Support XEP-0357: Push Notifications

Closes #1379.

1 files changed, 204 insertions, 0 deletions

diff --git a/src/mod_push_mnesia.erl b/src/mod_push_mnesia.erl
new file mode 100644
index 00000000..04ea8d60
--- /dev/null
+++ b/src/mod_push_mnesia.erl
@@ -0,0 +1,204 @@
+%%%----------------------------------------------------------------------
+%%% File    : mod_push_mnesia.erl
+%%% Author  : Holger Weiss <holger@zedat.fu-berlin.de>
+%%% Purpose : Mnesia backend for Push Notifications (XEP-0357)
+%%% Created : 15 Jul 2017 by Holger Weiss <holger@zedat.fu-berlin.de>
+%%%
+%%%
+%%% ejabberd, Copyright (C) 2017   ProcessOne
+%%%
+%%% This program is free software; you can redistribute it and/or
+%%% modify it under the terms of the GNU General Public License as
+%%% published by the Free Software Foundation; either version 2 of the
+%%% License, or (at your option) any later version.
+%%%
+%%% This program is distributed in the hope that it will be useful,
+%%% but WITHOUT ANY WARRANTY; without even the implied warranty of
+%%% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+%%% General Public License for more details.
+%%%
+%%% You should have received a copy of the GNU General Public License along
+%%% with this program; if not, write to the Free Software Foundation, Inc.,
+%%% 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+%%%
+%%%----------------------------------------------------------------------
+
+-module(mod_push_mnesia).
+-author('holger@zedat.fu-berlin.de').
+
+-behavior(mod_push).
+
+%% API
+-export([init/2, store_session/6, lookup_session/4, lookup_session/3,
+	 lookup_sessions/3, lookup_sessions/2, lookup_sessions/1,
+	 delete_session/3, delete_old_sessions/2]).
+
+-include_lib("stdlib/include/ms_transform.hrl").
+-include("logger.hrl").
+-include("xmpp.hrl").
+
+-record(push_session,
+	{us = {<<"">>, <<"">>}                  :: {binary(), binary()},
+	 timestamp = p1_time_compat:timestamp() :: erlang:timestamp(),
+	 service = {<<"">>, <<"">>, <<"">>}     :: ljid(),
+	 node = <<"">>                          :: binary(),
+	 xdata = #xdata{}                       :: xdata()}).
+
+%%%-------------------------------------------------------------------
+%%% API
+%%%-------------------------------------------------------------------
+init(_Host, _Opts) ->
+    ejabberd_mnesia:create(?MODULE, push_session,
+			   [{disc_only_copies, [node()]},
+			    {type, bag},
+			    {attributes, record_info(fields, push_session)}]).
+
+store_session(LUser, LServer, TS, PushJID, Node, XData) ->
+    US = {LUser, LServer},
+    PushLJID = jid:tolower(PushJID),
+    MaxSessions = ejabberd_sm:get_max_user_sessions(LUser, LServer),
+    F = fun() ->
+		if is_integer(MaxSessions) ->
+			enforce_max_sessions(US, MaxSessions - 1);
+		   MaxSessions == infinity ->
+			ok
+		end,
+		mnesia:write(#push_session{us = US,
+					   timestamp = TS,
+					   service = PushLJID,
+					   node = Node,
+					   xdata = XData})
+	end,
+    case mnesia:transaction(F) of
+	{atomic, ok} ->
+	    {ok, {TS, PushLJID, Node, XData}};
+	{aborted, E} ->
+	    ?ERROR_MSG("Cannot store push session for ~s@~s: ~p",
+		       [LUser, LServer, E]),
+	    error
+    end.
+
+lookup_session(LUser, LServer, PushJID, Node) ->
+    PushLJID = jid:tolower(PushJID),
+    MatchSpec = ets:fun2ms(
+		  fun(#push_session{us = {U, S}, service = P, node = N} = Rec)
+			when U == LUser,
+			     S == LServer,
+			     P == PushLJID,
+			     N == Node ->
+			  Rec
+		  end),
+    case mnesia:dirty_select(push_session, MatchSpec) of
+	[#push_session{timestamp = TS, xdata = XData}] ->
+	    {ok, {TS, PushLJID, Node, XData}};
+	_ ->
+	    ?DEBUG("No push session found for ~s@~s (~p, ~s)",
+		   [LUser, LServer, PushJID, Node]),
+	    error
+    end.
+
+lookup_session(LUser, LServer, TS) ->
+    MatchSpec = ets:fun2ms(
+		  fun(#push_session{us = {U, S}, timestamp = T} = Rec)
+			when U == LUser,
+			     S == LServer,
+			     T == TS ->
+			  Rec
+		  end),
+    case mnesia:dirty_select(push_session, MatchSpec) of
+	[#push_session{service = PushLJID, node = Node, xdata = XData}] ->
+	    {ok, {TS, PushLJID, Node, XData}};
+	_ ->
+	    ?DEBUG("No push session found for ~s@~s (~p)",
+		   [LUser, LServer, TS]),
+	    error
+    end.
+
+lookup_sessions(LUser, LServer, PushJID) ->
+    PushLJID = jid:tolower(PushJID),
+    MatchSpec = ets:fun2ms(
+		  fun(#push_session{us = {U, S}, service = P, node = N} = Rec)
+			when U == LUser,
+			     S == LServer,
+			     P == PushLJID ->
+			  Rec
+		  end),
+    {ok, mnesia:dirty_select(push_session, MatchSpec)}.
+
+lookup_sessions(LUser, LServer) ->
+    Records = mnesia:dirty_read(push_session, {LUser, LServer}),
+    Clients = [{TS, PushLJID, Node, XData}
+	       || #push_session{timestamp = TS,
+				service = PushLJID,
+				node = Node,
+				xdata = XData} <- Records],
+    {ok, Clients}.
+
+lookup_sessions(LServer) ->
+    MatchSpec = ets:fun2ms(
+		  fun(#push_session{us = {_U, S},
+				    timestamp = TS,
+				    service = PushLJID,
+				    node = Node,
+				    xdata = XData})
+			when S == LServer ->
+			  {TS, PushLJID, Node, XData}
+		  end),
+    {ok, mnesia:dirty_select(push_session, MatchSpec)}.
+
+delete_session(LUser, LServer, TS) ->
+    MatchSpec = ets:fun2ms(
+		  fun(#push_session{us = {U, S}, timestamp = T} = Rec)
+			when U == LUser,
+			     S == LServer,
+			     T == TS ->
+			  Rec
+		  end),
+    F = fun() ->
+		Recs = mnesia:select(push_session, MatchSpec),
+		lists:foreach(fun mnesia:delete_object/1, Recs)
+	end,
+    case mnesia:transaction(F) of
+	{atomic, ok} ->
+	    ok;
+	{aborted, E} ->
+	    ?ERROR_MSG("Cannot delete push seesion of ~s@~s: ~p",
+		       [LUser, LServer, E]),
+	    error
+    end.
+
+delete_old_sessions(_LServer, Time) ->
+    DelIfOld = fun(#push_session{timestamp = T} = Rec, ok) when T < Time ->
+		       mnesia:delete_object(Rec);
+		  (_Rec, ok) ->
+		       ok
+	       end,
+    F = fun() ->
+		mnesia:foldl(DelIfOld, ok, push_session)
+	end,
+    case mnesia:transaction(F) of
+	{atomic, ok} ->
+	    ok;
+	{aborted, E} ->
+	    ?ERROR_MSG("Cannot delete old push sessions: ~p", [E]),
+	    error
+    end.
+
+%%--------------------------------------------------------------------
+%% Internal functions.
+%%--------------------------------------------------------------------
+-spec enforce_max_sessions({binary(), binary()}, non_neg_integer()) -> ok.
+enforce_max_sessions({U, S} = US, Max) ->
+    Recs = mnesia:wread({push_session, US}),
+    NumRecs = length(Recs),
+    if NumRecs > Max ->
+	    NumOldRecs = NumRecs - Max,
+	    Recs1 = lists:keysort(#push_session.timestamp, Recs),
+	    Recs2 = lists:reverse(Recs1),
+	    OldRecs = lists:sublist(Recs2, Max + 1, NumOldRecs),
+	    ?INFO_MSG("Disabling ~B old push session(s) of ~s@~s",
+		      [NumOldRecs, U, S]),
+	    lists:foreach(fun(Rec) -> mnesia:delete_object(Rec) end, OldRecs);
+       true ->
+	    ok
+    end.