func NewPrefixLogger(logger DepthLoggerV2, prefix string) *PrefixLogger {
	return &PrefixLogger{logger: logger, prefix: prefix}
}
NewPrefixLogger creates a prefix logger with the given prefix.
package grpclog
import (
	"fmt"
)
type PrefixLogger struct {
	logger DepthLoggerV2
	prefix string
}
func (pl *PrefixLogger) Infof(format string, args ...interface{}) {
	if pl != nil {
		format = pl.prefix + format
		pl.logger.InfoDepth(1, fmt.Sprintf(format, args...))
		return
	}
	InfoDepth(1, fmt.Sprintf(format, args...))
}
func (pl *PrefixLogger) Warningf(format string, args ...interface{}) {
	if pl != nil {
		format = pl.prefix + format
		pl.logger.WarningDepth(1, fmt.Sprintf(format, args...))
		return
	}
	WarningDepth(1, fmt.Sprintf(format, args...))
}
func (pl *PrefixLogger) Errorf(format string, args ...interface{}) {
	if pl != nil {
		format = pl.prefix + format
		pl.logger.ErrorDepth(1, fmt.Sprintf(format, args...))
		return
	}
	ErrorDepth(1, fmt.Sprintf(format, args...))
}
func (pl *PrefixLogger) Debugf(format string, args ...interface{}) {
	if !Logger.V(2) {
		return
	}
	if pl != nil {
		format = pl.prefix + format
		pl.logger.InfoDepth(1, fmt.Sprintf(format, args...))
		return
	}
	InfoDepth(1, fmt.Sprintf(format, args...))
}