golang]使用redis实现简单的分布式锁

https://github.com/study-only/go-locks

Redis分布式锁

SET

Redis 2.6.12SET

SET key value [EX seconds] [PX milliseconds] [NX|XX]

可选参数

EX secondssecondsSET key value EX secondsSETEX key seconds valuePX millisecondsmillisecondsSET key value PX millisecondsPSETEX key milliseconds valueNXSET key value NXSETNX key valueXX

返回值

Redis 2.6.12SETRedis 2.6.12SETOKNXXX

Redis分布式锁实现原理

SETSET key value EX seconds NX

import (
    "errors"
    "time"
    "github.com/go-redis/redis"
)

var redisClient *redis.Client

type redisLock struct {
    name    string
    expiry  time.Duration
}

func (l *redisLock) TryLock() error {
    if ok, _ := redisClient.SetNX(l.name, 1, l.expiry).Result(); !ok {
        return errors.New("redis lock: already locked")
    }

    return nil
}

func (l *redisLock) Unlock() error {
    return redisClient.Del(l.name).Err()
}