fix(log): client id as string for log metadata

so it does not print <<"...">> to the logs

src/emqx_logger.erl

@@ -138,7 +138,15 @@ critical(Metadata, Format, Args) when is_map(Metadata) ->
 set_metadata_clientid(<<>>) ->
     ok;
 set_metadata_clientid(ClientId) ->
-    set_proc_metadata(#{clientid => ClientId}).
+    try
+        %% try put string format client-id metadata so
+        %% so the log is not like <<"...">>
+        Id = unicode:characters_to_list(ClientId, utf8),
+        set_proc_metadata(#{clientid => Id})
+    catch
+        _: _->
+            ok
+    end.
 
 -spec(set_metadata_peername(peername_str()) -> ok).
 set_metadata_peername(Peername) ->

src/emqx_tracer.erl

@@ -145,17 +145,19 @@ handler_id(?TOPIC_TRACE(Topic)) ->
 handler_id(?CLIENT_TRACE(ClientId)) ->
     list_to_atom(?CLIENT_TRACE_ID(handler_name(ClientId))).
 
-filter_by_meta_key(#{meta:=Meta}=LogEvent, {MetaKey, MetaValue}) ->
-    case maps:find(MetaKey, Meta) of
-        {ok, MetaValue} -> LogEvent;
-        {ok, Topic} when MetaKey =:= topic ->
-            case emqx_topic:match(Topic, MetaValue) of
-                true -> LogEvent;
-                false -> ignore
-            end;
-        _ -> ignore
+filter_by_meta_key(#{meta := Meta} = Log, {Key, Value}) ->
+    case is_meta_match(Key, Value, Meta) of
+        true -> Log;
+        false -> ignore
     end.
 
+is_meta_match(clientid, ClientId, #{clientid := ClientIdStr}) ->
+    ClientId =:= iolist_to_binary(ClientIdStr);
+is_meta_match(topic, TopicFilter, #{topic := TopicMeta}) ->
+    emqx_topic:match(TopicMeta, TopicFilter);
+is_meta_match(_, _, _) ->
+    false.
+
 handler_name(Bin) ->
     case byte_size(Bin) of
         Size when Size =< 200 -> binary_to_list(Bin);

test/emqx_tracer_SUITE.erl

@@ -33,7 +33,6 @@ init_per_suite(Config) ->
 end_per_suite(_Config) ->
     emqx_ct_helpers:stop_apps([]).
 
-
 t_start_traces(_Config) ->
     {ok, T} = emqtt:start_link([{host, "localhost"},
                                 {clientid, <<"client">>},