refactor(emqx): Decorate remote procedure calls

apps/emqx/src/emqx.erl

@@ -86,7 +86,7 @@ stop() ->
 %% @doc Is emqx running?
 -spec(is_running(node()) -> boolean()).
 is_running(Node) ->
-    case rpc:call(Node, ?MODULE, is_running, []) of
+    case emqx_proto_v1:is_running(Node) of
         {badrpc, _}          -> false;
         Result               -> Result
     end.

apps/emqx/src/proto/emqx_proto_v1.erl

@@ -0,0 +1,32 @@
+%%--------------------------------------------------------------------
+%% Copyright (c) 2022 EMQ Technologies Co., Ltd. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%--------------------------------------------------------------------
+
+-module(emqx_proto_v1).
+
+-behaviour(emqx_bpapi).
+
+-include("bpapi.hrl").
+
+-export([ introduced_in/0
+        , is_running/1
+        ]).
+
+introduced_in() ->
+    "5.0.0".
+
+-spec is_running(node()) -> boolean() | {badrpc, term()}.
+is_running(Node) ->
+    rpc:call(Node, emqx, is_running, []).