feat: refactored some bridges to avoid leaking resources during crashes at creation

apps/emqx_bridge_mqtt/src/emqx_bridge_mqtt_connector.erl

@@ -83,6 +83,7 @@ start_ingress(ResourceId, Ingress, ClientOpts) ->
         {ingress, Ingress},
         {client_opts, ClientOpts}
     ],
+    ok = emqx_resource:allocate_resource(ResourceId, ingress_pool_name, PoolName),
     case emqx_resource_pool:start(PoolName, emqx_bridge_mqtt_ingress, Options) of
         ok ->
             {ok, #{ingress_pool_name => PoolName}};
@@ -132,6 +133,7 @@ start_egress(ResourceId, Egress, ClientOpts) ->
         {pool_size, PoolSize},
         {client_opts, ClientOpts}
     ],
+    ok = emqx_resource:allocate_resource(ResourceId, egress_pool_name, PoolName),
     case emqx_resource_pool:start(PoolName, emqx_bridge_mqtt_egress, Options) of
         ok ->
             {ok, #{
@@ -142,13 +144,14 @@ start_egress(ResourceId, Egress, ClientOpts) ->
             {error, Reason}
     end.
 
-on_stop(ResourceId, State) ->
+on_stop(ResourceId, _State) ->
     ?SLOG(info, #{
         msg => "stopping_mqtt_connector",
         connector => ResourceId
     }),
-    ok = stop_ingress(State),
+    Allocated = emqx_resource:get_allocated_resources(ResourceId),
-    ok = stop_egress(State).
+    ok = stop_ingress(Allocated),
+    ok = stop_egress(Allocated).
 
 stop_ingress(#{ingress_pool_name := PoolName}) ->
     emqx_resource_pool:stop(PoolName);

apps/emqx_bridge_tdengine/src/emqx_bridge_tdengine_connector.erl

@@ -108,6 +108,7 @@ on_start(
 
     Prepares = parse_prepare_sql(Config),
     State = Prepares#{pool_name => InstanceId, query_opts => query_opts(Config)},
+    ok = emqx_resource:allocate_resource(InstanceId, pool_name, InstanceId),
     case emqx_resource_pool:start(InstanceId, ?MODULE, Options) of
         ok ->
             {ok, State};
@@ -115,12 +116,17 @@ on_start(
             Error
     end.
 
-on_stop(InstanceId, #{pool_name := PoolName}) ->
+on_stop(InstanceId, _State) ->
     ?SLOG(info, #{
         msg => "stopping_tdengine_connector",
         connector => InstanceId
     }),
-    emqx_resource_pool:stop(PoolName).
+    case emqx_resource:get_allocated_resources(InstanceId) of
+        #{pool_name := PoolName} ->
+            emqx_resource_pool:stop(PoolName);
+        _ ->
+            ok
+    end.
 
 on_query(InstanceId, {query, SQL}, State) ->
     do_query(InstanceId, SQL, State);

apps/emqx_connector/src/emqx_connector_http.erl

@@ -219,18 +219,24 @@ on_start(
         base_path => BasePath,
         request => preprocess_request(maps:get(request, Config, undefined))
     },
+    ok = emqx_resource:allocate_resource(InstId, pool_name, InstId),
     case ehttpc_sup:start_pool(InstId, PoolOpts) of
         {ok, _} -> {ok, State};
         {error, {already_started, _}} -> {ok, State};
         {error, Reason} -> {error, Reason}
     end.
 
-on_stop(InstId, #{pool_name := PoolName}) ->
+on_stop(InstId, _State) ->
     ?SLOG(info, #{
         msg => "stopping_http_connector",
         connector => InstId
     }),
-    ehttpc_sup:stop_pool(PoolName).
+    case emqx_resource:get_allocated_resources(InstId) of
+        #{pool_name := PoolName} ->
+            ehttpc_sup:stop_pool(PoolName);
+        _ ->
+            ok
+    end.
 
 on_query(InstId, {send_message, Msg}, State) ->
     case maps:get(request, State, undefined) of

apps/emqx_connector/src/emqx_connector_ldap.erl

@@ -97,17 +97,23 @@ on_start(
         {pool_size, PoolSize},
         {auto_reconnect, ?AUTO_RECONNECT_INTERVAL}
     ],
+    ok = emqx_resource:allocate_resource(InstId, pool_name, InstId),
     case emqx_resource_pool:start(InstId, ?MODULE, Opts ++ SslOpts) of
         ok -> {ok, #{pool_name => InstId}};
         {error, Reason} -> {error, Reason}
     end.
 
-on_stop(InstId, #{pool_name := PoolName}) ->
+on_stop(InstId, _State) ->
     ?SLOG(info, #{
         msg => "stopping_ldap_connector",
         connector => InstId
     }),
-    emqx_resource_pool:stop(PoolName).
+    case emqx_resource:get_allocated_resources(InstId) of
+        #{pool_name := PoolName} ->
+            emqx_resource_pool:stop(PoolName);
+        _ ->
+            ok
+    end.
 
 on_query(InstId, {search, Base, Filter, Attributes}, #{pool_name := PoolName} = State) ->
     Request = {Base, Filter, Attributes},

apps/emqx_connector/src/emqx_connector_mongo.erl

@@ -183,6 +183,7 @@ on_start(
         {worker_options, init_worker_options(maps:to_list(NConfig), SslOpts)}
     ],
     Collection = maps:get(collection, Config, <<"mqtt">>),
+    ok = emqx_resource:allocate_resource(InstId, pool_name, InstId),
     case emqx_resource_pool:start(InstId, ?MODULE, Opts) of
         ok ->
             {ok, #{
@@ -194,12 +195,17 @@ on_start(
             {error, Reason}
     end.
 
-on_stop(InstId, #{pool_name := PoolName}) ->
+on_stop(InstId, _State) ->
     ?SLOG(info, #{
         msg => "stopping_mongodb_connector",
         connector => InstId
     }),
-    emqx_resource_pool:stop(PoolName).
+    case emqx_resource:get_allocated_resources(InstId) of
+        #{pool_name := PoolName} ->
+            emqx_resource_pool:stop(PoolName);
+        _ ->
+            ok
+    end.
 
 on_query(
     InstId,

apps/emqx_connector/src/emqx_connector_mysql.erl

@@ -124,6 +124,7 @@ on_start(
             ]
         ),
     State = parse_prepare_sql(Config),
+    ok = emqx_resource:allocate_resource(InstId, pool_name, InstId),
     case emqx_resource_pool:start(InstId, ?MODULE, Options ++ SslOpts) of
         ok ->
             {ok, init_prepare(State#{pool_name => InstId})};
@@ -140,12 +141,17 @@ maybe_add_password_opt(undefined, Options) ->
 maybe_add_password_opt(Password, Options) ->
     [{password, Password} | Options].
 
-on_stop(InstId, #{pool_name := PoolName}) ->
+on_stop(InstId, _State) ->
     ?SLOG(info, #{
         msg => "stopping_mysql_connector",
         connector => InstId
     }),
-    emqx_resource_pool:stop(PoolName).
+    case emqx_resource:get_allocated_resources(InstId) of
+        #{pool_name := PoolName} ->
+            emqx_resource_pool:stop(PoolName);
+        _ ->
+            ok
+    end.
 
 on_query(InstId, {TypeOrKey, SQLOrKey}, State) ->
     on_query(InstId, {TypeOrKey, SQLOrKey, [], default_timeout}, State);

apps/emqx_connector/src/emqx_connector_pgsql.erl

@@ -121,6 +121,7 @@ on_start(
         {pool_size, PoolSize}
     ],
     State = parse_prepare_sql(Config),
+    ok = emqx_resource:allocate_resource(InstId, pool_name, InstId),
     case emqx_resource_pool:start(InstId, ?MODULE, Options ++ SslOpts) of
         ok ->
             {ok, init_prepare(State#{pool_name => InstId, prepare_statement => #{}})};
@@ -132,12 +133,17 @@ on_start(
             {error, Reason}
     end.
 
-on_stop(InstId, #{pool_name := PoolName}) ->
+on_stop(InstId, _State) ->
     ?SLOG(info, #{
         msg => "stopping postgresql connector",
         connector => InstId
     }),
-    emqx_resource_pool:stop(PoolName).
+    case emqx_resource:get_allocated_resources(InstId) of
+        #{pool_name := PoolName} ->
+            emqx_resource_pool:stop(PoolName);
+        _ ->
+            ok
+    end.
 
 on_query(InstId, {TypeOrKey, NameOrSQL}, State) ->
     on_query(InstId, {TypeOrKey, NameOrSQL, []}, State);

apps/emqx_connector/src/emqx_connector_redis.erl

@@ -160,6 +160,8 @@ on_start(
                 [{ssl, false}]
         end ++ [{sentinel, maps:get(sentinel, Config, undefined)}],
     State = #{pool_name => InstId, type => Type},
+    ok = emqx_resource:allocate_resource(InstId, type, Type),
+    ok = emqx_resource:allocate_resource(InstId, pool_name, InstId),
     case Type of
         cluster ->
             case eredis_cluster:start_pool(InstId, Opts ++ [{options, Options}]) of
@@ -177,14 +179,18 @@ on_start(
             end
     end.
 
-on_stop(InstId, #{pool_name := PoolName, type := Type}) ->
+on_stop(InstId, _State) ->
     ?SLOG(info, #{
         msg => "stopping_redis_connector",
         connector => InstId
     }),
-    case Type of
+    case emqx_resource:get_allocated_resources(InstId) of
-        cluster -> eredis_cluster:stop_pool(PoolName);
+        #{pool_name := PoolName, type := cluster} ->
-        _ -> emqx_resource_pool:stop(PoolName)
+            eredis_cluster:stop_pool(PoolName);
+        #{pool_name := PoolName, type := _} ->
+            emqx_resource_pool:stop(PoolName);
+        _ ->
+            ok
     end.
 
 on_query(InstId, {cmd, _} = Query, State) ->