report/log/logger.go
func (l *reportLogger) Printf(format string, v ...interface{}) {
	if l.logger != nil {
		l.logger.Debug(fmt.Sprintf(format, v...))
	}
}
func (l *reportLogger) Printf(format string, v ...interface{}) {
	if l.logger != nil {
		l.logger.Debug(fmt.Sprintf(format, v...))
	}
}
// Printf logs internal messages from a reporter.