Add logger:update_formatter_config/2,3

5 files changed, 130 insertions, 6 deletions

diff --git a/lib/kernel/doc/src/logger.xml b/lib/kernel/doc/src/logger.xml
index f7e740e90d..be733685cc 100644
--- a/lib/kernel/doc/src/logger.xml
+++ b/lib/kernel/doc/src/logger.xml
@@ -774,6 +774,31 @@ logger:set_handler_config(HandlerId,maps:merge(Old,Config)).
     </func>
 
     <func>
+      <name name="update_formatter_config" arity="2"/>
+      <fsummary>Update the formatter configuration for the specified handler.</fsummary>
+      <desc>
+        <p>Update the formatter configuration for the specified handler.</p>
+	<p>The new configuration is merged with the existing formatter
+	  configuration.</p>
+	<p>To overwrite the existing configuration without any merge,
+	  use <seealso marker="#set_handler_config-3">
+	    <c>set_handler_config(HandlerId,formatter,
+	      {FormatterModule,FormatterConfig})</c></seealso>.</p>
+      </desc>
+    </func>
+
+    <func>
+      <name name="update_formatter_config" arity="3"/>
+      <fsummary>Update the formatter configuration for the specified handler.</fsummary>
+      <desc>
+        <p>Update the formatter configuration for the specified handler.</p>
+	<p>This is equivalent
+	  to <br/><seealso marker="#update_formatter_config-2">
+	    <c>update_formatter_config(<anno>HandlerId</anno>,#{<anno>Key</anno>=><anno>Value</anno>})</c></seealso></p>
+      </desc>
+    </func>
+
+    <func>
       <name name="compare_levels" arity="2"/>
       <fsummary>Compare the severity of two log levels.</fsummary>
       <desc>
diff --git a/lib/kernel/doc/src/logger_chapter.xml b/lib/kernel/doc/src/logger_chapter.xml
index 21b460e72a..522d0ce29d 100644
--- a/lib/kernel/doc/src/logger_chapter.xml
+++ b/lib/kernel/doc/src/logger_chapter.xml
@@ -157,7 +157,7 @@
 	  <p>A formatter is defined as a module exporting the following
 	    function:</p>
 
-	  <code>format(Log,Extra) -> unicode:chardata()</code>
+	  <code>format(Log,FConfig) -> unicode:chardata()</code>
 
 	  <p>The formatter callback is called by each handler, and the
 	    returned string can be printed to the handler's destination
@@ -413,12 +413,12 @@
 	    return <c>ignore</c>.</p>
 	  <p>Default is <c>log</c>.</p>
 	</item>
-	<tag><c>formatter = {Module::module(),Extra::term()}</c></tag>
+	<tag><c>formatter = {FModule::module(),FConfig::map()}</c></tag>
 	<item>
 	  <p>See <seealso marker="#Formatter">Formatter</seealso> for more
 	    information.</p>
 	  <p>The default module is <seealso marker="logger_formatter">
-	      <c>logger_formatter</c></seealso>, and <c>Extra</c> is
+	      <c>logger_formatter</c></seealso>, and <c>FConfig</c> is
 	      it's configuration map.</p>
 	</item>
         <tag>HandlerConfig, <c>term() = term()</c></tag>
diff --git a/lib/kernel/src/logger.erl b/lib/kernel/src/logger.erl
index 51743822af..d60be180bc 100644
--- a/lib/kernel/src/logger.erl
+++ b/lib/kernel/src/logger.erl
@@ -41,6 +41,7 @@
          set_logger_config/1, set_logger_config/2,
          set_handler_config/2, set_handler_config/3,
          update_logger_config/1, update_handler_config/2,
+         update_formatter_config/2, update_formatter_config/3,
          get_logger_config/0, get_handler_config/1,
          add_handlers/1]).
 
@@ -92,7 +93,7 @@
 -type config() :: #{level => level(),
                     filter_default => log | stop,
                     filters => [{filter_id(),filter()}],
-                    formatter => {module(),term()},
+                    formatter => {module(),map()},
                     term() => term()}.
 -type timestamp() :: integer().
 
@@ -386,6 +387,21 @@ get_logger_config() ->
 get_handler_config(HandlerId) ->
     logger_config:get(?LOGGER_TABLE,HandlerId).
 
+-spec update_formatter_config(HandlerId,FormatterConfig) ->
+                                     ok | {error,term()} when
+      HandlerId :: config(),
+      FormatterConfig :: map().
+update_formatter_config(HandlerId,FormatterConfig) ->
+    logger_server:update_formatter_config(HandlerId,FormatterConfig).
+
+-spec update_formatter_config(HandlerId,Key,Value) ->
+                                     ok | {error,term()} when
+      HandlerId :: config(),
+      Key :: atom(),
+      Value :: term().
+update_formatter_config(HandlerId,Key,Value) ->
+    logger_server:update_formatter_config(HandlerId,#{Key=>Value}).
+
 -spec set_module_level(Module,Level) -> ok | {error,term()} when
       Module :: module(),
       Level :: level().
diff --git a/lib/kernel/src/logger_server.erl b/lib/kernel/src/logger_server.erl
index 67befef156..18a784c8c2 100644
--- a/lib/kernel/src/logger_server.erl
+++ b/lib/kernel/src/logger_server.erl
@@ -27,7 +27,8 @@
          add_filter/2, remove_filter/2,
          set_module_level/2, reset_module_level/1,
          cache_module_level/1,
-         set_config/2, set_config/3, update_config/2]).
+         set_config/2, set_config/3, update_config/2,
+         update_formatter_config/2]).
 
 %% gen_server callbacks
 -export([init/1, handle_call/3, handle_cast/2, handle_info/2,
@@ -111,6 +112,13 @@ update_config(Owner, Config) ->
             Error
     end.
 
+update_formatter_config(HandlerId, FormatterConfig)
+  when is_map(FormatterConfig) ->
+    call({update_formatter_config,HandlerId,FormatterConfig});
+update_formatter_config(_HandlerId, FormatterConfig) ->
+    {error,{invalid_formatter_config,FormatterConfig}}.
+
+
 %%%===================================================================
 %%% gen_server callbacks
 %%%===================================================================
@@ -216,6 +224,22 @@ handle_call({set_config,HandlerId,Config}, From, #state{tid=Tid}=State) ->
         _ ->
             {reply,{error,{not_found,HandlerId}},State}
     end;
+handle_call({update_formatter_config,HandlerId,NewFConfig},_From,
+            #state{tid=Tid}=State) ->
+    Reply =
+        case logger_config:get(Tid,HandlerId) of
+            {ok,{_Mod,#{formatter:={FMod,OldFConfig}}=Config}} ->
+                try
+                    FConfig = maps:merge(OldFConfig,NewFConfig),
+                    check_formatter({FMod,FConfig}),
+                    do_set_config(Tid,HandlerId,
+                                  Config#{formatter=>{FMod,FConfig}})
+                catch throw:Reason -> {error,Reason}
+                end;
+            _ ->
+            {error,{not_found,HandlerId}}
+        end,
+    {reply,Reply,State};
 handle_call({set_module_level,Module,Level}, _From, #state{tid=Tid}=State) ->
     Reply = logger_config:set_module_level(Tid,Module,Level),
     {reply,Reply,State};
diff --git a/lib/kernel/test/logger_formatter_SUITE.erl b/lib/kernel/test/logger_formatter_SUITE.erl
index c171165944..934fe4deef 100644
--- a/lib/kernel/test/logger_formatter_SUITE.erl
+++ b/lib/kernel/test/logger_formatter_SUITE.erl
@@ -68,7 +68,8 @@ all() ->
      level_or_msg_in_meta,
      faulty_log,
      faulty_config,
-     faulty_msg].
+     faulty_msg,
+     update_config].
 
 default(_Config) ->
     String1 = format(info,{"~p",[term]},#{},#{}),
@@ -532,6 +533,54 @@ faulty_msg(_Config) ->
                                      #{})),
     ok.
 
+%% Test that formatter config can be changed, and that the default
+%% template is updated accordingly
+update_config(_Config) ->
+    logger:add_handler_filter(default,silence,{fun(_,_) -> stop end,ok}),
+    ok = logger:add_handler(?MODULE,?MODULE,#{}),
+    D = lists:seq(1,1000),
+    logger:info("~p~n",[D]),
+    {Lines1,C1} = check_log(),
+    [ct:log(L) || L <- Lines1],
+    ct:log("~p",[C1]),
+    [Line1] = Lines1,
+    [_Time,"info: "++D1] = string:split(Line1," "),
+    true = length(D1)>3000,
+    true = #{}==C1,
+
+    ok = logger:update_formatter_config(?MODULE,single_line,false),
+    logger:info("~p~n",[D]),
+    {Lines2,C2} = check_log(),
+    [ct:log(L) || L <- Lines2],
+    ct:log("~p",[C2]),
+    true = length(Lines2)>50,
+    true = #{single_line=>false}==C2,
+
+    ok = logger:update_formatter_config(?MODULE,#{legacy_header=>true}),
+    logger:info("~p~n",[D]),
+    {Lines3,C3} = check_log(),
+    [ct:log(L) || L <- Lines3],
+    ct:log("~p",[C3]),
+    ["=INFO REPORT==== "++_|D3] = Lines3,
+    true = length(D3)>50,
+    true = #{legacy_header=>true,single_line=>false}==C3,
+
+    ok = logger:update_formatter_config(?MODULE,single_line,true),
+    logger:info("~p~n",[D]),
+    {Lines4,C4} = check_log(),
+    [ct:log(L) || L <- Lines4],
+    ct:log("~p",[C4]),
+    ["=INFO REPORT==== "++_,D4] = Lines4,
+    true = length(D4)>3000,
+    true = #{legacy_header=>true,single_line=>true}==C4,
+
+    ok.
+
+update_config(cleanup,_Config) ->
+    _ = logger:remove_handler(?MODULE),
+    _ = logger:remove_handler_filter(default,silence),
+    ok.
+
 %%%-----------------------------------------------------------------
 %%% Internal
 format(Level,Msg,Meta,Config) ->
@@ -575,3 +624,13 @@ add_time(#{time:=_}=Meta) ->
     Meta;
 add_time(Meta) ->
     Meta#{time=>timestamp()}.
+
+%%%-----------------------------------------------------------------
+%%% handler callback
+log(Log,#{formatter:={M,C}}) ->
+    put(log,{M:format(Log,C),C}),
+    ok.
+
+check_log() ->
+    {S,C} = erase(log),
+    {string:lexemes(S,"\n"),C}.