experimental patch including XEP-248 (thanks to Brian Cully)

SVN Revision: 2157

1 files changed, 246 insertions, 0 deletions

diff --git a/src/mod_pubsub/nodetree_dag.erl b/src/mod_pubsub/nodetree_dag.erl
new file mode 100644
index 00000000..1a5921fb
--- /dev/null
+++ b/src/mod_pubsub/nodetree_dag.erl
@@ -0,0 +1,246 @@
+%%% ====================================================================
+%%% ``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.
+%%%
+%%% @author Brian Cully <bjc@kublai.com>
+%%% @version {@vsn}, {@date} {@time}
+%%% @end
+%%% ====================================================================
+
+-module(nodetree_dag).
+-author('bjc@kublai.com').
+
+%% API
+-export([init/3,
+	 terminate/2,
+	 options/0,
+	 set_node/1,
+	 get_node/3,
+	 get_node/2,
+	 get_node/1,
+	 get_nodes/2,
+	 get_nodes/1,
+	 get_parentnodes/3,
+	 get_parentnodes_tree/3,
+	 get_subnodes/3,
+	 get_subnodes_tree/3,
+	 create_node/5,
+	 delete_node/2]).
+
+-include_lib("stdlib/include/qlc.hrl").
+
+-include("ejabberd.hrl").
+-include("pubsub.hrl").
+-include("jlib.hrl").
+
+-behaviour(gen_pubsub_nodetree).
+
+-define(DEFAULT_NODETYPE, leaf).
+-define(DEFAULT_PARENTS, []).
+-define(DEFAULT_CHILDREN, []).
+
+-compile(export_all).
+
+%%====================================================================
+%% API
+%%====================================================================
+init(Host, ServerHost, Opts) ->
+    nodetree_tree:init(Host, ServerHost, Opts),
+    mnesia:transaction(fun create_node/5,
+		       [Host, [], "default", service_jid(ServerHost), []]).
+
+terminate(Host, ServerHost) ->
+    nodetree_tree:terminate(Host, ServerHost).
+
+create_node(Key, NodeID, Type, Owner, Options) ->
+    OwnerJID = jlib:jid_tolower(jlib:jid_remove_resource(Owner)),
+    case find_node(Key, NodeID) of
+	false ->
+	    ID = pubsub_index:new(node),
+	    N = #pubsub_node{nodeid = oid(Key, NodeID),
+			     id = ID,
+			     type = Type,
+			     owners = [OwnerJID],
+			     options = Options},
+	    case set_node(N) of
+		ok    -> {ok, ID};
+		Other -> Other
+	    end;
+	_ ->
+	    {error, ?ERR_CONFLICT}
+    end.
+
+set_node(#pubsub_node{nodeid  = {Key, _},
+		      owners  = Owners,
+		      options = Options} = Node) ->
+    Parents = find_opt(collection, ?DEFAULT_PARENTS,  Options),
+    case validate_parentage(Key, Owners, Parents) of
+	true ->
+	    %% Update parents whenever the config changes.
+	    mnesia:write(Node#pubsub_node{parents = Parents});
+	Other ->
+	    Other
+    end.
+
+delete_node(Key, NodeID) ->
+    case find_node(Key, NodeID) of
+	false ->
+	    {error, ?ERR_ITEM_NOT_FOUND};
+	Node ->
+	    %% Find all of N's children, update their configs to
+	    %% remove N from the collection setting.
+	    lists:foreach(fun (#pubsub_node{options = Opts} = Child) ->
+				  NewOpts = remove_config_parent(NodeID, Opts),
+				  Parents = find_opt(collection, ?DEFAULT_PARENTS, NewOpts),
+				  ok = mnesia:write(pubsub_node,
+						    Child#pubsub_node{
+						      parents = Parents,
+						      options = NewOpts},
+						    write)
+			  end, get_subnodes(Key, NodeID)),
+
+	    %% Remove and return the requested node.
+	    mnesia:delete_object(pubsub_node, Node, write),
+	    [Node]
+    end.
+
+options() ->
+    nodetree_tree:options().
+
+get_node(Host, NodeID, _From) ->
+    get_node(Host, NodeID).
+
+get_node(Host, NodeID) ->
+    case find_node(Host, NodeID) of
+	false -> {error, ?ERR_ITEM_NOT_FOUND};
+	Node  -> Node
+    end.
+
+get_node(NodeId) ->
+    nodetree_tree:get_node(NodeId).
+
+get_nodes(Key, From) ->
+    nodetree_tree:get_nodes(Key, From).
+
+get_nodes(Key) ->
+    nodetree_tree:get_nodes(Key).
+
+get_parentnodes(Host, NodeID, _From) ->
+    case find_node(Host, NodeID) of
+	false -> {error, ?ERR_ITEM_NOT_FOUND};
+	#pubsub_node{parents = Parents} ->
+	    Q = qlc:q([N || #pubsub_node{nodeid = {NHost, NNode}} = N <- mnesia:table(pubsub_node),
+			    Parent <- Parents,
+			    Host == NHost,
+			    Parent == NNode]),
+	    qlc:e(Q)
+    end.
+
+get_parentnodes_tree(Host, NodeID, _From) ->
+    Pred = fun (NID, #pubsub_node{nodeid = {_, NNodeID}}) ->
+		   NID == NNodeID
+	   end,
+    Tr = fun (#pubsub_node{parents = Parents}) -> Parents end,
+    traversal_helper(Pred, Tr, Host, [NodeID]).
+
+get_subnodes(Host, NodeID, _From) ->
+    get_subnodes(Host, NodeID).
+
+get_subnodes(Host, NodeID) ->
+    case find_node(Host, NodeID) of
+	false -> {error, ?ERR_ITEM_NOT_FOUND};
+	_ ->
+	    Q = qlc:q([Node || #pubsub_node{nodeid  = {NHost, _},
+					    parents = Parents} = Node <- mnesia:table(pubsub_node),
+			       Host == NHost,
+			       lists:member(NodeID, Parents)]),
+	    qlc:e(Q)
+    end.
+
+get_subnodes_tree(Host, NodeID, _From) ->
+    Pred = fun (NID, #pubsub_node{parents = Parents}) ->
+		   lists:member(NID, Parents)
+	   end,
+    Tr = fun (#pubsub_node{nodeid = {_, N}}) -> N end,
+    traversal_helper(Pred, Tr, Host, [NodeID]).
+
+%%====================================================================
+%% Internal functions
+%%====================================================================
+oid(Key, Name) -> {Key, Name}.
+
+%% Key    = jlib:jid() | host()
+%% NodeID = string()
+find_node(Key, NodeID) ->
+    case mnesia:read(pubsub_node, oid(Key, NodeID), read) of
+	[]     -> false;
+	[Node] -> Node
+    end.
+
+%% Key     = jlib:jid() | host()
+%% Default = term()
+%% Options = [{Key = atom(), Value = term()}]
+find_opt(Key, Default, Options) ->
+    case lists:keysearch(Key, 1, Options) of
+	{value, {Key, Val}} -> Val;
+	_		   -> Default
+    end.
+
+traversal_helper(Pred, Tr, Host, NodeIDs) ->
+    traversal_helper(Pred, Tr, 0, Host, NodeIDs, []).
+
+traversal_helper(_Pred, _Tr, _Depth, _Host, [], Acc) ->
+    Acc;
+traversal_helper(Pred, Tr, Depth, Host, NodeIDs, Acc) ->
+    Q = qlc:q([Node || #pubsub_node{nodeid = {NHost, _}} = Node <- mnesia:table(pubsub_node),
+		       NodeID <- NodeIDs,
+		       Host   == NHost,
+		       Pred(NodeID, Node)]),
+    Nodes = qlc:e(Q),
+    IDs = lists:flatmap(Tr, Nodes),
+    traversal_helper(Pred, Tr, Depth + 1, Host, IDs, [{Depth, Nodes} | Acc]).
+
+remove_config_parent(NodeID, Options) ->
+    remove_config_parent(NodeID, Options, []).
+
+remove_config_parent(_NodeID, [], Acc) ->
+    lists:reverse(Acc);
+remove_config_parent(NodeID, [{collection, Parents} | T], Acc) ->
+    remove_config_parent(NodeID, T,
+			 [{collection, lists:delete(NodeID, Parents)} | Acc]);
+remove_config_parent(NodeID, [H | T], Acc) ->
+    remove_config_parent(NodeID, T, [H | Acc]).
+
+validate_parentage(_Key, _Owners, []) ->
+    true;
+validate_parentage(Key, Owners, [[] | T]) ->
+    validate_parentage(Key, Owners, T);
+validate_parentage(Key, Owners, [ParentID | T]) ->
+    case find_node(Key, ParentID) of
+	false -> {error, ?ERR_ITEM_NOT_FOUND};
+	#pubsub_node{owners = POwners, options = POptions} ->
+	    NodeType = find_opt(node_type, ?DEFAULT_NODETYPE, POptions),
+	    MutualOwners = [O || O <- Owners, PO <- POwners,
+				 O == PO],
+	    case {MutualOwners, NodeType} of
+		{[], _}	 -> {error, ?ERR_NOT_ALLOWED};
+		{_, collection} -> validate_parentage(Key, Owners, T)
+	    end
+    end.
+
+%% @spec (Host) -> jid()
+%%	Host = host()
+%% @doc <p>Generate pubsub service JID.</p>
+service_jid(Host) ->
+    case Host of
+	{U,S,_} -> {jid, U, S, "", U, S, ""};
+	_       -> {jid, "", Host, "", "", Host, ""}
+    end.