feat(gw-sn): call subscribe/unsubscribe hook

apps/emqx_gateway/src/mqttsn/emqx_sn_channel.erl

@@ -845,19 +845,31 @@ check_subscribe_authz({_TopicId, TopicName, _QoS},
 
 do_subscribe({TopicId, TopicName, QoS},
              Channel = #channel{
+                          ctx = Ctx,
                           session = Session,
                           clientinfo = ClientInfo
                                      = #{mountpoint := Mountpoint}}) ->
-    NTopicName = emqx_mountpoint:mount(Mountpoint, TopicName),
-    SubOpts = maps:merge(?DEFAULT_SUBOPTS, #{qos => QoS}),
-    case emqx_session:subscribe(ClientInfo, NTopicName, SubOpts, Session) of
-        {ok, NSession} ->
-            {ok, {TopicId, QoS},
-             Channel#channel{session = NSession}};
-        {error, ?RC_QUOTA_EXCEEDED} ->
-            ?LOG(warning, "Cannot subscribe ~s due to ~s.",
-                 [TopicName, emqx_reason_codes:text(?RC_QUOTA_EXCEEDED)]),
-            {error, ?SN_EXCEED_LIMITATION}
+
+    {TopicName1, SubOpts0} = emqx_topic:parse(TopicName),
+    TopicFilters = [{TopicName1, SubOpts0#{qos => QoS}}],
+    case run_hooks(Ctx, 'client.subscribe',
+                   [ClientInfo, #{}], TopicFilters) of
+        [] ->
+            ?LOG(warning, "Skip to subscribe ~s, "
+                          "due to 'client.subscribe' denied!", [TopicName]),
+            {ok, Channel};
+        [{NTopicName, NSubOpts}|_] ->
+            NTopicName1 = emqx_mountpoint:mount(Mountpoint, NTopicName),
+            NSubOpts1 = maps:merge(?DEFAULT_SUBOPTS, NSubOpts),
+            case emqx_session:subscribe(ClientInfo, NTopicName1, NSubOpts1, Session) of
+                {ok, NSession} ->
+                    {ok, {TopicId, QoS},
+                     Channel#channel{session = NSession}};
+                {error, ?RC_QUOTA_EXCEEDED} ->
+                    ?LOG(warning, "Cannot subscribe ~s due to ~s.",
+                         [TopicName, emqx_reason_codes:text(?RC_QUOTA_EXCEEDED)]),
+                    {error, ?SN_EXCEED_LIMITATION}
+            end
     end.
 
 %%--------------------------------------------------------------------
@@ -891,16 +903,29 @@ preproc_unsub_type(?SN_UNSUBSCRIBE_MSG_TYPE(?SN_SHORT_TOPIC,
 
 do_unsubscribe(TopicName,
                Channel = #channel{
+                            ctx = Ctx,
                             session = Session,
                             clientinfo = ClientInfo
                                        = #{mountpoint := Mountpoint}}) ->
-    NTopicName = emqx_mountpoint:mount(Mountpoint, TopicName),
-    case emqx_session:unsubscribe(ClientInfo, NTopicName,
-                                  ?DEFAULT_SUBOPTS, Session) of
-        {ok, NSession} ->
-            {ok, Channel#channel{session = NSession}};
-        {error, ?RC_NO_SUBSCRIPTION_EXISTED} ->
-            {ok, Channel}
+    TopicFilters = [emqx_topic:parse(TopicName)],
+    case run_hooks(Ctx, 'client.unsubscribe',
+                   [ClientInfo, #{}], TopicFilters) of
+        [] ->
+            %% Skip to unsubscribe
+            {ok, Channel};
+        [{NTopicName, NSubOpts}|_] ->
+            NTopicName1 = emqx_mountpoint:mount(Mountpoint, NTopicName),
+            NSubOpts1 = maps:merge(
+                          emqx_gateway_utils:default_subopts(),
+                          NSubOpts
+                         ),
+            case emqx_session:unsubscribe(ClientInfo, NTopicName1,
+                                          NSubOpts1, Session) of
+                {ok, NSession} ->
+                    {ok, Channel#channel{session = NSession}};
+                {error, ?RC_NO_SUBSCRIPTION_EXISTED} ->
+                    {ok, Channel}
+            end
     end.
 
 %%--------------------------------------------------------------------

apps/emqx_gateway/src/mqttsn/emqx_sn_registry.erl

@@ -155,7 +155,8 @@ init([InstaId, PredefTopics]) ->
     % FIXME:
     %ok = ekka_rlog:wait_for_shards([?CM_SHARD], infinity),
     MaxPredefId = lists:foldl(
-                    fun(#{id := TopicId, topic := TopicName}, AccId) ->
+                    fun(#{id := TopicId, topic := TopicName0}, AccId) ->
+                        TopicName = iolist_to_binary(TopicName0),
                         ekka_mnesia:dirty_write(Tab, #emqx_sn_registry{
                                                         key = {predef, TopicId},
                                                         value = TopicName}