func Warn(a ...interface{}) (n int, err error) {
	if logLevel > util.LOG_WARN {
		return 0, nil
	}
	str := []interface{}{"[WARN]"}
	return fmt.Println(append(str, a)...)
}
Warn Warn level log
package logger
import (
	"fmt"
	"github.com/moxiaomomo/goRaft/util"
)
var logLevel util.LogLevelEnum = util.LOG_INFO
func SetLogLevel(level util.LogLevelEnum) {
	logLevel = level
}
func Debug(a ...interface{}) (n int, err error) {
	if logLevel > util.LOG_DEBUG {
		return 0, nil
	}
	str := []interface{}{"[DEBUG]"}
	return fmt.Println(append(str, a)...)
}
func Info(a ...interface{}) (n int, err error) {
	if logLevel > util.LOG_INFO {
		return 0, nil
	}
	str := []interface{}{"[INFO]"}
	return fmt.Println(append(str, a)...)
}