log

type Fields map[string]interface{}

type Logger interface {
	SetOutput(out io.Writer)
	SetLevel(v uint32)
	GetLevel() uint32
	Close()

	WriterContext
}

type Sender interface {
	PutEntity(v *entity)
	SendMessage(level uint32, call func(v *message))
	Close()
}

type Writer interface {
	Fatalf(format string, args ...interface{})
	Errorf(format string, args ...interface{})
	Warnf(format string, args ...interface{})
	Infof(format string, args ...interface{})
	Debugf(format string, args ...interface{})
}

type WriterContext interface {
	WithError(key string, err error) Writer
	WithField(key string, value interface{}) Writer
	WithFields(Fields) Writer
	Writer
}