logger

type Level uint8

type Logger interface {
	WithFields(fields map[string]interface{}) Logger
	Output() io.Writer
	SetOutput(w io.Writer)
	Level() Level
	SetLevel(level Level)
	InfoWriter() io.Writer
	ErrorWriter() io.Writer
	FatalWriter() io.Writer
	Debug(args ...interface{})
	Info(args ...interface{})
	Warn(args ...interface{})
	Error(args ...interface{})
	Fatal(args ...interface{})
	Panic(args ...interface{})
	Debugf(format string, args ...interface{})
	Infof(format string, args ...interface{})
	Warnf(format string, args ...interface{})
	Errorf(format string, args ...interface{})
	Fatalf(format string, args ...interface{})
	Panicf(format string, args ...interface{})
	Debugln(args ...interface{})
	Infoln(args ...interface{})
	Warnln(args ...interface{})
	Errorln(args ...interface{})
	Fatalln(args ...interface{})
	Panicln(args ...interface{})
}