eLog/include/rum.hrl

-define(RumDefTruncation, 4096).
-define(RumDefTracer, lager_default_tracer).
-define(RumDefSink, lager_event).
-define(RumErrLogSink, error_logger_lager_event).

-define(RumMetadata(Extras), [
   {severity, info},
   {pid, self()},
   {node, node()},
   {module, ?MODULE},
   {function, ?FUNCTION_NAME},
   {function_arity, ?FUNCTION_ARITY},
   {file, ?FILE},
   {line, ?LINE} | Extras
]).


-define(RumLevels, [debug, info, notice, warning, error, critical, alert, emergency, none]).

%% 使用这些“功能”意味着，出于安全考虑，参数列表不会被截断
-define(RumLevelsUnsafe, [{debug_unsafe, debug}, {info_unsafe, info}, {notice_unsafe, notice}, {warning_unsafe, warning}, {error_unsafe, error}, {critical_unsafe, critical}, {alert_unsafe, alert}, {emergency_unsafe, emergency}]).

-define(DEBUG, 128).
-define(INFO, 64).
-define(NOTICE, 32).
-define(WARNING, 16).
-define(ERROR, 8).
-define(CRITICAL, 4).
-define(ALERT, 2).
-define(EMERGENCY, 1).
-define(LOG_NONE, 0).

-define(RumLevelToNum(Level),
   case Level of
      debug -> ?DEBUG;
      info -> ?INFO;
      notice -> ?NOTICE;
      warning -> ?WARNING;
      error -> ?ERROR;
      critical -> ?CRITICAL;
      alert -> ?ALERT;
      emergency -> ?EMERGENCY
   end).

-define(RumNumToLevel(Num),
   case Num of
      ?DEBUG -> debug;
      ?INFO -> info;
      ?NOTICE -> notice;
      ?WARNING -> warning;
      ?ERROR -> error;
      ?CRITICAL -> critical;
      ?ALERT -> alert;
      ?EMERGENCY -> emergency
   end).

-define(RunShouldLog(Sink, Level), (rumUtil:level_to_num(Level) band element(1, rumConfig:get({Sink, loglevel}, {?LOG_NONE, []}))) /= 0).

-define(RunShouldLog(Level), (rumUtil:level_to_num(Level) band element(1, rumConfig:get(loglevel, {?LOG_NONE, []}))) /= 0).

-define(RunNotify(Level, Pid, Format, Args),
   gen_event:notify(lager_event, {log, rumMsg:new(io_lib:format(Format, Args), Level, [{pid, Pid}, {line, ?LINE}, {file, ?FILE}, {module, ?MODULE}], [])})).

%%仅供内部使用仅内部非阻塞日志记录调用，当我们仍在启动大型啤酒时尝试进行日志记录（通常为错误）时，会有一些特殊处理。
-ifdef(TEST).
-define(INT_LOG(Level, Format, Args),
   case ?RunShouldLog(Level) of
      true ->
         ?RunNotify(Level, self(), Format, Args);
      _ ->
         ok
   end).
-else.
-define(INT_LOG(Level, Format, Args),
   Self = self(),
   %% do this in a spawn so we don't cause a deadlock calling gen_event:which_handlers
   %% from a gen_event handler
   spawn(fun() ->
      case catch (gen_event:which_handlers(lager_event)) of
         X when X == []; X == {'EXIT', noproc}; X == [lager_backend_throttle] ->
            %% there's no handlers yet or lager isn't running, try again
            %% in half a second.
            timer:sleep(500),
            ?RunNotify(Level, Self, Format, Args);
         _ ->
            case ?RunShouldLog(Level) of
               true ->
                  ?RunNotify(Level, Self, Format, Args);
               _ ->
                  ok
            end
      end
         end)).
-endif.

-define(rumLog(Severity, Format, Args, Safety),
   ?rumLog(?RumDefSink, Severity, ?RumMetadata(eRum:md()), Format, Args, ?RumDefTruncation, Safety)).

-define(rumLog(Severity, Metadata, Format, Args, Safety),
   ?rumLog(?RumDefSink, Severity, ?RumMetadata(Metadata ++ eRum:md()), Format, Args, ?RumDefTruncation, Safety)).

-define(rumLog(Sink, Severity, Metadata, Format, Args, Size, Safety),
   _ = eRum:dispatch_log(Sink, Severity, Metadata, Format, Args, Size, Safety)).

-define(rumDebug(Format, Args), ?rumLog(debug, Format, Args, safe)).
-define(rumDebug(Metadata, Format, Args), ?rumLog(debug, Metadata, Format, Args, safe)).

-define(rumInfo(Format, Args), ?rumLog(info, Format, Args, safe)).
-define(rumInfo(Metadata, Format, Args), ?rumLog(info, Metadata, Format, Args, safe)).

-define(rumNotice(Format, Args), ?rumLog(notice, Format, Args, safe)).
-define(rumNotice(Metadata, Format, Args), ?rumLog(notice, Metadata, Format, Args, safe)).

-define(rumWarning(Format, Args), ?rumLog(warning, Format, Args, safe)).
-define(rumWarning(Metadata, Format, Args), ?rumLog(warning, Metadata, Format, Args, safe)).

-define(rumError(Format, Args), ?rumLog(error, Format, Args, safe)).
-define(rumError(Metadata, Format, Args), ?rumLog(error, Metadata, Format, Args, safe)).

-define(rumCritical(Format, Args), ?rumLog(critical, Format, Args, safe)).
-define(rumCritical(Metadata, Format, Args), ?rumLog(critical, Metadata, Format, Args, safe)).

-define(rumAlert(Format, Args), ?rumLog(alert, Format, Args, safe)).
-define(rumAlert(Metadata, Format, Args), ?rumLog(alert, Metadata, Format, Args, safe)).

-define(rumEmergency(Format, Args), ?rumLog(emergency, Format, Args, safe)).
-define(rumEmergency(Metadata, Format, Args), ?rumLog(emergency, Metadata, Format, Args, safe)).

-define(rumNone(Format, Args), ?rumLog(none, Format, Args, safe)).
-define(rumNone(Metadata, Format, Args), ?rumLog(none, Metadata, Format, Args, safe)).

-record(rumShaper, {
   id :: any()
   %% 每秒我们尝试传递多少消息
   , hwm = undefined :: 'undefined' | pos_integer()
   %% 这秒内我们收到了多少条消息
   , mps = 0 :: non_neg_integer()
   %% 当前秒
   , lastTime = os:timestamp() :: erlang:timestamp()
   %% 此秒内丢弃的消息数
   , dropped = 0 :: non_neg_integer()
   %% If true, flush notify messages from msg queue at overload
   %% 如果为true，则在过载时刷新来自消息队列的通知消息
   , flushQueue = true :: boolean()
   , flushThreshold = 0 :: integer()
   %% timer
   , timer = make_ref() :: reference()
   %% optional filter fun to avoid counting suppressed messages against HWM totals
   %% 可选的过滤器函数，以避免对HWM总数计算抑制消息
   , filter = fun(_) -> false end :: fun()
}).

-record(rumMsg, {
   destinations :: list(),
   metadata :: [tuple()],
   severity :: eRum:log_level(),
   datetime :: {string(), string()},
   timestamp :: erlang:timestamp(),
   message :: list()
}).

-type rumShaper() :: #rumShaper{}.