Keep last handled stanzas number in cache rather than session table

rebar.config

@@ -20,7 +20,7 @@
 
 {deps, [{lager, ".*", {git, "https://github.com/erlang-lager/lager", "3.6.7"}},
         {p1_utils, ".*", {git, "https://github.com/processone/p1_utils", {tag, "1.0.13"}}},
-        {cache_tab, ".*", {git, "https://github.com/processone/cache_tab", {tag, "1.0.16"}}},
+        {cache_tab, ".*", {git, "https://github.com/processone/cache_tab", {tag, "6493974"}}},
         {fast_tls, ".*", {git, "https://github.com/processone/fast_tls", {tag, "1.0.26"}}},
         {stringprep, ".*", {git, "https://github.com/processone/stringprep", {tag, "1.0.14"}}},
         {fast_xml, ".*", {git, "https://github.com/processone/fast_xml", {tag, "1.1.34"}}},

src/ejabberd_sm.erl

@@ -50,8 +50,6 @@
 	 set_presence/7,
 	 unset_presence/6,
 	 close_session_unset_presence/5,
-	 set_offline_info/5,
-	 get_offline_info/4,
 	 dirty_get_sessions_list/0,
 	 dirty_get_my_sessions_list/0,
 	 get_vh_session_list/1,
@@ -78,8 +76,7 @@
 	 host_down/1,
 	 make_sid/0,
 	 clean_cache/1,
-	 config_reloaded/0,
+	 config_reloaded/0
-	 is_online/1
 	]).
 
 -export([init/1, handle_call/3, handle_cast/2,
@@ -211,14 +208,14 @@ get_user_resources(User, Server) ->
     LUser = jid:nodeprep(User),
     LServer = jid:nameprep(Server),
     Mod = get_sm_backend(LServer),
-    Ss = online(get_sessions(Mod, LUser, LServer)),
+    Ss = get_sessions(Mod, LUser, LServer),
     [element(3, S#session.usr) || S <- clean_session_list(Ss)].
 
 -spec get_user_present_resources(binary(), binary()) -> [tuple()].
 
 get_user_present_resources(LUser, LServer) ->
     Mod = get_sm_backend(LServer),
-    Ss = online(get_sessions(Mod, LUser, LServer)),
+    Ss = get_sessions(Mod, LUser, LServer),
     [{S#session.priority, element(3, S#session.usr)}
      || S <- clean_session_list(Ss), is_integer(S#session.priority)].
 
@@ -229,7 +226,7 @@ get_user_ip(User, Server, Resource) ->
     LServer = jid:nameprep(Server),
     LResource = jid:resourceprep(Resource),
     Mod = get_sm_backend(LServer),
-    case online(get_sessions(Mod, LUser, LServer, LResource)) of
+    case get_sessions(Mod, LUser, LServer, LResource) of
 	[] ->
 	    undefined;
 	Ss ->
@@ -242,7 +239,7 @@ get_user_info(User, Server) ->
     LUser = jid:nodeprep(User),
     LServer = jid:nameprep(Server),
     Mod = get_sm_backend(LServer),
-    Ss = online(get_sessions(Mod, LUser, LServer)),
+    Ss = get_sessions(Mod, LUser, LServer),
     [{LResource, [{node, node(Pid)}, {ts, Ts}, {pid, Pid},
 		  {priority, Priority} | Info]}
      || #session{usr = {_, _, LResource},
@@ -257,7 +254,7 @@ get_user_info(User, Server, Resource) ->
     LServer = jid:nameprep(Server),
     LResource = jid:resourceprep(Resource),
     Mod = get_sm_backend(LServer),
-    case online(get_sessions(Mod, LUser, LServer, LResource)) of
+    case get_sessions(Mod, LUser, LServer, LResource) of
 	[] ->
 	    offline;
 	Ss ->
@@ -316,7 +313,7 @@ get_session_sid(User, Server, Resource) ->
     LServer = jid:nameprep(Server),
     LResource = jid:resourceprep(Resource),
     Mod = get_sm_backend(LServer),
-    case online(get_sessions(Mod, LUser, LServer, LResource)) of
+    case get_sessions(Mod, LUser, LServer, LResource) of
 	[] ->
 	    none;
 	Ss ->
@@ -330,43 +327,15 @@ get_session_sids(User, Server) ->
     LUser = jid:nodeprep(User),
     LServer = jid:nameprep(Server),
     Mod = get_sm_backend(LServer),
-    Sessions = online(get_sessions(Mod, LUser, LServer)),
+    Sessions = get_sessions(Mod, LUser, LServer),
     [SID || #session{sid = SID} <- Sessions].
 
--spec set_offline_info(sid(), binary(), binary(), binary(), info()) -> ok.
-
-set_offline_info(SID, User, Server, Resource, Info) ->
-    LUser = jid:nodeprep(User),
-    LServer = jid:nameprep(Server),
-    LResource = jid:resourceprep(Resource),
-    set_session(SID, LUser, LServer, LResource, undefined, [offline | Info]).
-
--spec get_offline_info(erlang:timestamp(), binary(), binary(),
-                       binary()) -> none | info().
-
-get_offline_info(Time, User, Server, Resource) ->
-    LUser = jid:nodeprep(User),
-    LServer = jid:nameprep(Server),
-    LResource = jid:resourceprep(Resource),
-    Mod = get_sm_backend(LServer),
-    case get_sessions(Mod, LUser, LServer, LResource) of
-	[#session{sid = {Time, _}, info = Info}] ->
-	    case proplists:get_bool(offline, Info) of
-		true ->
-		    Info;
-		false ->
-		    none
-	    end;
-	_ ->
-	    none
-    end.
-
 -spec dirty_get_sessions_list() -> [ljid()].
 
 dirty_get_sessions_list() ->
     lists:flatmap(
       fun(Mod) ->
-	      [S#session.usr || S <- online(get_sessions(Mod))]
+	      [S#session.usr || S <- get_sessions(Mod)]
       end, get_sm_backends()).
 
 -spec dirty_get_my_sessions_list() -> [#session{}].
@@ -374,7 +343,7 @@ dirty_get_sessions_list() ->
 dirty_get_my_sessions_list() ->
     lists:flatmap(
       fun(Mod) ->
-	      [S || S <- online(get_sessions(Mod)),
+	      [S || S <- get_sessions(Mod),
 		    node(element(2, S#session.sid)) == node()]
       end, get_sm_backends()).
 
@@ -383,14 +352,14 @@ dirty_get_my_sessions_list() ->
 get_vh_session_list(Server) ->
     LServer = jid:nameprep(Server),
     Mod = get_sm_backend(LServer),
-    [S#session.usr || S <- online(get_sessions(Mod, LServer))].
+    [S#session.usr || S <- get_sessions(Mod, LServer)].
 
 -spec get_all_pids() -> [pid()].
 
 get_all_pids() ->
     lists:flatmap(
       fun(Mod) ->
-	      [element(2, S#session.sid) || S <- online(get_sessions(Mod))]
+	      [element(2, S#session.sid) || S <- get_sessions(Mod)]
       end, get_sm_backends()).
 
 -spec get_vh_session_number(binary()) -> non_neg_integer().
@@ -398,7 +367,7 @@ get_all_pids() ->
 get_vh_session_number(Server) ->
     LServer = jid:nameprep(Server),
     Mod = get_sm_backend(LServer),
-    length(online(get_sessions(Mod, LServer))).
+    length(get_sessions(Mod, LServer)).
 
 %% Why the hell do we have so many similar kicks?
 c2s_handle_info(#{lang := Lang} = State, replaced) ->
@@ -579,16 +548,6 @@ delete_session(Mod, #session{usr = {LUser, LServer, _}} = Session) ->
 	    ok
     end.
 
--spec online([#session{}]) -> [#session{}].
-
-online(Sessions) ->
-    lists:filter(fun is_online/1, Sessions).
-
--spec is_online(#session{}) -> boolean().
-
-is_online(#session{info = Info}) ->
-    not proplists:get_bool(offline, Info).
-
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 -spec do_route(jid(), term()) -> any().
 do_route(#jid{lresource = <<"">>} = To, Term) ->
@@ -600,7 +559,7 @@ do_route(To, Term) ->
     ?DEBUG("broadcasting ~p to ~s", [Term, jid:encode(To)]),
     {U, S, R} = jid:tolower(To),
     Mod = get_sm_backend(S),
-    case online(get_sessions(Mod, U, S, R)) of
+    case get_sessions(Mod, U, S, R) of
 	[] ->
 	    ?DEBUG("dropping broadcast to unavailable resourse: ~p", [Term]);
 	Ss ->
@@ -631,7 +590,7 @@ do_route(#presence{to = To, type = T} = Packet)
 		      ejabberd_c2s:route(Pid, {route, Packet1});
 		 (_) ->
 		      ok
-	      end, online(get_sessions(Mod, LUser, LServer)));
+	      end, get_sessions(Mod, LUser, LServer));
 	false ->
 	    ok
     end;
@@ -660,7 +619,7 @@ do_route(Packet) ->
     To = xmpp:get_to(Packet),
     {LUser, LServer, LResource} = jid:tolower(To),
     Mod = get_sm_backend(LServer),
-    case online(get_sessions(Mod, LUser, LServer, LResource)) of
+    case get_sessions(Mod, LUser, LServer, LResource) of
 	[] ->
 	    case Packet of
 		#message{type = T} when T == chat; T == normal ->
@@ -708,8 +667,8 @@ route_message(#message{to = To, type = Type} = Packet) ->
 					  (P >= 0) and (Type == headline) ->
 				LResource = jid:resourceprep(R),
 				Mod = get_sm_backend(LServer),
-				case online(get_sessions(Mod, LUser, LServer,
+				case get_sessions(Mod, LUser, LServer,
-							     LResource)) of
+						  LResource) of
 				  [] ->
 				      ok; % Race condition
 				  Ss ->
@@ -780,13 +739,9 @@ check_for_sessions_to_replace(User, Server, Resource) ->
 check_existing_resources(LUser, LServer, LResource) ->
     Mod = get_sm_backend(LServer),
     Ss = get_sessions(Mod, LUser, LServer, LResource),
-    {OnlineSs, OfflineSs} = lists:partition(fun is_online/1, Ss),
+    if Ss == [] -> ok;
-    lists:foreach(fun(S) ->
-			  delete_session(Mod, S)
-		  end, OfflineSs),
-    if OnlineSs == [] -> ok;
        true ->
-	   SIDs = [SID || #session{sid = SID} <- OnlineSs],
+	   SIDs = [SID || #session{sid = SID} <- Ss],
 	   MaxSID = lists:max(SIDs),
 	   lists:foreach(fun ({_, Pid} = S) when S /= MaxSID ->
 				 ejabberd_c2s:route(Pid, replaced);
@@ -806,22 +761,17 @@ get_resource_sessions(User, Server, Resource) ->
     LServer = jid:nameprep(Server),
     LResource = jid:resourceprep(Resource),
     Mod = get_sm_backend(LServer),
-    [S#session.sid || S <- online(get_sessions(Mod, LUser, LServer, LResource))].
+    [S#session.sid || S <- get_sessions(Mod, LUser, LServer, LResource)].
 
 -spec check_max_sessions(binary(), binary()) -> ok | replaced.
 check_max_sessions(LUser, LServer) ->
     Mod = get_sm_backend(LServer),
     Ss = get_sessions(Mod, LUser, LServer),
-    {OnlineSs, OfflineSs} = lists:partition(fun is_online/1, Ss),
     MaxSessions = get_max_user_sessions(LUser, LServer),
-    if length(OnlineSs) =< MaxSessions -> ok;
+    if length(Ss) =< MaxSessions -> ok;
        true ->
-	    #session{sid = {_, Pid}} = lists:min(OnlineSs),
+	    #session{sid = {_, Pid}} = lists:min(Ss),
 	    ejabberd_c2s:route(Pid, replaced)
-    end,
-    if length(OfflineSs) =< MaxSessions -> ok;
-       true ->
-	    delete_session(Mod, lists:min(OfflineSs))
     end.
 
 %% Get the user_max_session setting
@@ -843,7 +793,7 @@ get_max_user_sessions(LUser, Host) ->
 
 force_update_presence({LUser, LServer}) ->
     Mod = get_sm_backend(LServer),
-    Ss = online(get_sessions(Mod, LUser, LServer)),
+    Ss = get_sessions(Mod, LUser, LServer),
     lists:foreach(fun (#session{sid = {_, Pid}}) ->
 			  ejabberd_c2s:resend_presence(Pid)
 		  end,

src/mod_stream_mgmt.erl

@@ -40,6 +40,8 @@
 -include("logger.hrl").
 -include("p1_queue.hrl").
 
+-define(STREAM_MGMT_CACHE, stream_mgmt_cache).
+
 -define(is_sm_packet(Pkt),
 	is_record(Pkt, sm_enable) or
 	is_record(Pkt, sm_resume) or
@@ -51,7 +53,8 @@
 %%%===================================================================
 %%% API
 %%%===================================================================
-start(Host, _Opts) ->
+start(Host, Opts) ->
+    init_cache(Opts),
     ejabberd_hooks:add(c2s_init, ?MODULE, c2s_stream_init, 50),
     ejabberd_hooks:add(c2s_stream_started, Host, ?MODULE,
 		       c2s_stream_started, 50),
@@ -284,23 +287,16 @@ c2s_terminated(#{mgmt_state := resumed, jid := JID} = State, _Reason) ->
 	   [jid:encode(JID)]),
     bounce_message_queue(),
     {stop, State};
-c2s_terminated(#{mgmt_state := MgmtState, mgmt_stanzas_in := In, sid := SID,
+c2s_terminated(#{mgmt_state := MgmtState, mgmt_stanzas_in := In,
-		 user := U, server := S, resource := R} = State, Reason) ->
+		 sid := {Time, _}, jid := JID} = State, _Reason) ->
-    Result = case MgmtState of
+    case MgmtState of
 	timeout ->
-		     Info = [{num_stanzas_in, In}],
+	    store_stanzas_in(jid:tolower(JID), Time, In);
-		     %% TODO: Usually, ejabberd_c2s:process_terminated/2 is
-		     %% called later in the hook chain.  We swap the order so
-		     %% that the offline info won't be purged after we stored
-		     %% it.  This should be fixed in a proper way.
-		     State1 = ejabberd_c2s:process_terminated(State, Reason),
-		     ejabberd_sm:set_offline_info(SID, U, S, R, Info),
-		     {stop, State1};
 	_ ->
-		     State
+	    ok
     end,
     route_unacked_stanzas(State),
-    Result;
+    State;
 c2s_terminated(State, _Reason) ->
     State.
 
@@ -641,16 +637,11 @@ inherit_session_state(#{user := U, server := S,
 	{term, {R, Time}} ->
 	    case ejabberd_sm:get_session_pid(U, S, R) of
 		none ->
-		    case ejabberd_sm:get_offline_info(Time, U, S, R) of
+		    case pop_stanzas_in({U, S, R}, Time) of
-			none ->
+			error ->
 			    {error, <<"Previous session PID not found">>};
-			Info ->
+			{ok, H} ->
-			    case proplists:get_value(num_stanzas_in, Info) of
-				undefined ->
-				    {error, <<"Previous session timed out">>};
-				H ->
 			    {error, <<"Previous session timed out">>, H}
-			    end
 		    end;
 		OldPID ->
 		    OldSID = {Time, OldPID},
@@ -750,6 +741,32 @@ need_to_enqueue(#{mgmt_force_enqueue := true} = State, #xmlel{}) ->
 need_to_enqueue(State, _) ->
     {false, State}.
 
+%%%===================================================================
+%%% Cache-like storage for last handled stanzas
+%%%===================================================================
+init_cache(Opts) ->
+    ets_cache:new(?STREAM_MGMT_CACHE, cache_opts(Opts)).
+
+cache_opts(Opts) ->
+    [{max_size, gen_mod:get_opt(cache_size, Opts)},
+     {life_time, infinity}].
+
+-spec store_stanzas_in(ljid(), erlang:timestamp(), non_neg_integer()) -> boolean().
+store_stanzas_in(LJID, Time, Num) ->
+    ets_cache:insert(?STREAM_MGMT_CACHE, {LJID, Time}, Num,
+		     ejabberd_cluster:get_nodes()).
+
+-spec pop_stanzas_in(ljid(), erlang:timestamp()) -> {ok, non_neg_integer()} | error.
+pop_stanzas_in(LJID, Time) ->
+    case ets_cache:lookup(?STREAM_MGMT_CACHE, {LJID, Time}) of
+	{ok, Val} ->
+	    ets_cache:delete(?STREAM_MGMT_CACHE, {LJID, Time},
+			     ejabberd_cluster:get_nodes()),
+	    {ok, Val};
+	error ->
+	    error
+    end.
+
 %%%===================================================================
 %%% Configuration processing
 %%%===================================================================
@@ -796,6 +813,11 @@ mod_opt_type(resend_on_timeout) ->
     fun(B) when is_boolean(B) -> B;
        (if_offline) -> if_offline
     end;
+mod_opt_type(cache_size) ->
+    fun(I) when is_integer(I), I>0 -> I;
+       (unlimited) -> infinity;
+       (infinity) -> infinity
+    end;
 mod_opt_type(queue_type) ->
     fun(ram) -> ram; (file) -> file end.
 
@@ -804,5 +826,6 @@ mod_options(Host) ->
      {resume_timeout, 300},
      {max_resume_timeout, undefined},
      {ack_timeout, 60},
+     {cache_size, ejabberd_config:cache_size(Host)},
      {resend_on_timeout, false},
      {queue_type, ejabberd_config:default_queue_type(Host)}].