log

type Level int32

type Options struct {
	// OutputPath is a file system path to write the log data to.
	// The special values stdout and stderr can be used to output to the
	// standard I/O streams. This defaults to stdout.
	OutputPath string

	// ErrorOutputPath is a file system path to write logger errors to.
	// The special values stdout and stderr can be used to output to the
	// standard I/O streams. This defaults to stderr.
	ErrorOutputPath string

	// RotateOutputPath is the path to a rotating log file. This file should
	// be automatically rotated over time, based on the rotation parameters such
	// as RotationMaxSize and RotationMaxAge. The default is to not rotate.
	//
	// This path is used as a foundational path. This is where log output is normally
	// saved. When a rotation needs to take place because the file got too big or too
	// old, then the file is renamed by appending a timestamp to the name. Such renamed
	// files are called backups. Once a backup has been created,
	// output resumes to this path.
	RotateOutputPath string

	// RotationMaxSize is the maximum size in megabytes of a log file before it gets
	// rotated. It defaults to 100 megabytes.
	RotationMaxSize int

	// RotationMaxAge is the maximum number of days to retain old log files based on the
	// timestamp encoded in their filename. Note that a day is defined as 24
	// hours and may not exactly correspond to calendar days due to daylight
	// savings, leap seconds, etc. The default is to remove log files
	// older than 30 days.
	RotationMaxAge int

	// RotationMaxBackups is the maximum number of old log files to retain.  The default
	// is to retain at most 1000 logs.
	RotationMaxBackups int

	// JSONEncoding controls whether the log is formatted as JSON.
	JSONEncoding bool

	// OutputLevel controls the log level.
	OutputLevel string

	// StackTraceLevel controls the log level for stack trace.
	StackTraceLevel string

	// LogCaller controls whether to log the caller of a logging function
	LogCaller bool
}