refactor(logger): stop using anonymous fun for logging

apps/emqx/include/logger.hrl

@@ -14,10 +14,12 @@
 %% limitations under the License.
 %%--------------------------------------------------------------------
 
-%% debug | info | notice | warning | error | critical | alert | emergency
+-ifndef(EMQX_LOGGER_HRL).
+-define(EMQX_LOGGER_HRL, true).
 
 -compile({parse_transform, emqx_logger}).
 
+%% debug | info | notice | warning | error | critical | alert | emergency
 -define(DEBUG(Format), ?LOG(debug, Format, [])).
 -define(DEBUG(Format, Args), ?LOG(debug, Format, Args)).
 
@@ -41,10 +43,21 @@
 
 -define(LOG(Level, Format), ?LOG(Level, Format, [])).
 
--define(LOG(Level, Format, Args),
-        begin
-          (logger:log(Level,#{},#{report_cb => fun(_) -> {'$logger_header'()++(Format), (Args)} end,
-                                  mfa => {?MODULE, ?FUNCTION_NAME, ?FUNCTION_ARITY},
-                                  line => ?LINE}))
+-define(LOG(Level, Format, Args, Meta),
+        %% check 'allow' here so we do not have to pass an anonymous function
+        %% down to logger which may cause `badfun` exception during upgrade
+        case logger:allow(Level, ?MODULE) of
+            true ->
+                logger:log(Level, (Format), (Args),
+                           (Meta)#{ mfa => <<(atom_to_binary(?MODULE, utf8))/binary, $:,
+                                             (atom_to_binary(?FUNCTION_NAME, utf8))/binary, $/,
+                                             (integer_to_binary(?FUNCTION_ARITY))/binary>>
+                                  , line => ?LINE
+                                  });
+            false ->
+                ok
         end).
 
+-define(LOG(Level, Format, Args), ?LOG(Level, Format, Args, #{})).
+
+-endif.

apps/emqx/src/emqx_logger_jsonfmt.erl

@@ -197,12 +197,18 @@ json_obj(Data, Config) ->
                       json_kv(K, V, D, Config)
               end, maps:new(), Data).
 
-json_kv(mfa, {M, F, A}, Data, _Config) -> %% emqx/snabbkaffe
+json_kv(mfa, {M, F, A}, Data, _Config) -> %% snabbkaffe
     maps:put(mfa, <<(atom_to_binary(M, utf8))/binary, $:,
                     (atom_to_binary(F, utf8))/binary, $/,
                     (integer_to_binary(A))/binary>>, Data);
 json_kv('$kind', Kind, Data, Config) -> %% snabbkaffe
     maps:put(msg, json(Kind, Config), Data);
+json_kv(gl, _, Data, _Config) ->
+    %% drop gl because it's not interesting
+    Data;
+json_kv(file, _, Data, _Config) ->
+    %% drop 'file' because we have mfa
+    Data;
 json_kv(K0, V, Data, Config) ->
     K = json_key(K0),
     case is_map(V) of

apps/emqx/src/emqx_logger_textfmt.erl

@@ -26,6 +26,7 @@
         , peername  % formatted as a part of templated message
         , clientid  % formatted as a part of templated message
         , gl        % not interesting
+        , file
         ]).
 
 check_config(X) -> logger_formatter:check_config(X).