refactor(bridge): change confs for channel from array to map

apps/emqx_bridge/etc/emqx_bridge.conf

@@ -25,25 +25,23 @@
 #        certfile = "{{ platform_etc_dir }}/certs/client-cert.pem"
 #        cacertfile = "{{ platform_etc_dir }}/certs/cacert.pem"
 #    }
-#    ## we will create one MQTT connection for each element of the `ingress_channels`
-#    ingress_channels: [{
-#        ## the `id` will be used as part of the clientid
-#        id = "pull_msgs_from_aws"
+#    ## We will create one MQTT connection for each element of the `ingress_channels`
+#    ## Syntax: ingress_channels.<id>
+#    ingress_channels.pull_msgs_from_aws {
 #        subscribe_remote_topic = "aws/#"
 #        subscribe_qos = 1
 #        local_topic = "from_aws/${topic}"
 #        payload = "${payload}"
 #        qos = "${qos}"
 #        retain = "${retain}"
-#    }]
-#    ## we will create one MQTT connection for each element of the `egress_channels`
-#    egress_channels: [{
-#        ## the `id` will be used as part of the clientid
-#        id = "push_msgs_to_aws"
+#    }
+#    ## We will create one MQTT connection for each element of the `egress_channels`
+#    ## Syntax: egress_channels.<id>
+#    egress_channels.push_msgs_to_aws {
 #        subscribe_local_topic = "emqx/#"
 #        remote_topic = "from_emqx/${topic}"
 #        payload = "${payload}"
 #        qos = 1
 #        retain = false
-#    }]
+#    }
 #}

apps/emqx_bridge/src/emqx_bridge_schema.erl

@@ -5,9 +5,9 @@
 %%======================================================================================
 %% Hocon Schema Definitions
 
-roots() -> ["bridges"].
+roots() -> [bridges].
 
-fields("bridges") ->
+fields(bridges) ->
     [{mqtt, hoconsc:mk(hoconsc:map(name, hoconsc:ref(?MODULE, "mqtt_bridge")))}];
 
 fields("mqtt_bridge") ->

apps/emqx_connector/src/emqx_connector_mqtt.erl

@@ -88,20 +88,20 @@ on_start(InstId, Conf) ->
     logger:info("starting mqtt connector: ~p, ~p", [InstId, Conf]),
     NamePrefix = binary_to_list(InstId),
     BasicConf = basic_config(Conf),
-    InitRes = {ok, #{name_prefix => NamePrefix, baisc_conf => BasicConf, sub_bridges => []}},
-    InOutConfigs = check_channel_id_dup(maps:get(ingress_channels, Conf, [])
-                                        ++ maps:get(egress_channels, Conf, [])),
+    InitRes = {ok, #{name_prefix => NamePrefix, baisc_conf => BasicConf, channels => []}},
+    InOutConfigs = taged_map_list(ingress_channels, maps:get(ingress_channels, Conf, #{}))
+                ++ taged_map_list(egress_channels, maps:get(egress_channels, Conf, #{})),
     lists:foldl(fun
             (_InOutConf, {error, Reason}) ->
                 {error, Reason};
-            (InOutConf, {ok, #{sub_bridges := SubBridges} = Res}) ->
+            (InOutConf, {ok, #{channels := SubBridges} = Res}) ->
                 case create_channel(InOutConf, NamePrefix, BasicConf) of
                     {error, Reason} -> {error, Reason};
-                    {ok, Name} -> {ok, Res#{sub_bridges => [Name | SubBridges]}}
+                    {ok, Name} -> {ok, Res#{channels => [Name | SubBridges]}}
                 end
         end, InitRes, InOutConfigs).
 
-on_stop(InstId, #{sub_bridges := NameList}) ->
+on_stop(InstId, #{channels := NameList}) ->
     logger:info("stopping mqtt connector: ~p", [InstId]),
     lists:foreach(fun(Name) ->
             remove_channel(Name)
@@ -117,63 +117,53 @@ on_query(InstId, {publish_to_local, Msg}, _AfterQuery, _State) ->
 on_query(InstId, {publish_to_remote, Msg}, _AfterQuery, _State) ->
     logger:debug("publish to remote node, connector: ~p, msg: ~p", [InstId, Msg]).
 
-on_health_check(_InstId, #{sub_bridges := NameList} = State) ->
+on_health_check(_InstId, #{channels := NameList} = State) ->
     Results = [{Name, emqx_connector_mqtt_worker:ping(Name)} || Name <- NameList],
     case lists:all(fun({_, pong}) -> true; ({_, _}) -> false end, Results) of
         true -> {ok, State};
-        false -> {error, {some_sub_bridge_down, Results}, State}
+        false -> {error, {some_channel_down, Results}, State}
     end.
 
-check_channel_id_dup(Confs) ->
-    lists:foreach(fun(#{id := Id}) ->
-            case length([Id || #{id := Id0} <- Confs, Id0 == Id]) of
-                1 -> ok;
-                L when L > 1 -> error({mqtt_bridge_conf, {duplicate_id_found, Id}})
-            end
-        end, Confs),
-    Confs.
-
-%% this is an `ingress_channels` bridge
-create_channel(#{subscribe_remote_topic := RemoteT, local_topic := LocalT, id := Id} = InConf,
-        NamePrefix, BasicConf) ->
-    Name = bridge_name(NamePrefix, Id),
+create_channel({{ingress_channels, Id}, #{subscribe_remote_topic := RemoteT,
+        local_topic := LocalT} = Conf}, NamePrefix, BasicConf) ->
+    Name = ingress_channel_name(NamePrefix, Id),
     logger:info("creating ingress channel ~p, remote ~s -> local ~s",
         [Name, RemoteT, LocalT]),
-    create_sub_bridge(BasicConf#{
+    do_create_channel(BasicConf#{
         name => Name,
-        clientid => clientid(Id),
-        subscriptions => InConf, forwards => undefined});
-%% this is an `egress_channels` bridge
-create_channel(#{subscribe_local_topic := LocalT, remote_topic := RemoteT, id := Id} = OutConf,
-        NamePrefix, BasicConf) ->
-    Name = bridge_name(NamePrefix, Id),
+        clientid => clientid(Name),
+        subscriptions => Conf, forwards => undefined});
+
+create_channel({{egress_channels, Id}, #{subscribe_local_topic := LocalT,
+        remote_topic := RemoteT} = Conf}, NamePrefix, BasicConf) ->
+    Name = egress_channel_name(NamePrefix, Id),
     logger:info("creating egress channel ~p, local ~s -> remote ~s",
         [Name, LocalT, RemoteT]),
-    create_sub_bridge(BasicConf#{
-        name => bridge_name(NamePrefix, Id),
-        clientid => clientid(Id),
-        subscriptions => undefined, forwards => OutConf}).
-
-remove_channel(BridgeName) ->
-    logger:info("removing channel ~p", [BridgeName]),
-    case ?MODULE:drop_bridge(BridgeName) of
+    do_create_channel(BasicConf#{
+        name => Name,
+        clientid => clientid(Name),
+        subscriptions => undefined, forwards => Conf}).
+
+remove_channel(ChannelName) ->
+    logger:info("removing channel ~p", [ChannelName]),
+    case ?MODULE:drop_bridge(ChannelName) of
         ok -> ok;
         {error, not_found} -> ok;
         {error, Reason} ->
-            logger:error("stop channel ~p failed, error: ~p", [BridgeName, Reason])
+            logger:error("stop channel ~p failed, error: ~p", [ChannelName, Reason])
     end.
 
-create_sub_bridge(#{name := Name} = Conf) ->
+do_create_channel(#{name := Name} = Conf) ->
     case ?MODULE:create_bridge(Conf) of
         {ok, _Pid} ->
-            start_sub_bridge(Name);
+            start_channel(Name);
         {error, {already_started, _Pid}} ->
             {ok, Name};
         {error, Reason} ->
             {error, Reason}
     end.
 
-start_sub_bridge(Name) ->
+start_channel(Name) ->
     case emqx_connector_mqtt_worker:ensure_started(Name) of
         ok -> {ok, Name};
         {error, Reason} -> {error, Reason}
@@ -210,11 +200,19 @@ basic_config(#{
         if_record_metrics => true
     }.
 
-bridge_name(Prefix, Id) ->
-    list_to_atom(str(Prefix) ++ ":" ++ str(Id)).
+taged_map_list(Tag, Map) ->
+    [{{Tag, K}, V} || {K, V} <- maps:to_list(Map)].
+
+ingress_channel_name(Prefix, Id) ->
+    channel_name("ingress_channels", Prefix, Id).
+egress_channel_name(Prefix, Id) ->
+    channel_name("egress_channels", Prefix, Id).
+
+channel_name(Type, Prefix, Id) ->
+    list_to_atom(str(Prefix) ++ ":" ++ Type ++ ":" ++ str(Id)).
 
 clientid(Id) ->
-    list_to_binary(str(Id) ++ ":" ++ emqx_misc:gen_id(16)).
+    list_to_binary(str(Id) ++ ":" ++ emqx_misc:gen_id(8)).
 
 str(A) when is_atom(A) ->
     atom_to_list(A);

apps/emqx_connector/src/mqtt/emqx_connector_mqtt_schema.erl

@@ -38,8 +38,8 @@ fields("config") ->
     , {retry_interval, hoconsc:mk(emqx_schema:duration_ms(), #{default => "30s"})}
     , {max_inflight, hoconsc:mk(integer(), #{default => 32})}
     , {replayq, hoconsc:mk(hoconsc:ref(?MODULE, "replayq"))}
-    , {ingress_channels, hoconsc:mk(hoconsc:array(hoconsc:ref(?MODULE, "ingress_channels")), #{default => []})}
-    , {egress_channels, hoconsc:mk(hoconsc:array(hoconsc:ref(?MODULE, "egress_channels")), #{default => []})}
+    , {ingress_channels, hoconsc:mk(hoconsc:map(id, hoconsc:ref(?MODULE, "ingress_channels")), #{default => []})}
+    , {egress_channels, hoconsc:mk(hoconsc:map(id, hoconsc:ref(?MODULE, "egress_channels")), #{default => []})}
     ] ++ emqx_connector_schema_lib:ssl_fields();
 
 fields("ingress_channels") ->
@@ -61,9 +61,6 @@ fields("replayq") ->
     ].
 
 common_inout_confs() ->
-    [{id, #{type => binary(), nullable => false}}] ++ publish_confs().
-
-publish_confs() ->
     [ {qos, hoconsc:mk(qos(), #{default => <<"${qos}">>})}
     , {retain, hoconsc:mk(hoconsc:union([boolean(), binary()]), #{default => <<"${retain}">>})}
     , {payload, hoconsc:mk(binary(), #{default => <<"${payload}">>})}