fix(emqx_gateway): Apply remarks

apps/emqx_gateway/src/emqx_gateway_cm.erl

@@ -187,8 +187,12 @@ get_chan_info(GwName, ClientId, ChanPid) ->
           [pid()].
 lookup_by_clientid(GwName, ClientId) ->
     Nodes = mria_mnesia:running_nodes(),
-    Pids = emqx_gateway_cm_proto_v1:lookup_by_clientid(Nodes, GwName, ClientId),
-    lists:append([Pid || {ok, Pid} <- Pids]).
+    case emqx_gateway_cm_proto_v1:lookup_by_clientid(Nodes, GwName, ClientId) of
+        {Pids, []} ->
+            lists:append(Pids);
+        {_, _BadNodes} ->
+            error(badrpc)
+    end.
 
 %% @doc Update infos of the channel.
 -spec set_chan_info(gateway_name(),

apps/emqx_gateway/src/emqx_gateway_http.erl

@@ -244,9 +244,11 @@ lookup_client(GwName, ClientId, {M, F}) ->
 kickout_client(GwName, ClientId) ->
     Results = [emqx_gateway_cm:kick_session(GwName, ClientId, Pid)
                || Pid <- emqx_gateway_cm:lookup_by_clientid(GwName, ClientId)],
-    case Results =:= [] orelse lists:any(fun(Item) -> Item =:= ok end, Results) of
-        true  -> ok;
-        false -> lists:last(Results)
+    IsOk = lists:any(fun(Item) -> Item =:= ok end, Results),
+    case {IsOk, Results} of
+        {true , _ } -> ok;
+        {_    , []} -> {error, not_found};
+        {false, _ } -> lists:last(Results)
     end.
 
 -spec list_client_subscriptions(gateway_name(), emqx_types:clientid())

apps/emqx_gateway/src/proto/emqx_gateway_cm_proto_v1.erl

@@ -38,7 +38,7 @@ introduced_in() ->
 -spec lookup_by_clientid([node()], emqx_gateway_cm:gateway_name(), emqx_types:clientid()) ->
           emqx_rpc:multicall_return([pid()]).
 lookup_by_clientid(Nodes, GwName, ClientId) ->
-    erpc:multicall(Nodes, emqx_gateway_cm, do_lookup_by_clientid, [GwName, ClientId]).
+    rpc:multicall(Nodes, emqx_gateway_cm, do_lookup_by_clientid, [GwName, ClientId]).
 
 -spec get_chan_info(emqx_gateway_cm:gateway_name(), emqx_types:clientid(), pid())
       -> emqx_types:infos() | undefined | {badrpc, _}.

apps/emqx_gateway/test/emqx_gateway_cm_SUITE.erl

@@ -200,6 +200,7 @@ t_kick_session(_) ->
         100 ->
             ?assert(false, "waiting kick msg timeout")
     end,
+    ?assertMatch({error, not_found}, emqx_gateway_http:kickout_client(?GWNAME, <<"i-dont-exist">>)),
     meck:unload(emqx_gateway_cm_registry).
 
 t_unexpected_handle(Conf) ->