refactor: remove the emqx_bridge_monitor module

apps/emqx_bridge/src/emqx_bridge.erl

@@ -17,6 +17,7 @@
 -behaviour(emqx_config_handler).
 -include_lib("emqx/include/emqx.hrl").
 -include_lib("emqx/include/logger.hrl").
+-include_lib("snabbkaffe/include/snabbkaffe.hrl").
 
 -export([post_config_update/5]).
 
@@ -46,6 +47,30 @@
 %% exported for `emqx_telemetry'
 -export([get_basic_usage_info/0]).
 
+load() ->
+    %% set wait_for_resource_ready => 0 to start resources async
+    Opts = #{auto_retry_interval => 60000, wait_for_resource_ready => 0},
+    Bridges = emqx:get_config([bridges], #{}),
+    lists:foreach(
+        fun({Type, NamedConf}) ->
+            lists:foreach(
+                fun({Name, Conf}) ->
+                    _Res = emqx_bridge_resource:create(Type, Name, Conf, Opts),
+                    ?tp(
+                        emqx_bridge_loaded,
+                        #{
+                            type => Type,
+                            name => Name,
+                            res => _Res
+                        }
+                    )
+                end,
+                maps:to_list(NamedConf)
+            )
+        end,
+        maps:to_list(Bridges)
+    ).
+
 load_hook() ->
     Bridges = emqx:get_config([bridges], #{}),
     load_hook(Bridges).
@@ -138,10 +163,6 @@ post_config_update(_, _Req, NewConf, OldConf, _AppEnv) ->
     ok = load_hook(NewConf),
     Result.
 
-load() ->
-    Bridges = emqx:get_config([bridges], #{}),
-    emqx_bridge_monitor:ensure_all_started(Bridges).
-
 list() ->
     lists:foldl(
         fun({Type, NameAndConf}, Bridges) ->

apps/emqx_bridge/src/emqx_bridge_monitor.erl

@@ -1,90 +0,0 @@
-%%--------------------------------------------------------------------
-%% Copyright (c) 2020-2022 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.
-%%--------------------------------------------------------------------
-%% This process monitors all the data bridges, and try to restart a bridge
-%% when one of it stopped.
--module(emqx_bridge_monitor).
-
--behaviour(gen_server).
-
--include_lib("snabbkaffe/include/snabbkaffe.hrl").
-
-%% API functions
--export([
-    start_link/0,
-    ensure_all_started/1
-]).
-
-%% gen_server callbacks
--export([
-    init/1,
-    handle_call/3,
-    handle_cast/2,
-    handle_info/2,
-    terminate/2,
-    code_change/3
-]).
-
--record(state, {}).
-
-start_link() ->
-    gen_server:start_link({local, ?MODULE}, ?MODULE, [], []).
-
-ensure_all_started(Configs) ->
-    gen_server:cast(?MODULE, {start_and_monitor, Configs}).
-
-init([]) ->
-    {ok, #state{}}.
-
-handle_call(_Request, _From, State) ->
-    Reply = ok,
-    {reply, Reply, State}.
-
-handle_cast({start_and_monitor, Configs}, State) ->
-    ok = load_bridges(Configs),
-    {noreply, State};
-handle_cast(_Msg, State) ->
-    {noreply, State}.
-
-handle_info(_Info, State) ->
-    {noreply, State}.
-
-terminate(_Reason, _State) ->
-    ok.
-
-code_change(_OldVsn, State, _Extra) ->
-    {ok, State}.
-
-%%============================================================================
-load_bridges(Configs) ->
-    lists:foreach(
-        fun({Type, NamedConf}) ->
-            lists:foreach(
-                fun({Name, Conf}) ->
-                    _Res = emqx_bridge_resource:create(Type, Name, Conf),
-                    ?tp(
-                        emqx_bridge_monitor_loaded_bridge,
-                        #{
-                            type => Type,
-                            name => Name,
-                            res => _Res
-                        }
-                    )
-                end,
-                maps:to_list(NamedConf)
-            )
-        end,
-        maps:to_list(Configs)
-    ).

apps/emqx_bridge/src/emqx_bridge_resource.erl

@@ -28,6 +28,7 @@
 -export([
     create/2,
     create/3,
+    create/4,
     recreate/2,
     recreate/3,
     create_dry_run/2,
@@ -79,6 +80,9 @@ create(BridgeId, Conf) ->
     create(BridgeType, BridgeName, Conf).
 
 create(Type, Name, Conf) ->
+    create(Type, Name, Conf, #{auto_retry_interval => 60000}).
+
+create(Type, Name, Conf, Opts) ->
     ?SLOG(info, #{
         msg => "create bridge",
         type => Type,
@@ -90,7 +94,7 @@ create(Type, Name, Conf) ->
         <<"emqx_bridge">>,
         bridge_to_resource_type(Type),
         parse_confs(Type, Name, Conf),
-        #{auto_retry_interval => 60000}
+        Opts
     ),
     maybe_disable_bridge(Type, Name, Conf).
 
@@ -132,13 +136,14 @@ update(Type, Name, {OldConf, Conf}) ->
         true ->
             %% we don't need to recreate the bridge if this config change is only to
             %% toggole the config 'bridge.{type}.{name}.enable'
+            _ =
                 case maps:get(enable, Conf, true) of
                     true ->
-                    _ = restart(Type, Name),
+                        restart(Type, Name);
-                    ok;
                     false ->
                         stop(Type, Name)
-            end
+                end,
+            ok
     end.
 
 recreate(Type, Name) ->

apps/emqx_bridge/src/emqx_bridge_sup.erl

@@ -32,15 +32,7 @@ init([]) ->
         intensity => 10,
         period => 10
     },
-    ChildSpecs = [
+    ChildSpecs = [],
-        #{
-            id => emqx_bridge_monitor,
-            start => {emqx_bridge_monitor, start_link, []},
-            restart => permanent,
-            type => worker,
-            modules => [emqx_bridge_monitor]
-        }
-    ],
     {ok, {SupFlags, ChildSpecs}}.
 
 %% internal functions

apps/emqx_bridge/test/emqx_bridge_SUITE.erl

@@ -147,7 +147,7 @@ setup_fake_telemetry_data() ->
     ok = emqx_common_test_helpers:load_config(emqx_bridge_schema, Conf, Opts),
 
     ok = snabbkaffe:start_trace(),
-    Predicate = fun(#{?snk_kind := K}) -> K =:= emqx_bridge_monitor_loaded_bridge end,
+    Predicate = fun(#{?snk_kind := K}) -> K =:= emqx_bridge_loaded end,
     NEvents = 3,
     BackInTime = 0,
     Timeout = 11_000,