test(exhook): ExHook message hooks with topic filters

apps/emqx_exhook/test/emqx_exhook_SUITE.erl

@@ -27,6 +27,12 @@
 -define(OTHER_CLUSTER_NAME_ATOM, test_emqx_cluster).
 -define(OTHER_CLUSTER_NAME_STRING, "test_emqx_cluster").
 
+-define(TEST_PUBLISH_FILTERS_ATOM, test_message_filters).
+-define(TEST_PUBLISH_FILTERS_STRING, "test_message_filters").
+
+-define(BEFORE, <<"before_hardcoded">>).
+-define(AFTER, <<"after_hardcoded">>).
+
 %%--------------------------------------------------------------------
 %% Setups
 %%--------------------------------------------------------------------
@@ -136,6 +142,50 @@ t_cluster_name(_) ->
     [Callback | _] = emqx_hooks:lookup('client.connected'),
     ?assertEqual(1, emqx_hooks:callback_priority(Callback)).
 
+t_message_topic_filters(_) ->
+    %% ========== Prepare hooks
+    Priority = 2,
+    SetEnvFun =
+        fun(emqx) ->
+                set_special_cfgs(emqx),
+                application:set_env(ekka, cluster_name, ?TEST_PUBLISH_FILTERS_ATOM);
+           (emqx_exhook) ->
+                application:set_env(emqx_exhook, hook_priority, Priority)
+        end,
+
+    emqx_ct_helpers:stop_apps([emqx, emqx_exhook]),
+    emqx_ct_helpers:start_apps([emqx, emqx_exhook], SetEnvFun),
+
+    ?assertEqual(?TEST_PUBLISH_FILTERS_STRING, emqx_sys:cluster_name()),
+
+    emqx_exhook:disable(default),
+    ok = emqx_exhook:enable(default),
+    %% See emqx_exhook_demo_svr:on_provider_loaded/2
+
+    [Callback | _] = emqx_hooks:lookup('message.publish'),
+    ?assertEqual(Priority, emqx_hooks:callback_priority(Callback)),
+
+    %% ========== Test topic filters
+    {ok, C1} = emqtt:start_link([{clientid, <<"client1">>}, {username, <<"gooduser">>}]), {ok, _} = emqtt:connect(C1),
+    {ok, C2} = emqtt:start_link([{clientid, <<"test_filter_client">>}, {username, <<"gooduser">>}]), {ok, _} = emqtt:connect(C2),
+
+    {ok, _, _} = emqtt:subscribe(C1,[{<<"t/1">>, qos0}, {<<"t/2">>, qos0}]),
+
+    ok = emqtt:publish(C2, <<"t/1">>, ?BEFORE, 0),
+    [Msg1 | _] = receive_messages(1),
+    ct:pal("~p", [Msg1]),
+    %% server only handle topic `t/1`, rewrite topic `t/1` => `t/2`, rewrite payload hardcoded.
+    ?assertEqual({ok, ?AFTER}, maps:find(payload, Msg1)),
+
+    ok = emqtt:publish(C2, <<"t/2">>, ?BEFORE, 0),
+    [Msg2 | _] = receive_messages(1),
+    ct:pal("~p", [Msg2]),
+    %% `t/2` not matched, no gRPC call, no handled
+    ?assertEqual({ok, ?BEFORE}, maps:find(payload, Msg2)),
+
+    ok = emqtt:disconnect(C1),
+    ok = emqtt:disconnect(C2).
+
 %%--------------------------------------------------------------------
 %% Utils
 %%--------------------------------------------------------------------
@@ -170,3 +220,18 @@ meck_print() ->
 
 unmeck_print() ->
     meck:unload(emqx_ctl).
+
+receive_messages(Count) ->
+    receive_messages(Count, []).
+
+receive_messages(0, Msgs) ->
+    Msgs;
+receive_messages(Count, Msgs) ->
+    receive
+        {publish, Msg} ->
+            receive_messages(Count-1, [Msg|Msgs]);
+        _Other ->
+            receive_messages(Count, Msgs)
+    after 1000 ->
+        Msgs
+    end.

apps/emqx_exhook/test/emqx_exhook_demo_svr.erl

@@ -53,6 +53,8 @@
 -define(NAME, ?MODULE).
 -define(DEFAULT_CLUSTER_NAME, <<"emqxcl">>).
 -define(OTHER_CLUSTER_NAME_BIN, <<"test_emqx_cluster">>).
+-define(TEST_PUBLISH_FILTERS_BIN, <<"test_message_filters">>).
+-define(AFTER_HARDCODED_PAYLOAD, <<"after_hardcoded">>).
 
 %%--------------------------------------------------------------------
 %% Server APIs
@@ -134,16 +136,21 @@ on_provider_loaded(#{meta := #{cluster_name := Name}} = Req, Md) ->
          #{name => <<"session.discarded">>},
          #{name => <<"session.takeovered">>},
          #{name => <<"session.terminated">>}],
+    PublishWithFilter =
+        [#{name => <<"message.publish">>, topics => [<<"t/1">>]}],
+    PublishWithOutFilter =
+        [#{name => <<"message.publish">>}],
     HooksMessage =
-        [#{name => <<"message.publish">>},
-         #{name => <<"message.delivered">>},
+        [#{name => <<"message.delivered">>},
          #{name => <<"message.acked">>},
          #{name => <<"message.dropped">>}],
     case Name of
         ?DEFAULT_CLUSTER_NAME ->
-            {ok, #{hooks => HooksClient ++ HooksSession ++ HooksMessage}, Md};
+            {ok, #{hooks => HooksClient ++ HooksSession ++ PublishWithOutFilter ++ HooksMessage}, Md};
         ?OTHER_CLUSTER_NAME_BIN ->
-            {ok, #{hooks => HooksClient}, Md}
+            {ok, #{hooks => HooksClient}, Md};
+        ?TEST_PUBLISH_FILTERS_BIN ->
+            {ok, #{hooks => HooksClient ++ HooksSession ++ PublishWithFilter ++ HooksMessage}, Md}
     end.
 -spec on_provider_unloaded(emqx_exhook_pb:provider_unloaded_request(), grpc:metadata())
     -> {ok, emqx_exhook_pb:empty_success(), grpc:metadata()}
@@ -319,6 +326,12 @@ on_message_publish(#{message := #{from := From} = Msg} = Req, Md) ->
                         payload => From},
             {ok, #{type => 'STOP_AND_RETURN',
                    value => {message, NMsg}}, Md};
+        <<"test_filter_client">> ->
+            %% rewrite topic and payload
+            NMsg = Msg#{topic => <<"t/2">>,
+                        payload => ?AFTER_HARDCODED_PAYLOAD},
+            {ok, #{type => 'STOP_AND_RETURN',
+                   value => {message, NMsg}}, Md};
         _ ->
             {ok, #{type => 'IGNORE'}, Md}
     end.