set'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%   <publish node='princely_musings'>
+%%    <item id='bnd81g37d61f49fgn581'/>
+%%   </publish>
+%%   <configure>
+%%    <x xmlns='jabber:x:data' type='submit'>
+%%     <field var='FORM_TYPE' type='hidden'>
+%%      <value>http://jabber.org/protocol/pubsub#node_config</value>
+%%     </field>
+%%     <field var='pubsub#title'><value>Princely Musings (Atom)</value></field>
+%%    </x>
+%%   </configure>
+%%   <publish-options>
+%%    <x xmlns='jabber:x:data' type='submit'>
+%%     <field var='FORM_TYPE' type='hidden'>
+%%      <value>http://jabber.org/protocol/pubsub#publish-options</value>
+%%     </field>
+%%     <field var='pubsub#access_model'><value>presence</value></field>
+%%    </x>
+%%   </publish-options>
+%%  </pubsub>
+%% </iq>
+
+%% <iq type='set'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%   <publish node='princely_musings'>
+%%    <item id='bnd81g37d61f49fgn581'>
+%%     <entry xmlns='http://www.w3.org/2005/Atom'>
+%%      <title>Soliloquy</title>
+%%     </entry>
+%%    </item>
+%%   </publish>
+%%   <publish-options>
+%%    <x xmlns='jabber:x:data' type='submit'>
+%%     <field var='FORM_TYPE' type='hidden'>
+%%      <value>http://jabber.org/protocol/pubsub#publish-options</value>
+%%     </field>
+%%     <field var='pubsub#access_model'><value>presence</value></field>
+%%    </x>
+%%   </publish-options>
+%%  </pubsub>
+%% </iq>
+
+%%
+parse('set' = _IQ_Type, [Xmlel_Publish], _Rsm, API_Core)
+  when ?Is_Xmlel_Publish(Xmlel_Publish) ->
+    case {xmlns(Xmlel_Publish), remove_cdata(Xmlel_Publish#xmlel.children)} of
+        %%
+        {?NS_PUBSUB, []} ->
+            {result,
+             _Module = API_Core#api_core.publish_item,
+             _Function = 'publish_item',
+             _Parameters = {
+                 _NodeId = node(Xmlel_Publish),
+                 _Item = 0,
+                 _ItemId = undefined,
+                 _Payload = [],
+                 _Node_Config = [],
+                 _Publish_Options = []
+             }
+            };
+        %%
+%        [#xmlel{ns = ?NS_PUBSUB, name = 'item'} = Xmlel_Item] ->
+        {?NS_PUBSUB, [#xmlel{name = <<"item">>} = Xmlel_Item]} ->
+            {result,
+             _Module = API_Core#api_core.publish_item,
+             _Function = 'publish_item',
+             _Parameters = {
+                 _NodeId = node(Xmlel_Publish),
+                 _Item = 1,
+                 _ItemId = id(Xmlel_Item),
+                 _Payload = remove_cdata(Xmlel_Item#xmlel.children),
+                 _Node_Config = [],
+                 _Publish_Options = []
+             }
+            };
+        %%
+        _ ->
+            {error, 'invalid-payload'}
+    end;
+%%
+parse('set' = _IQ_Type, [Xmlel_Publish, Xmlel_Configure], _Rsm, API_Core)
+  when    ?Is_Xmlel_Publish(Xmlel_Publish)
+  andalso ?Is_Xmlel_Configure(Xmlel_Configure) ->
+    case {xmlns(Xmlel_Publish), xmlns(Xmlel_Configure)} of
+        {NS, NS} when NS == ?NS_PUBSUB ->
+            case parse('set', [Xmlel_Publish], _Rsm, API_Core) of
+                {result, Module, Function, {NodeId, Item, ItemId, Payload, _, _}} ->
+                    {result,
+                     Module,
+                     Function,
+                     _Parameters = {
+                         NodeId,
+                         Item,
+                         ItemId,
+                         Payload,
+                         _Node_Config = remove_cdata(Xmlel_Configure#xmlel.children),
+                         _Publish_Options = []
+                     }
+                    };
+                Error ->
+                    Error
+            end;
+        _ ->
+            {error, 'invalid-paylaod'}
+    end;
+%%
+parse('set' = _IQ_Type, [Xmlel_Publish, Xmlel_Publish_Options], _Rsm, API_Core)
+  when    ?Is_Xmlel_Publish(Xmlel_Publish)
+  andalso ?Is_Xmlel_Publish_Options(Xmlel_Publish_Options) ->
+    case {xmlns(Xmlel_Publish), xmlns(Xmlel_Publish_Options)} of
+        {NS, NS} when NS == ?NS_PUBSUB ->
+            case parse('set', [Xmlel_Publish], _Rsm, API_Core) of
+                {result, Module, Function, {NodeId, Item, ItemId, Payload, _, _}} ->
+                    {result,
+                     Module,
+                     Function,
+                     _Parameters = {
+                         NodeId,
+                         Item,
+                         ItemId,
+                         Payload,
+                         _Node_Config = [],
+                         _Publish_Options = remove_cdata(
+                             Xmlel_Publish_Options#xmlel.children)
+                     }
+                    };
+                Error ->
+                    Error
+            end;
+        _ ->
+            {error, 'invalid-payload'}
+    end;
+
+%%
+parse('set' = _IQ_Type, [Xmlel_Publish, Xmlel_Configure, Xmlel_Publish_Options],
+  _Rsm, API_Core)
+  when    ?Is_Xmlel_Publish(Xmlel_Publish)
+  andalso ?Is_Xmlel_Configure(Xmlel_Configure)
+  andalso ?Is_Xmlel_Publish_Options(Xmlel_Publish_Options) ->
+    case {xmlns(Xmlel_Publish), xmlns(Xmlel_Configure), xmlns(Xmlel_Publish_Options)} of
+        {NS, NS, NS} when NS == ?NS_PUBSUB ->
+            case parse('set', [Xmlel_Publish, Xmlel_Configure], _Rsm, API_Core) of
+                {result, Module, Function,
+                 {NodeId, Item, ItemId, Payload, Node_Config, _}} ->
+                    {result,
+                     Module,
+                     Function,
+                     _Parameters = {
+                         NodeId,
+                         Item,
+                         ItemId,
+                         Payload,
+                         Node_Config,
+                         _Publish_Options = remove_cdata(
+                             Xmlel_Publish_Options#xmlel.children)
+                     }
+                    };
+                Error ->
+                    Error
+            end;
+        _ ->
+            {error, 'invalid-payload'}
+    end;
+%%
+%%
+parse('set' = _IQ_Type, [Xmlel_Publish, Xmlel_Publish_Options, Xmlel_Configure],
+  Rsm, API_Core)
+  when    ?Is_Xmlel_Publish(Xmlel_Publish)
+  andalso ?Is_Xmlel_Publish_Options(Xmlel_Publish_Options)
+  andalso ?Is_Xmlel_Configure(Xmlel_Configure) ->
+    case {xmlns(Xmlel_Publish), xmlns(Xmlel_Publish_Options), xmlns(Xmlel_Configure)} of
+        {NS, NS, NS} when NS == ?NS_PUBSUB ->
+            parse('set', [Xmlel_Publish, Xmlel_Configure, Xmlel_Publish_Options],
+                Rsm, API_Core);
+        _ ->
+            {error, 'invalid-payload'}
+    end;
+
+%-- Get_Entity_Affiliations --%
+
+%% <iq type='get'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%   <affiliations/>
+%%  </pubsub>
+%% </iq>
+%%
+%% <iq type='get'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%   <affiliations node='princely_musings'/>
+%%  </pubsub>
+%% </iq>
+
+parse('get' = _IQ_Type, [Xmlel_Affiliations], _Rsm, API_Core)
+  when ?Is_Xmlel_Affiliations(Xmlel_Affiliations) ->
+    case xmlns(Xmlel_Affiliations) of
+        ?NS_PUBSUB ->
+            {result,
+             _Module = API_Core#api_core.get_entity_affiliations,
+             _Function = 'get_entity_affiliations',
+             _Parameters = {
+                 _NodeId = node(Xmlel_Affiliations)
+             }
+            };
+        _ ->
+            {error, 'invalid-payload'}
+    end;
+
+%% TODO : RSM
+
+%-- Get_Entity_Subscriptions --%
+
+%% <iq type='get'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%   <subscriptions/>
+%%  </pubsub>
+%% </iq>
+%%
+%% <iq type='get'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%   <subscriptions node='princely_musings'/>
+%%  </pubsub>
+%% </iq>
+
+parse('get' = _IQ_Type, [Xmlel_Subscriptions], _Rsm, API_Core)
+  when ?Is_Xmlel_Subscriptions(Xmlel_Subscriptions) ->
+    case xmlns(Xmlel_Subscriptions) of
+        ?NS_PUBSUB ->
+            {result,
+             _Module = API_Core#api_core.get_entity_subscriptions,
+             _Function = 'get_entity_subscriptions',
+             _Parameters = {
+                 _NodeId = node(Xmlel_Subscriptions)
+             }
+            };
+        _ ->
+            {error, 'invalid-payload'}
+    end;
+
+%% TODO : RSM
+
+%-- Get_Node_Affiliations --%
+
+%% <iq type='get'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub#owner'>
+%%   <affiliations node='princely_musings'/>
+%%  </pubsub>
+%% </iq>
+
+parse('get' = _IQ_Type, [Xmlel_Affiliations], _Rsm, API_Core)
+  when ?Is_Xmlel_Affiliations(Xmlel_Affiliations) ->
+    case xmlns(Xmlel_Affiliations) of
+        ?NS_PUBSUB_OWNER ->
+            {result,
+             _Module = API_Core#api_core.get_node_affiliations,
+             _Function = 'get_node_affiliations',
+             _Parameters = {
+                 _NodeId = node(Xmlel_Affiliations)
+             }
+            };
+        _ ->
+            {error, 'invalid-payload'}
+    end;
+
+%% TODO : RSM
+
+%-- Get_Node_Subscriptions --%
+
+%% <iq type='get'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub#owner'>
+%%   <subscriptions node='princely_musings'/>
+%%  </pubsub>
+%% </iq>
+
+parse('get' = _IQ_Type, [Xmlel_Subscriptions], _Rsm, API_Core)
+  when ?Is_Xmlel_Subscriptions(Xmlel_Subscriptions) ->
+    case xmlns(Xmlel_Subscriptions) of
+        ?NS_PUBSUB_OWNER ->
+            {result,
+             _Module = API_Core#api_core.get_node_subscriptions,
+             _Function = 'get_node_subscriptions',
+             _Parameters = {
+                 _NodeId = node(Xmlel_Subscriptions)
+             }
+            };
+        _ ->
+            {error, 'invalid-payload'}
+    end;
+
+%% TODO : RSM
+
+%-- Retract_Item --%
+
+%% <iq type='set'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%   <retract node='princely_musings'>
+%%    <item id='ae890ac52d0df67ed7cfdf51b644e901'/>
+%%   </retract>
+%%  </pubsub>
+%% </iq>
+%%
+%% <iq type='set'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%   <retract node='princely_musings' notify='true'>
+%%    <item id='ae890ac52d0df67ed7cfdf51b644e901'/>
+%%   </retract>
+%%  </pubsub>
+%% </iq>
+
+parse('set' = _IQ_Type, [Xmlel_Retract], _Rsm, API_Core)
+  when ?Is_Xmlel_Retract(Xmlel_Retract) ->
+    case {xmlns(Xmlel_Retract), notify(Xmlel_Retract)} of
+        {?NS_PUBSUB, undefined} ->
+            {result,
+             _Module = API_Core#api_core.retract_item,
+             _Function = 'retract_item',
+             _Parameters = {
+                 _NodeId = node(Xmlel_Retract),
+                 _ItemId = case remove_cdata(Xmlel_Retract#xmlel.children) of
+                     [Xmlel_Item]
+                       when ?Is_Xmlel_Item(Xmlel_Item) ->
+                         case xmlns(Xmlel_Item) of
+                            ?NS_PUBSUB -> id(Xmlel_Item);
+                            _          -> undefined
+                        end;
+                     _ ->
+                         undefined
+                 
+                 end,
+                 _Notify = undefined
+             }
+            };
+        {?NS_PUBSUB, False}
+          when False == <<"false">> orelse False == <<"0">> ->
+            {result,
+             _Module = API_Core#api_core.retract_item,
+             _Function = 'retract_item',
+             _Parameters = {
+                 _NodeId = node(Xmlel_Retract),
+                 _ItemId = case remove_cdata(Xmlel_Retract#xmlel.children) of
+                     [Xmlel_Item]
+                       when ?Is_Xmlel_Item(Xmlel_Item) ->
+                         case xmlns(Xmlel_Item) of
+                            ?NS_PUBSUB -> id(Xmlel_Item);
+                            _          -> undefined
+                        end;
+                     _ ->
+                         undefined
+                 
+                 end,
+                 _Notify = false
+             }
+            };
+        {?NS_PUBSUB, True}
+          when True == <<"true">> orelse True == <<"1">> ->
+            {result,
+             _Module = API_Core#api_core.retract_item,
+             _Function = 'retract_item',
+             _Parameters = {
+                 _NodeId = node(Xmlel_Retract),
+                 _ItemId = case remove_cdata(Xmlel_Retract#xmlel.children) of
+                     [Xmlel_Item]
+                       when ?Is_Xmlel_Item(Xmlel_Item) ->
+                         case xmlns(Xmlel_Item) of
+                            ?NS_PUBSUB -> id(Xmlel_Item);
+                            _          -> undefined
+                        end;
+                     _ ->
+                         undefined
+                 
+                 end,
+                 _Notify = true
+             }
+            };
+        _ ->
+            {error, 'invalid-payload'}
+    end;
+
+%-- Subscribe_Node --%
+
+%% <iq type='set'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%   <subscribe node='princely_musings' jid='francisco@denmark.lit'/>
+%%  </pubsub>
+%% </iq>
+%%
+%% <iq type='set'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%   <subscribe node='princely_musings' jid='francisco@denmark.lit'/>
+%%   <options>
+%%    <x xmlns='jabber:x:data' type='submit'>
+%%     <field var='FORM_TYPE' type='hidden'>
+%%      <value>http://jabber.org/protocol/pubsub#subscribe_options</value>
+%%     </field>
+%%     <field var='pubsub#deliver'><value>1</value></field>
+%%     <field var='pubsub#show-values'>
+%%      <value>chat</value>
+%%      <value>online</value>
+%%      <value>away</value>
+%%     </field>
+%%    </x>
+%%   </options>
+%%  </pubsub>
+%% </iq>
+
+parse('set' = _IQ_Type, [Xmlel_Subscribe], _Rsm, API_Core)
+  when ?Is_Xmlel_Subscribe(Xmlel_Subscribe) ->
+    case xmlns(Xmlel_Subscribe) of
+        ?NS_PUBSUB ->
+            {result,
+             _Module = API_Core#api_core.subscribe_node,
+             _Function = 'subscribe_node',
+             _Parameters = {
+                 _NodeId = node(Xmlel_Subscribe),
+                 _Jid = id(Xmlel_Subscribe),
+                 _Subscribe_Options = []
+             }
+            };
+        _ ->
+            {error, 'invalid-payload'}
+    end;
+%%
+parse('set' = _IQ_Type, [Xmlel_Subscribe, Xmlel_Options], _Rsm, API_Core)
+  when    ?Is_Xmlel_Subscribe(Xmlel_Subscribe)
+  andalso ?Is_Xmlel_Options1(Xmlel_Options) ->
+    case {xmlns(Xmlel_Subscribe), xmlns(Xmlel_Options)} of
+        {NS, NS} when NS == ?NS_PUBSUB ->
+            {result,
+             _Module = API_Core#api_core.subscribe_node,
+             _Function = 'subscribe_node',
+             _Parameters = {
+                 _NodeId = node(Xmlel_Subscribe),
+                 _Jid = jid(Xmlel_Subscribe),
+                 _Subscribe_Options = remove_cdata(Xmlel_Options#xmlel.children)
+             }
+            };
+        _ ->
+            {error, 'invalid-payload'}
+    end;
+
+%-- Unsubscribe_Node --%
+
+%% <iq type='set'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%   <unsubscribe node='princely_musings' jid='francisco@denmark.lit'/>
+%%  </pubsub>
+%% </iq>
+%%
+%% <iq type='set'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%   <unsubscribe node='princely_musings' jid='francisco@denmark.lit' subid='SubId'/>
+%%  </pubsub>
+%% </iq>
+
+parse('set' = _IQ_Type, [Xmlel_Unsubscribe], _Rsm, API_Core)
+  when ?Is_Xmlel_Unsubscribe(Xmlel_Unsubscribe) ->
+    case xmlns(Xmlel_Unsubscribe) of
+        ?NS_PUBSUB ->
+            {result,
+             _Module = API_Core#api_core.unsubscribe_node,
+             _Function = 'unsubscribe_node',
+             _Parameters = {
+                 _NodeId = node(Xmlel_Unsubscribe),
+                 _Jid = jid(Xmlel_Unsubscribe),
+                 _SubId = subid(Xmlel_Unsubscribe)
+             }
+            };
+        _ ->
+            {error, 'invalid-payload'}
+    end;
+
+%-- Set_Configure_Subscription --%
+
+%% <iq type='set'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%   <options node='princely_musings' jid='francisco@denmark.lit'>
+%%    <x xmlns='jabber:x:data' type='submit'>
+%%     <field var='FORM_TYPE' type='hidden'>
+%%      <value>http://jabber.org/protocol/pubsub#subscribe_options</value>
+%%     </field>
+%%     <field var='pubsub#deliver'><value>1</value></field>
+%%     <field var='pubsub#show-values'>
+%%      <value>chat</value>
+%%      <value>online</value>
+%%      <value>away</value>
+%%     </field>
+%%    </x>
+%%   </options>
+%%  </pubsub>
+%% </iq>
+%%
+%% <iq type='set'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%   <options node='princely_musings' jid='francisco@denmark.lit' subid='SubId'>
+%%    <x xmlns='jabber:x:data' type='submit'>
+%%     <field var='FORM_TYPE' type='hidden'>
+%%      <value>http://jabber.org/protocol/pubsub#subscribe_options</value>
+%%     </field>
+%%     <field var='pubsub#deliver'><value>1</value></field>
+%%     <field var='pubsub#show-values'>
+%%      <value>chat</value>
+%%      <value>online</value>
+%%      <value>away</value>
+%%     </field>
+%%    </x>
+%%   </options>
+%%  </pubsub>
+%% </iq>
+
+parse('set' = _IQ_Type, [Xmlel_Options], _Rsm, API_Core)
+  when ?Is_Xmlel_Options2(Xmlel_Options) ->
+    case xmlns(Xmlel_Options) of
+        ?NS_PUBSUB ->
+            {result,
+             _Module = API_Core#api_core.set_configure_subscription,
+             _Function = 'set_configure_subscription',
+             _Parameters = {
+                 _NodeId = node(Xmlel_Options),
+                 _Jid = jid(Xmlel_Options),
+                 _SubId = subid(Xmlel_Options),
+                 _Subscribe_Options = remove_cdata(Xmlel_Options#xmlel.children)
+             }
+            };
+        _ ->
+            {error, 'invalid-payload'}
+    end;
+
+%-- Get_Items --%
+
+%% <iq type='get'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%   <items node='princely_musings'/>
+%%  </pubsub>
+%% </iq>
+%%
+%% <iq type='get'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%   <items node='princely_musings' max_items='2'/>
+%%  </pubsub>
+%% </iq>
+%%
+%% <iq type='get'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%   <items node='princely_musings'>
+%%    <item id='368866411b877c30064a5f62b917cffe'/>
+%%    <item id='4e30f35051b7b8b42abe083742187228'/>
+%%   </items>
+%%  </pubsub>
+%% </iq>
+
+parse('get' = _IQ_Type, [Xmlel_Items], _Rsm, API_Core)
+  when ?Is_Xmlel_Items1(Xmlel_Items) ->
+    case {xmlns(Xmlel_Items), max_items(Xmlel_Items)} of
+        {?NS_PUBSUB, undefined} ->
+            {result,
+             _Module = API_Core#api_core.get_items,
+             _Function = 'get_items',
+             _Parameters = {
+                 _NodeId = node(Xmlel_Items),
+                 _SubId = subid(Xmlel_Items),
+                 _Max_Items = undefined,
+                 _ItemIds = []
+             }
+            };
+        {?NS_PUBSUB, Binary} ->
+            case catch list_to_integer(binary_to_list(Binary)) of
+                Integer
+                  when is_integer(Integer) andalso Integer >= 0 ->
+                    {result,
+                     _Module = API_Core#api_core.get_items,
+                     _Function = 'get_items',
+                     _Parameters = {
+                         _NodeId = node(Xmlel_Items),
+                         _SubId = subid(Xmlel_Items),
+                         _Max_Items = Integer,
+                         _ItemIds = undefined
+                     }
+                    };
+                _ ->
+                    {error, 'invalid-payload'}
+            end;
+        _ ->
+            {error, 'invalid-payload'}
+    end;
+%%
+parse('get' = _IQ_Type, [Xmlel_Items], _Rsm, API_Core)
+  when ?Is_Xmlel_Items2(Xmlel_Items) ->
+    case
+        {xmlns(Xmlel_Items),
+         parse_xmlels_item(remove_cdata(Xmlel_Items#xmlel.children))}
+    of
+        {?NS_PUBSUB, {ok, ItemIds}} ->
+            {result,
+             _Module = API_Core#api_core.get_items,
+             _Function = 'get_items',
+             _Parameters = {
+                 _NodeId = node(Xmlel_Items),
+                 _SubId = subid(Xmlel_Items),
+                 _Max_Items = undefined,
+                 ItemIds
+             }
+            };
+        {_, _Error} ->
+            {error, 'invalid-payload'}
+    end;
+
+%-- Get_Configure_Subscription_Default --%
+
+%% <iq type='get'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%   <default/>
+%%  </pubsub>
+%% </iq>
+%%
+%% <iq type='get'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%   <default node='princely_musings'/>
+%%  </pubsub>
+%% </iq>
+
+parse('get' = _IQ_Type, [Xmlel_Default], _Rsm, API_Core)
+  when ?Is_Xmlel_Default(Xmlel_Default) ->
+    case xmlns(Xmlel_Default) of
+        ?NS_PUBSUB ->
+            {result,
+             _Module = API_Core#api_core.get_configure_subscription_default,
+             _Function = 'get_configure_subscription_default',
+             _Parameters = {
+                 _NodeId = node(Xmlel_Default)
+             }
+            };
+        _ ->
+            {error, 'invalid-payload'}
+    end;
+
+%-- Get_Configure_Subscription --%
+
+%% <iq type='get'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%    <options node='princely_musings' jid='francisco@denmark.lit'/>
+%%  </pubsub>
+%% </iq>
+%%
+%% <iq type='get'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
+%%    <options node='princely_musings' jid='francisco@denmark.lit' subid='SubId'/>
+%%  </pubsub>
+%% </iq>
+
+parse('get' = _IQ_Type, [Xmlel_Options], _Rsm, API_Core)
+  when ?Is_Xmlel_Options2(Xmlel_Options) ->
+    case xmlns(Xmlel_Options) of
+        ?NS_PUBSUB ->
+            {result,
+             _Module = API_Core#api_core.get_configure_subscription,
+             _Function = 'get_configure_subscription',
+             _Parameters = {
+                 _NodeId = node(Xmlel_Options),
+                 _Jid = jid(Xmlel_Options),
+                 _SubId = subid(Xmlel_Options)
+             }
+            };
+        _ ->
+            {error, 'invalid-payload'}
+    end;
+
+%-- Get_Configure_Node_Default --%
+
+%% <iq type='get'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub#owner'>
+%%   <default/>
+%%  </pubsub>
+%% </iq>
+
+parse('get' = _IQ_Type, [Xmlel_Default], _Rsm, API_Core)
+  when ?Is_Xmlel_Default(Xmlel_Default) ->
+    case xmlns(Xmlel_Default) of
+        ?NS_PUBSUB_OWNER ->
+            {result,
+             _Module = API_Core#api_core.get_configure_node_default,
+             _Function = 'get_configure_node_default',
+             _Parameters = {
+                 _NodeId = node(Xmlel_Default)
+             }
+            };
+        _ ->
+            {error, 'invalid-payload'}
+    end;
+
+%-- Get_Configure_Node --%
+
+%% <iq type='get'>
+%%  <pubsub xmlns='http://jabber.org/protocol/pubsub#owner'>
+%%    <configure node='princely_musings'/>
+%%  </pubsub>
+%% </iq>
+
+parse('get' = _IQ_Type, [Xmlel_Configure], _Rsm, API_Core)
+  when ?Is_Xmlel_Configure(Xmlel_Configure) ->
+    case xmlns(Xmlel_Configure) of
+        ?NS_PUBSUB_OWNER ->
+            {result,
+             _Module = API_Core#api_core.get_configure_node,
+             _Function = 'get_configure_node',
+             _Parameters = {
+                 _NodeId = node(Xmlel_Configure)
+             }
+            };
+        _ ->
+            {error, 'invalid-payload'}
+    end;
+
+%%
+parse(_IQ_Type, _Xmlels, _Rsm, _API_Core) ->
+    {error, 'invalid-payload'}.
+
+
+
+%%%%%%%%%%%%%%%%%%%%%
+%% Parsing Helpers %%
+%%%%%%%%%%%%%%%%%%%%%
+
+
+%%
+-spec(parse_xmlels_item/1 ::
+(
+  Xmlels  :: [Xmlel_Item::xmlel(),...])
+    -> {ok, ItemIds :: [] | exmpp_pubsub:itemIds()}
+    %%%
+     | {error, 'invalid-payload'}
+).
+
+parse_xmlels_item(Xmlels) ->
+    parse_xmlels_item(Xmlels, []).
+
+%%
+-spec(parse_xmlels_item/2 ::
+(
+  Xmlels  :: [Xmlel_Item::xmlel(),...],
+  ItemIds :: [] | exmpp_pubsub:itemIds())
+    -> {ok, ItemIds :: [] | exmpp_pubsub:itemIds()}
+    %%%
+     | {error, 'invalid-payload'}
+).
+
+
+%%
+parse_xmlels_item([Xmlel_Item | Xmlels], ItemIds)
+  when ?Is_Xmlel_Item(Xmlel_Item) ->
+    case {xmlns(Xmlel_Item), id(Xmlel_Item)} of
+        {?NS_PUBSUB, ItemId}
+          when ItemId /= undefined ->
+            parse_xmlels_item(Xmlels, [ItemId | ItemIds]);
+        _ ->
+            {error, 'invalid-payload'}
+    end;
+parse_xmlels_item([] = _Xmlels_Item, ItemIds) ->
+    {ok, ItemIds};
+%%
+parse_xmlels_item(_Xmlels, _ItemIds) ->
+    {error, 'invalid-payload'}.
+
+
+xmlns(Xmlel) ->
+    get_tag_attr_s(<<"xmlns">>, Xmlel).
+
+node(Xmlel) ->
+    case get_tag_attr_s(<<"node">>, Xmlel) of
+        <<>>   -> undefined;
+        NodeId -> NodeId
+    end.
+
+id(Xmlel) ->
+    case get_tag_attr_s(<<"id">>, Xmlel) of
+        <<>>   -> undefined;
+        ItemId -> ItemId
+    end.
+
+uri(Xmlel) ->
+    case get_tag_attr_s(<<"uri">>, Xmlel) of
+        <<>> -> undefined;
+        URI  -> URI
+    end.
+
+jid(Xmlel) ->
+    case get_tag_attr_s(<<"jid">>, Xmlel) of
+        <<>> -> undefined;
+        Jid  -> Jid
+    end.
+
+subid(Xmlel) ->
+    case get_tag_attr_s(<<"subid">>, Xmlel) of
+        <<>>  -> undefined;
+        SubId -> SubId
+    end.
+
+notify(Xmlel) ->
+    case get_tag_attr_s(<<"notify">>, Xmlel) of
+        <<>>   -> undefined;
+        Notify -> Notify
+    end.
+
+max_items(Xmlel) ->
+    case get_tag_attr_s(<<"max_items">>, Xmlel) of
+        <<>>      -> undefined;
+        Max_Items -> Max_Items
+    end.
diff --git a/src/mod_pubsub_ng/pubsub_tools.erl b/src/mod_pubsub_ng/pubsub_tools.erl
new file mode 100644
index 000000000..9bb5d2504
--- /dev/null
+++ b/src/mod_pubsub_ng/pubsub_tools.erl
@@ -0,0 +1,685 @@
+%%% ====================================================================
+%%% ``The contents of this file are subject to the Erlang Public License,
+%%% Version 1.1, (the "License"); you may not use this file except in
+%%% compliance with the License. You should have received a copy of the
+%%% Erlang Public License along with this software. If not, it can be
+%%% retrieved via the world wide web at http://www.erlang.org/.
+%%% 
+%%% Software distributed under the License is distributed on an "AS IS"
+%%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%%% the License for the specific language governing rights and limitations
+%%% under the License.
+%%% 
+%%% The Initial Developer of the Original Code is ProcessOne.
+%%% Portions created by ProcessOne are Copyright 2006-2011, ProcessOne
+%%% All Rights Reserved.''
+%%% This software is copyright 2006-2011, ProcessOne.
+%%%
+%%% @copyright 2006-2011 ProcessOne
+%%% @author Karim Gemayel <karim.gemayel@process-one.net>
+%%%   [http://www.process-one.net/]
+%%% @version {@vsn}, {@date} {@time}
+%%% @end
+%%% ====================================================================
+
+%%% @headerfile "pubsub_dev.hrl"
+
+-module(pubsub_tools).
+-author('karim.gemayel@process-one.net').
+
+-compile(export_all).
+
+-include("pubsub_dev.hrl").
+
+jid_to_string({undefined, S, undefined}) ->
+    jlib:jid_to_string({<<>>, S, <<>>});
+jid_to_string({undefined, S, R}) ->
+    jlib:jid_to_string({<<>>, S, R});
+jid_to_string({U, S, undefined}) ->
+    jlib:jid_to_string({U, S, <<>>});
+jid_to_string(USR) ->
+    jlib:jid_to_string(USR).
+
+make_jid({undefined, S, undefined}) ->
+    jlib:make_jid(<<>>, S, <<>>);
+make_jid({U, S, undefined}) ->
+    jlib:make_jid({U, S, <<>>});
+make_jid(Entity) ->
+    jlib:make_jid(Entity).
+
+%% @doc Determine if data is a JID
+-spec(is_jid/1 ::
+(
+  Data :: binary() | undefined)
+    -> xmpp_jid:entity() | {error, 'jid-malformed'}
+).
+
+is_jid(Data) ->
+    try jlib:string_to_jid(Data) of
+        #jid{} = Jid -> Jid
+    catch
+        _Error -> {error, 'jid-malformed'}
+    end.
+
+%%%
+%-spec(get_value/2 ::
+%(
+%  Options :: {Node_Options :: pubsub_options:options_node(),
+%              Item_Options :: [] | pubsub_options:options_item()}
+%           | pubsub_options:options_item()
+%           | pubsub_options:options_node()
+%           | pubsub_options:options_subscription()
+%           | [],
+%  Key     :: atom())
+%    -> Value :: atom()
+%              | binary()
+%              | boolean()
+%              | non_neg_integer()
+%              | undefined
+%              | []
+%              | 'none'
+%              | [atom(),...]
+%              | [binary(),...]
+%              | [boolean(),...]
+%              | [non_neg_integer(),...]
+%).
+
+get_value({Node_Options, [] = _Item_Options}, Key) ->
+    get_value(Node_Options, Key, 0);
+%%
+get_value({Node_Options, Item_Options}, Key) ->
+    case get_value(Item_Options, Key, 'none') of
+        'none' -> get_value(Node_Options, Key, false);
+        Value -> Value
+    end;
+%%
+get_value([], _Key) -> 'none';
+%%
+get_value(Options, Key) ->
+    get_value(Options, Key, 'none').
+
+%%%
+%-spec(get_value/3 ::
+%(
+%  Options :: {Node_Options :: pubsub_options:options_node(),
+%              Item_Options :: [] | pubsub_options:options_item()}
+%           | pubsub_options:options_item()
+%           | pubsub_options:options_node()
+%           | pubsub_options:options_subscription(),
+%  Key     :: atom(),
+%  Default :: term())
+%    -> Value :: atom()
+%              | binary()
+%              | boolean()
+%              | non_neg_integer()
+%              | undefined
+%              | []
+%              | [atom(),...]
+%              | [binary(),...]
+%              | [boolean(),...]
+%              | [non_neg_integer(),...]
+%).
+get_value({Node_Options, [] = _Item_Options}, Key, Default) ->
+    get_value(Node_Options, Key, Default);
+%%
+get_value({Node_Options, Item_Options}, Key, Default) ->
+    case get_value(Item_Options, Key, 'none') of
+        'none' -> get_value(Node_Options, Key, Default);
+        Value  -> Value
+    end;
+%%
+get_value(Options, Key, Default) ->
+    case lists:keyfind(Key, 1, Options) of
+        {_Key, Value} -> Value;
+        false         -> Default
+    end.
+
+%%%
+%-spec(set_value/3 ::
+%(
+%  Options :: pubsub_options:options_item()
+%           | pubsub_options:options_node()
+%           | pubsub_options:options_subscription(),
+%  Key     :: atom(),
+%  Value   :: atom()
+%           | binary()
+%           | boolean()
+%           | non_neg_integer()
+%           | undefined
+%           | []
+%           | [atom(),...]
+%           | [binary(),...]
+%           | [boolean(),...]
+%           | [non_neg_integer(),...])
+%    -> Options :: pubsub_options:options_item()
+%                | pubsub_options:options_node()
+%                | pubsub_options:options_subscription()
+%).
+
+set_value(Options, Key, Value) ->
+    lists:keyreplace(Key, 1, Options, {Key, Value}).
+
+%%
+
+%-spec(get_option/2 ::
+%(
+%  Options :: {Node_Options :: pubsub_options:options_node(),
+%              Item_Options :: [] | pubsub_options:options_item()}
+%           | pubsub_options:options_item()
+%           | pubsub_options:options_node()
+%           | pubsub_options:options_subscription()
+%           | [],
+%  Key     :: atom())
+%    -> Option :: pubsub_options:option_item()
+%               | pubsub_options:option_node()
+%               | pubsub_options:option_subscription()
+%               | 'none'
+%).
+
+get_option({Node_Options, [] = _Item_Options}, Key) ->
+    get_option(Node_Options, Key, 'none');
+%%
+get_option({Node_Options, Item_Options}, Key) ->
+    case get_option(Item_Options, Key, 'none') of
+        'none' -> get_option(Node_Options, Key, 'none');
+        Option -> Option
+    end;
+%%
+get_option([], _Key) -> 'none';
+%%
+get_option(Options, Key) ->
+    get_option(Options, Key, 'none').
+
+%%%
+%-spec(get_option/3 ::
+%(
+%  Options :: {Node_Options :: pubsub_options:options_node(),
+%              Item_Options :: [] | pubsub_options:options_item()}
+%           | pubsub_options:options_item()
+%           | pubsub_options:options_node()
+%           | pubsub_options:options_subscription(),
+%  Key     :: atom(),
+%  Default :: term())
+%    -> Option :: pubsub_options:option_item()
+%               | pubsub_options:option_node()
+%               | pubsub_options:option_subscription()
+%               | term()
+%).
+
+get_option({Node_Options, [] = _Item_Options}, Key, Default) ->
+    get_option(Node_Options, Key, Default);
+%%
+get_option({Node_Options, Item_Options}, Key, Default) ->
+    case get_option(Item_Options, Key, 'none') of
+        'none'  -> get_option(Node_Options, Key, Default);
+        Option  -> Option
+    end;
+%%
+get_option(Options, Key, Default) ->
+    case lists:keyfind(Key, 1, Options) of
+        {_Key, Value} -> _Option = {Key, Value};
+        false         -> Default
+    end.
+
+%%
+-spec(get_entity_roster/1 ::
+(
+  Entity :: xmpp_jid:usr_entity()
+          | xmpp_jid:entity())
+    ->  Roster::[Roster_Item::#roster{}]
+).
+
+get_entity_roster({U,S, _R} = _USR_Entity) ->
+    _Roster = ejabberd_hooks:run_fold(roster_get, S, [], [{U,S}]);
+get_entity_roster(#jid{luser = U, lserver = S} = _Jid_Entity) ->
+    _Roster = get_entity_roster({U,S, undefined}).
+
+%%
+-spec(check_access_model/3 ::
+(
+  Host     :: xmpp_jid:raw_jid_component_bare(),
+  Entity   :: xmpp_jid:usr_entity(),
+  Criteria :: {Access_Model           :: pubsub_options:access_model(),
+               Affiliation            :: exmpp_pubsub:affiliation(),
+               Subscriptions          :: exmpp_pubsub:subscriptions(),
+               Node_Owners            :: [Node_Owner::xmpp_jid:usr_bare(),...],
+               Rosters_Groups_Allowed :: pubsub_options:rosters_groups_allowed()})
+    -> ok
+    %%%
+     | {error, 'forbidden'}
+).
+
+check_access_model(_Host, _Entity,
+  {_Access_Model, 'outcast' = _Affiliation, _Subscriptions, _Node_Owners,
+   _Rosters_Groups_Allowed}) ->
+    {error, 'forbidden'};
+%%
+check_access_model(_Host, _Entity,
+  {'open' = _Access_Model, _Affiliation, _Subscriptions, _Node_Owners,
+   _Rosters_Groups_Allowed}) ->
+    ok;
+%%
+check_access_model(Host, Entity,
+  {'presence' = _Access_Model, _Affiliation, _Subscriptions, Node_Owners,
+   _Rosters_Groups_Allowed}) ->
+    case is_contact_subscribed_to_node_owners(Host, Entity, Node_Owners) of
+        false ->
+            {error, 'forbidden'};
+        _Node_Owner ->
+            ok
+    end;
+%%
+check_access_model(_Host, Entity,
+  {'roster' = _Access_Model, _Affiliation, _Subscriptions, _Node_Owners,
+   Rosters_Groups_Allowed}) ->
+    case is_contact_in_allowed_roster_groups(Entity, Rosters_Groups_Allowed) of
+        false ->
+            {error, 'forbidden'};
+        {_Node_Owner, _Roster_Group_Allowed} ->
+            ok
+    end;
+%%
+check_access_model(_Host, _Entity,
+  {'whitelist' = _Access_Model, Affiliation, _Subscriptions, _Node_Owners,
+   _Roster_Groups_Allowed})
+  when Affiliation == 'member'
+  %%orelse Affiliation == 'owner'
+  orelse Affiliation == 'publish-only'
+  orelse Affiliation == 'publisher' ->
+    ok;
+check_access_model(_Host, _Entity,
+  {'whitelist' = _Access_Model, _Affiliation, _Subscriptions, _Node_Owners,
+   _Roster_Groups_Allowed}) ->
+    {error, 'forbidden'};
+%%
+check_access_model(_Host, _Entity,
+  {'authorize' = _Access_Model, _Affiliation, Subscriptions, _Node_Owners,
+   _Roster_Groups_Allowed}) ->
+    case has_subscriptions(Subscriptions) of
+        true  -> ok;
+        false -> {error, 'forbidden'}
+    end.
+
+
+
+%%
+-spec(check_access_model/7 ::
+(
+  Host                   :: xmpp_jid:raw_jid_component_bare(),
+  Entity                 :: xmpp_jid:usr_entity(),
+  Access_Model           :: pubsub_options:access_model(),
+  Affiliation            :: exmpp_pubsub:affiliation(),
+  Subscriptions          :: exmpp_pubsub:subscriptions(),
+  Node_Owners            :: [Node_Owner::xmpp_jid:usr_bare(),...],
+  Rosters_Groups_Allowed :: pubsub_options:rosters_groups_allowed())
+    -> ok
+    %%%
+     | {error, 'forbidden'}
+     | {error, 'item-not-found'}
+).
+
+check_access_model(_Host, _Entity, _Access_Model, 'owner' = _Affiliation,
+  _Subscriptions, _Node_Owners, _Rosters_Groups_Allowed) ->
+    ok;
+%%
+check_access_model(Host, Entity, Access_Model, 'outcast' = _Affiliation,
+  _Subscriptions, Node_Owners, Rosters_Groups_Allowed) ->
+    case Access_Model of
+        %%
+        'open'->
+              {error, 'forbidden'};
+        %%
+        'presence' ->
+            case
+                is_contact_subscribed_to_node_owners(Host, Entity, Node_Owners)
+            of
+                false ->
+                    {error, 'item-not-found'};
+                _Node_Owner ->
+                    {error, 'forbidden'}
+            end;
+        %%
+        'roster' ->
+            case
+                is_contact_in_allowed_roster_groups(Entity,
+                    Rosters_Groups_Allowed)
+            of
+                false ->
+                    {error, 'item-not-found'};
+                {_Node_Owner, _Roster_Group_Allowed} ->
+                    {error, 'forbidden'}
+            end;
+        %%
+        'authorize' ->
+            {error, 'forbidden'};
+        %%
+        'whitelist' ->
+            {error, 'item-not-found'}
+    end;
+%%
+check_access_model(_Host, _Entity, 'open' = _Access_Model, _Affiliation,
+  _Subscriptions, _Node_Owners, _Rosters_Groups_Allowed) ->
+    ok;
+%%
+check_access_model(Host, Entity, 'presence' = _Access_Model, _Affiliation,
+  _Subscriptions, Node_Owners, _Rosters_Groups_Allowed) ->
+    case is_contact_subscribed_to_node_owners(Host, Entity, Node_Owners) of
+        false ->
+            {error, 'item-not-found'};
+        _Node_Owner ->
+            ok
+    end;
+%%
+check_access_model(_Host, Entity, 'roster' = _Access_Model, _Affiliation,
+  _Subscriptions, _Node_Owners, Rosters_Groups_Allowed) ->
+    case is_contact_in_allowed_roster_groups(Entity, Rosters_Groups_Allowed) of
+        false ->
+            {error, 'item-not-found'};
+        {_Node_Owner, _Roster_Group_Allowed} ->
+            ok
+    end;
+%%
+check_access_model(_Host, _Entity, 'whitelist' = _Access_Model, Affiliation,
+  _Subscriptions, _Node_Owners, _Roster_Groups_Allowed) ->
+    case Affiliation of
+        Affiliation
+          when   Affiliation == 'member'
+          orelse Affiliation == 'publish-only'
+          orelse Affiliation == 'publisher' ->
+            ok;
+        _Affiliation ->
+            {error, 'item-not-found'}
+    end;
+%%
+check_access_model(_Host, _Entity, 'authorize' = _Access_Model, _Affiliation,
+  Subscriptions, _Node_Owners, _Roster_Groups_Allowed) ->
+    case has_subscriptions(Subscriptions) of
+        true  ->
+            ok;
+        false ->
+            {error, 'item-not-found'}
+    end.
+
+
+-spec(check_publish_model/3 ::
+(
+  Publish_Model :: pubsub_options:publish_model(),
+  Affiliation   :: exmpp_pubsub:affiliation(),
+  Subscriptions :: exmpp_pubsub:subscriptions())
+    -> ok
+    %%%
+     | {error, 'forbidden'}
+).
+
+check_publish_model('open' = _Publish_Model, _Affiliation, _Subscriptions) ->
+    ok;
+%%
+check_publish_model('publishers' = _Publish_Model, Affiliation, _Subscriptions) ->
+    case Affiliation of
+        Affiliation
+          when   Affiliation == 'owner'
+          orelse Affiliation == 'publish-only'
+          orelse Affiliation == 'publisher' ->
+            ok;
+        _Affiliation ->
+            {error, 'forbidden'}
+    end;
+%%
+check_publish_model('subscribers' = _Publish_Model, Affiliation, Subscriptions) ->
+    case Affiliation of
+        'owner' ->
+            ok;
+        _Affiliation ->
+            case has_subscriptions(Subscriptions) of
+                true ->
+                    ok;
+                false ->
+                    {error, 'forbidden'}
+            end
+    end.
+
+%%
+-spec(has_subscriptions/1 ::
+(
+  Subscriptions :: exmpp_pubsub:subscriptions())
+    -> Has_Subscriptions::boolean()
+).
+
+has_subscriptions([] = _Subscriptions) ->
+    false;
+has_subscriptions(
+  [{'pending' = _Subscription_State, _SubId, _Resource, _Subscription_Options}]) ->
+    false;
+has_subscriptions(_Subscriptions) ->
+    true.
+
+%%
+%% @doc Check if a contact is subscribed to at least one local node owner
+%%      amongst a list of (remote and local) node owners
+-spec(is_contact_subscribed_to_node_owners/3 ::
+(
+  Host        :: xmpp_jid:raw_jid_component_bare(),
+  Contact     :: xmpp_jid:usr_entity(),
+  Node_Owners :: [] | [Node_Owner::xmpp_jid:usr_bare(),...])
+    -> Is_Contact_Subscribed_To_Node_Owners :: false | xmpp_jid:usr_bare()
+).
+
+is_contact_subscribed_to_node_owners(_Host, _Contact, [] = _Node_Owners) ->
+    false;
+%% The node owner is a local entity, check if the contact is subscribed to it
+is_contact_subscribed_to_node_owners(Host, Contact,
+  [{_U, Host, _R} = Local_Node_Owner | Node_Owners] = _Node_Owners) ->
+    _Is_Contact_Subscribed_To_Node_Owners = case
+        is_contact_subscribed_to_entity(Contact,
+            _Local_Node_Owner_Roster = get_entity_roster(Local_Node_Owner))
+    of
+        true ->
+            Local_Node_Owner;
+        false ->
+            is_contact_subscribed_to_node_owners(Host, Contact, Node_Owners)
+    end;
+%% The node owner is a remote entity, don't check if the contact is subscribed to it
+is_contact_subscribed_to_node_owners(Host, Contact,
+  [_Remote_Node_Owner | Node_Owners] = _Node_Owners) ->
+    is_contact_subscribed_to_node_owners(Host, Contact, Node_Owners).
+
+%%
+%% @doc Check if an entity is in a #roster{}
+%%      with #roster.subscription == 'from' or
+%%      with #roster.subscription == 'both'
+-spec(is_contact_subscribed_to_entity/2 ::
+(
+  Contact       :: xmpp_jid:usr_entity(),
+  Entity_Roster :: [] | [Roster_Item::#roster{},...])
+    -> Is_Contact_Subscribed::boolean()
+).
+
+is_contact_subscribed_to_entity(_Contact, [] = _Entity_Roster) ->
+    _Is_Contact_Subscribed = false;
+%% Contact is included in a #roster{} item with
+%% a subscription of type 'from' and 'both' (i.e. is subscribed to it)
+is_contact_subscribed_to_entity({U, S, _R} = _Contact,
+  [#roster{jid = {U, S, _}, subscription = Subscription} = _Roster_Item
+  | _Roster_Items] = _Entity_Roster)
+   when Subscription == 'from' orelse Subscription == 'both' ->
+    _Is_Contact_Subscribed = true;
+%% Contact is not included in a #roster{} item
+%% or has a subscription of type different than 'from' and 'both'
+%% ( i.e. is not subscribed to it),
+%% check next roster items
+is_contact_subscribed_to_entity(Contact,
+  [_Roster_Item | Roster_Items] = _Entity_Roster) ->
+    _Is_Contact_Subscribed = is_contact_subscribed_to_entity(Contact,
+        Roster_Items).
+
+%%
+-spec(is_contact_in_allowed_roster_groups/2 ::
+(
+  Contact                :: xmpp_jid:usr_entity(),
+  Rosters_Groups_Allowed :: pubsub_options:rosters_groups_allowed())
+    -> Roster_Group_Allowed :: false
+                             | {Entity       :: xmpp_jid:usr_bare(),
+                                Roster_Group :: pubsub_options:roster_group()}
+).
+
+is_contact_in_allowed_roster_groups(_Contact, [] = _Rosters_Groups_Allowed) ->
+    false;
+%%
+is_contact_in_allowed_roster_groups(Contact,
+  [{Entity, Entity_Roster_Groups_Allowed} | Rosters_Groups_Allowed]
+  = _Rosters_Groups_Allowed) ->
+    case
+        is_contact_in_allowed_roster_group(Contact,
+            _Entity_Roster = get_entity_roster(Entity),
+            Entity_Roster_Groups_Allowed)
+    of
+        false ->
+            is_contact_in_allowed_roster_groups(Contact, Rosters_Groups_Allowed);
+        Roster_Group ->
+            {Entity, Roster_Group}
+    end.
+
+%%
+-spec(is_contact_in_allowed_roster_group/3 ::
+(
+  Contact               :: xmpp_jid:usr_entity(),
+  Entity_Roster         :: [] | [Roster_Item::#roster{groups::pubsub_options:roster_groups()}],
+  Roster_Groups_Allowed :: [Roster_Group_Allowed::pubsub_options:roster_group(),...])
+    -> Roster_Group :: false | pubsub_options:roster_group()
+).
+
+is_contact_in_allowed_roster_group(_Contact, [] = _Entity_Roster,
+  _Roster_Groups_Allowed) ->
+    false;
+%%
+is_contact_in_allowed_roster_group({U, S, _R} = _Contact,
+  [#roster{jid = {U, S, _}, subscription = Subscription, groups = Roster_Groups}
+  | _Other_Roster_Items] = _Entity_Roster, Roster_Groups_Allowed)
+  when Subscription == 'from' orelse Subscription == 'both' ->
+    is_contact_in_allowed_roster_group(Roster_Groups, Roster_Groups_Allowed);
+%%
+is_contact_in_allowed_roster_group(Contact,
+  [_Roster_Item | Roster_Items] = _Entity_Roster, Roster_Groups_Allowed) ->
+    is_contact_in_allowed_roster_group(Contact, Roster_Items,
+        Roster_Groups_Allowed).
+
+%%
+-spec(is_contact_in_allowed_roster_group/2 ::
+(
+  Roster_Groups         :: [] | [Roster_Group::pubsub_options:roster_group()],
+  Roster_Groups_Allowed :: [Roster_Group_Allowed::pubsub_options:roster_group(),...])
+    -> Roster_Group :: false | pubsub_options:roster_group()
+).
+
+is_contact_in_allowed_roster_group([] = _Roster_Groups, _Roster_Groups_Allowed) ->
+    false;
+%%
+is_contact_in_allowed_roster_group([Roster_Group | Roster_Groups]
+  = _Roster_Groups, Roster_Groups_Allowed) ->
+    case lists:member(Roster_Group, Roster_Groups_Allowed) of
+        true ->
+            Roster_Group;
+        false ->
+            is_contact_in_allowed_roster_group(Roster_Groups,
+                Roster_Groups_Allowed)
+    end.
+
+%%
+-spec(get_user_resources/2 ::
+(
+  User   :: binary(),
+  Server :: binary())
+    -> Resources::[Resource::xmpp_jid:resource_jid()]
+).
+
+get_user_resources(User, Server) ->
+    ejabberd_sm:get_user_resources(User, Server).
+
+%%
+-spec(get_resources_show/2 ::
+(
+  User   :: binary(),
+  Server :: binary())
+    -> Resources_Show :: [{Resource :: xmpp_jid:resource_jid(),
+                           Show :: 'away' | 'chat' | 'dnd' | 'online' | 'xa' }]
+).
+
+get_resources_show(User, Server) ->
+    _Resources_Show = lists:foldl(fun
+        (Resource, Resources_Show) ->
+            case ejabberd_sm:get_session_pid(User, Server, Resource) of
+                C2SPid when is_pid(C2SPid) ->
+                    case ejabberd_c2s:get_presence(C2SPid) of
+                        {_User, _Resource, Show, _} ->
+                            [{Resource, list_to_atom(Show)} | Resources_Show];
+                        _ ->
+                            Resources_Show
+                    end;
+                _  ->
+                    Resources_Show
+            end
+    end, [], _Resources = ejabberd_sm:get_user_resources(User, Server)).
+
+
+%%
+-spec(rosters_groups_allowed_cache/2 ::
+(
+  Rosters_Groups_Allowed       :: pubsub_options:rosters_groups_allowed(),
+  Rosters_Groups_Allowed_Cache :: pubsub_options:rosters_groups_allowed())
+    -> Is_Roster_Groups_Cached::boolean()
+).
+
+rosters_groups_allowed_cache(_Rosters_Groups_Allowed,
+  [] = _Rosters_Groups_Allowed_Cache) ->
+    false;
+%%
+rosters_groups_allowed_cache([] = _Rosters_Groups_Allowed,
+  _Rosters_Groups_Allowed_Cache) ->
+    false;
+%%
+rosters_groups_allowed_cache(
+  [{Entity, Roster_Groups_Allowed} | Rosters_Groups_Allowed],
+  Rosters_Groups_Allowed_Cache) ->
+    case lists:keyfind(Entity, 1, Rosters_Groups_Allowed_Cache) of
+        {_Entity, Roster_Groups_Allowed_Cache} ->
+            case
+                roster_groups_allowed_cache(Roster_Groups_Allowed,
+                    Roster_Groups_Allowed_Cache)
+            of
+                true ->
+                    true;
+                false ->
+                    rosters_groups_allowed_cache(Rosters_Groups_Allowed,
+                        Rosters_Groups_Allowed_Cache)
+            end;
+        false ->
+            rosters_groups_allowed_cache(Rosters_Groups_Allowed,
+                Rosters_Groups_Allowed_Cache)
+    end.
+
+%%
+-spec(roster_groups_allowed_cache/2 ::
+(
+  Roster_Groups_Allowed       :: [Roster_Group_Allowed::pubsub_options:roster_group()],
+  Roster_Groups_Allowed_Cache :: [Roster_Group_Allowed_Cache::pubsub_options:roster_group()])
+    -> Is_Roster_Groups_Cached :: boolean()
+).
+
+roster_groups_allowed_cache(_Roster_Groups_Allowed,
+  [] = _Roster_Groups_Allowed_Cache) ->
+    false;
+%%
+roster_groups_allowed_cache([] = _Roster_Groups_Allowed,
+  _Roster_Groups_Allowed_Cache) ->
+    false;
+%%
+roster_groups_allowed_cache([Roster_Group_Allowed | Roster_Groups_Allowed],
+  Roster_Groups_Allowed_Cache) ->
+    case lists:member(Roster_Group_Allowed, Roster_Groups_Allowed_Cache) of
+        true ->
+            true;
+        false ->
+            roster_groups_allowed_cache(Roster_Groups_Allowed,
+                Roster_Groups_Allowed_Cache)
+    end.
+
diff --git a/src/mod_pubsub_ng/xmpp_xdata.erl b/src/mod_pubsub_ng/xmpp_xdata.erl
new file mode 100644
index 000000000..879549c46
--- /dev/null
+++ b/src/mod_pubsub_ng/xmpp_xdata.erl
@@ -0,0 +1,108 @@
+-module(xmpp_xdata).
+
+
+-include("jlib.hrl").
+-include("ejabberd.hrl").
+-compile(export_all).
+
+xmlcdata(CData) ->
+    {xmlcdata, CData}.
+
+xmlattr(Name, Value) ->
+%    #xmlattr{name = Name, value = Value}.
+    {Name, Value}.
+
+xmlattr_label(Label) ->
+    xmlattr(<<"label">>, Label).
+
+xmlattr_type(Type) ->
+    xmlattr(<<"type">>, Type).
+
+xmlattr_var(Var) ->
+    xmlattr(<<"var">>, Var).
+
+
+xmlel(NS, Name, Attrs, Children) ->
+    #xmlel{name = Name, attrs = [{<<"xmlns">>, NS} | Attrs], children = Children}.
+
+xmlel(Name, Attrs, Children) ->
+    xmlel(?NS_XDATA, Name, Attrs, Children).
+
+xmlel_desc(CData) ->
+    xmlel(<<"desc">>, [], [xmlcdata(CData)]).
+
+xmlel_value(Value) ->
+    xmlel(<<"value">>, [], [xmlcdata(Value)]).
+
+xmlel_option({Value, Label}) ->
+    xmlel(<<"option">>, [xmlattr_label(Label)], [xmlel_value(Value)]);
+xmlel_option(Value) ->
+    xmlel(<<"option">>, [], [xmlel_value(Value)]).
+
+xmlel_field(Var, Type, Values) ->
+    xmlel(<<"field">>,
+        [xmlattr_var(Var),
+         xmlattr_type(Type)],
+         [xmlel_value(Value) || Value <- Values]).
+
+xmlel_field(Var, Type, Label, Values, Options) ->
+    xmlel(<<"field">>,
+        [xmlattr_var(Var),
+         xmlattr_label(Label),
+         xmlattr_type(Type)],
+         [xmlel_option(Option) || Option <- Options]
+         ++
+         [xmlel_value(Value) || Value <- Values]).
+
+xmlel_field_boolean(Var, Label, Value) ->
+    xmlel_field(Var, <<"boolean">>, Label, [Value], []).
+
+%%
+xmlel_field_fixed(Var, Label, Value) ->
+    xmlel_field(Var, <<"fixed">>, Label, [Value], []).
+
+%%
+xmlel_field_hidden(Var, Value) ->
+    xmlel_field(Var, <<"hidden">>, [Value]).
+
+%%
+xmlel_field_list_single(Var, Label, Value, Options) ->
+    xmlel_field(Var, <<"list-single">>, Label, [Value], Options).
+
+%%
+xmlel_field_list_multi(Var, Label, Values, Options) ->
+    xmlel_field(Var, <<"list-multi">>, Label, Values, Options).
+
+%%
+xmlel_field_text_single(Var, Label, undefined = _Text) ->
+    xmlel_field(Var, <<"text-single">>, Label, [], []);
+%%
+xmlel_field_text_single(Var, Label, Text) ->
+    xmlel_field(Var, <<"text-single">>, Label, [Text], []).
+
+%%
+xmlel_field_text_multi(Var, Label, Values) ->
+    xmlel_field(Var, <<"text-multi">>, Label, Values, []).
+
+%%
+xmlel_field_jid_multi(Var, Label, Jids) ->
+    xmlel_field(Var, <<"jid-multi">>, Label, Jids, []).
+
+%%
+xmlel_field_jid_single(Var, Label, Jid) ->
+    xmlel_field(Var, <<"jid-single">>, Label, [Jid], []).
+
+%%
+xmlel_x(Type, Fields) ->
+   xmlel(<<"x">>, [xmlattr_type(Type)], Fields).
+
+%%
+xmlel_title(Title) ->
+    xmlel(<<"title">>, [], [xmlcdata(Title)]).
+
+%%
+xmlel_instructions(Instructions) when is_list(Instructions) ->
+    lists:map(fun xmlel_instructions/1, Instructions);
+%%
+xmlel_instructions(Instruction) when is_binary(Instruction) ->
+    xmlel(<<"instructions">>, [], [xmlcdata(Instruction)]).