refactor(mgmt_trace): Decorate RPCs

apps/emqx/src/emqx_rpc.erl

@@ -30,6 +30,7 @@
 -export_type([ badrpc/0
              , call_result/0
              , cast_result/0
+             , multicall_result/1
              , multicall_result/0
              , erpc/1
              , erpc_multicall/1
@@ -48,7 +49,9 @@
 
 -type cast_result() :: true.
 
--type multicall_result() :: {_Results :: [term()], _BadNodes :: [node()]}.
+-type multicall_result(Result) :: {[Result], _BadNodes :: [node()]}.
+
+-type multicall_result() :: multicall_result(term()).
 
 -type erpc(Ret) :: {ok, Ret}
                  | {throw, _Err}

apps/emqx/src/emqx_trace/emqx_trace.erl

@@ -204,7 +204,7 @@ get_trace_filename(Name) ->
         end end,
     transaction(Tran).
 
--spec trace_file(File :: list()) ->
+-spec trace_file(File :: file:filename_all()) ->
     {ok, Node :: list(), Binary :: binary()} |
     {error, Node :: list(), Reason :: term()}.
 trace_file(File) ->

apps/emqx_management/src/emqx_mgmt_api_trace.erl

@@ -241,7 +241,7 @@ trace(get, _Params) ->
             List = lists:sort(fun(#{start_at := A}, #{start_at := B}) -> A > B end,
                 emqx_trace:format(List0)),
             Nodes = mria_mnesia:running_nodes(),
-            TraceSize = cluster_call(?MODULE, get_trace_size, [], 30000),
+            TraceSize = wrap_rpc(emqx_mgmt_trace_proto_v1:get_trace_size(Nodes)),
             AllFileSize = lists:foldl(fun(F, Acc) -> maps:merge(Acc, F) end, #{}, TraceSize),
             Now = erlang:system_time(second),
             Traces =
@@ -333,13 +333,12 @@ group_trace_file(ZipDir, TraceLog, TraceFiles) ->
                 end, [], TraceFiles).
 
 collect_trace_file(TraceLog) ->
-    cluster_call(emqx_trace, trace_file, [TraceLog], 60000).
-
-cluster_call(Mod, Fun, Args, Timeout) ->
     Nodes = mria_mnesia:running_nodes(),
-    {GoodRes, BadNodes} = rpc:multicall(Nodes, Mod, Fun, Args, Timeout),
+    wrap_rpc(emqx_mgmt_trace_proto_v1:trace_file(Nodes, TraceLog)).
+
+wrap_rpc({GoodRes, BadNodes}) ->
     BadNodes =/= [] andalso
-        ?SLOG(error, #{msg => "rpc_call_failed", bad_nodes => BadNodes, mfa => {Mod, Fun, Args}}),
+        ?SLOG(error, #{msg => "rpc_call_failed", bad_nodes => BadNodes}),
     GoodRes.
 
 stream_log_file(get, #{bindings := #{name := Name}, query_string := Query}) ->
@@ -348,7 +347,7 @@ stream_log_file(get, #{bindings := #{name := Name}, query_string := Query}) ->
     Bytes = maps:get(<<"bytes">>, Query, 1000),
     case to_node(Node0) of
         {ok, Node} ->
-            case rpc:call(Node, ?MODULE, read_trace_file, [Name, Position, Bytes]) of
+            case emqx_mgmt_trace_proto_v1:read_trace_file(Node, Name, Position, Bytes) of
                 {ok, Bin} ->
                     Meta = #{<<"position">> => Position + byte_size(Bin), <<"bytes">> => Bytes},
                     {200, #{meta => Meta, items => Bin}};
@@ -368,6 +367,7 @@ stream_log_file(get, #{bindings := #{name := Name}, query_string := Query}) ->
         {error, not_found} -> {400, #{code => 'NODE_ERROR', message => <<"Node not found">>}}
     end.
 
+-spec get_trace_size() -> #{{node(), file:name_all()} => non_neg_integer()}.
 get_trace_size() ->
     TraceDir = emqx_trace:trace_dir(),
     Node = node(),
@@ -381,6 +381,12 @@ get_trace_size() ->
     end.
 
 %% this is an rpc call for stream_log_file/2
+-spec read_trace_file( binary()
+                     , non_neg_integer()
+                     , non_neg_integer()
+                     ) -> {ok, binary()}
+                        | {error, _}
+                        | {eof, non_neg_integer()}.
 read_trace_file(Name, Position, Limit) ->
     case emqx_trace:get_trace_filename(Name) of
         {error, _} = Error -> Error;

apps/emqx_management/src/proto/emqx_mgmt_trace_proto_v1.erl

@@ -0,0 +1,51 @@
+%%--------------------------------------------------------------------
+%% 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_mgmt_trace_proto_v1).
+
+-behaviour(emqx_bpapi).
+
+-export([ introduced_in/0
+
+        , trace_file/2
+        , get_trace_size/1
+        , read_trace_file/4
+        ]).
+
+-include_lib("emqx/include/bpapi.hrl").
+
+introduced_in() ->
+    "5.0.0".
+
+-spec get_trace_size([node()]) ->
+          emqx_rpc:multicall_result(#{{node(), file:name_all()} => non_neg_integer()}).
+get_trace_size(Nodes) ->
+    rpc:multicall(Nodes, emqx_mgmt_api_trace, get_trace_size, [], 30000).
+
+-spec trace_file([node()], file:name_all()) ->
+          emqx_rpc:multicall_result(
+            {ok, Node :: list(), Binary :: binary()} |
+            {error, Node :: list(), Reason :: term()}).
+trace_file(Nodes, File) ->
+    rpc:multicall(Nodes, emqx_trace, trace_file, [File], 60000).
+
+-spec read_trace_file(node(), binary(), non_neg_integer(), non_neg_integer()) ->
+                {ok, binary()}
+              | {error, _}
+              | {eof, non_neg_integer()}
+              | {badrpc, _}.
+read_trace_file(Node, Name, Position, Limit) ->
+    rpc:call(Node, emqx_mgmt_api_trace, read_trace_file, [Name, Position, Limit]).