packagelogrus// A hook to be fired when logging on the logging levels returned from// `Levels()` on your implementation of the interface. Note that this is not// fired in a goroutine or a channel with workers, you should handle such// functionality yourself if your call is non-blocking and you don't wish for// the logging calls for levels returned from `Levels()` to block.typeHookinterface{Levels()[]LevelFire(*Entry)error}// Internal type for storing the hooks on a logger instance.typeLevelHooksmap[Level][]Hook// Add a hook to an instance of logger. This is called with// `log.Hooks.Add(new(MyHook))` where `MyHook` implements the `Hook` interface.func(hooksLevelHooks)Add(hookHook){for_,level:=rangehook.Levels(){hooks[level]=append(hooks[level],hook)}}// Fire all the hooks for the passed level. Used by `entry.log` to fire// appropriate hooks for a log entry.func(hooksLevelHooks)Fire(levelLevel,entry*Entry)error{for_,hook:=rangehooks[level]{iferr:=hook.Fire(entry);err!=nil{returnerr}}returnnil}