contributors

README.md

@@ -102,12 +102,12 @@ The MIT License (MIT)
 
 ## Contributors
 
-[@hejin1026](https://github.com/hejin1026)
-[@desoulter](https://github.com/desoulter)
-[@turtleDeng](https://github.com/turtleDeng)
-[@Hades32](https://github.com/Hades32)
-[@huangdan](https://github.com/huangdan)
-[@callbay](https://github.com/callbay)
+* [@hejin1026](https://github.com/hejin1026)
+* [@desoulter](https://github.com/desoulter)
+* [@turtleDeng](https://github.com/turtleDeng)
+* [@Hades32](https://github.com/Hades32)
+* [@huangdan](https://github.com/huangdan)
+* [@callbay](https://github.com/callbay)
 
 
 ## Author

apps/emqttd/src/emqttd_session.erl

@@ -173,17 +173,31 @@ puback(SessPid, {?PUBCOMP, PacketId}) when is_pid(SessPid) ->
 %%------------------------------------------------------------------------------
 -spec subscribe(session(), [{binary(), mqtt_qos()}]) -> {ok, session(), [mqtt_qos()]}.
 subscribe(SessState = #session_state{clientid = ClientId, submap = SubMap}, Topics) ->
-    Resubs = [Topic || {Name, _Qos} = Topic <- Topics, maps:is_key(Name, SubMap)], 
-    case Resubs of
-        [] -> ok;
-        _  -> lager:warning("~s resubscribe ~p", [ClientId, Resubs])
-    end,
-    SubMap1 = lists:foldl(fun({Name, Qos}, Acc) -> maps:put(Name, Qos, Acc) end, SubMap, Topics),
+
+    %% subscribe first and don't care if the subscriptions have been existed
     {ok, GrantedQos} = emqttd_pubsub:subscribe(Topics),
+
     lager:info([{client, ClientId}], "Client ~s subscribe ~p. Granted QoS: ~p",
-                    [ClientId, Topics, GrantedQos]),
-    %%TODO: should be gen_event and notification...
-    [emqttd_msg_store:redeliver(Name, self()) || {Name, _} <- Topics],
+                   [ClientId, Topics, GrantedQos]),
+
+
+    %% <MQTT V3.1.1>: 3.8.4
+    %% Where the Topic Filter is not identical to any existing Subscription’s filter,
+    %% a new Subscription is created and all matching retained messages are sent.
+    lists:foreach(fun({Name, _Qos}) ->
+          case maps:is_key(Name, SubMap) of
+          true ->
+              lager:warning("~s resubscribe ~p", [ClientId, Name]);
+          false ->
+              %%TODO: this is not right, rewrite later...
+              emqttd_msg_store:redeliver(Name, self())
+          end
+    end, Topics),
+
+    SubMap1 = lists:foldl(fun({Name, Qos}, Acc) ->
+                                  maps:put(Name, Qos, Acc)
+                          end, SubMap, Topics),
+
     {ok, SessState#session_state{submap = SubMap1}, GrantedQos};
 
 subscribe(SessPid, Topics) when is_pid(SessPid) ->