golang基于etcd做分布式任务锁

博客参考相关链接,提到etcd服务搭建看上一篇,直接给出Go语言获取etcd包的代码,还展示了main.go内容及程序输出,转载自另一链接。

摘要生成于 C知道 ,由 DeepSeek-R1 满血版支持, 前往体验 >

参考:https://www.jianshu.com/p/d7434d916856

etcd服务搭建请看上一篇,下面直接上代码:

# go get github.com/etcd-io/etcd

main.go 内容如下:

package main

import (
"context"
"fmt"
"time"
//"github.com/etcd-io/etcd/clientv3" 这个引用会导致启动失败
"go.etcd.io/etcd/clientv3"
)

//锁结构体
type EtcdMutex struct {
Ttl int64 //租约时间
Conf clientv3.Config //etcd集群配置
Key string //etcd的key
cancel context.CancelFunc //关闭续租的func
lease clientv3.Lease
leaseID clientv3.LeaseID
txn clientv3.Txn
}

//初始化锁
func (em *EtcdMutex) init() error {
var err error
var ctx context.Context
client,err := clientv3.New(em.Conf)
if err != nil{
return err
}
em.txn = clientv3.NewKV(client).Txn(context.TODO())
em.lease = clientv3.NewLease(client)
leaseResp,err := em.lease.Grant(context.TODO(),em.Ttl)
if err != nil{
return err
}
ctx,em.cancel = context.WithCancel(context.TODO())
em.leaseID = leaseResp.ID
leaseRespChan,err := em.lease.KeepAlive(ctx,em.leaseID)
  //启动一个协程去监听续租情况 (不然一会儿就会写满keepalive的队列,导致大量异常日是志)
  go listenLeaseChan(leaseRespChan)
  return err
}
func listenLeaseChan(leaseRespChan <-chan *clientv3.LeaseKeepAliveResponse) {
var (
leaseKeepResp *clientv3.LeaseKeepAliveResponse
)
for {
select {
case leaseKeepResp = <-leaseRespChan:
if leaseKeepResp == nil {
fmt.Println("租约失效了")
goto END
}
}
}
END:
}

//获取锁
func (em *EtcdMutex) Lock() error {
err := em.init()
if err != nil{
return err
}
//LOCK:
em.txn.If(clientv3.Compare(clientv3.CreateRevision(em.Key),"=",0)).
Then(clientv3.OpPut(em.Key,"",clientv3.WithLease(em.leaseID))).
Else()
txnResp,err := em.txn.Commit()
if err != nil{
return err
}
if !txnResp.Succeeded{ //判断txn.if条件是否成立
return fmt.Errorf("抢锁失败")
}
return nil
}

//释放锁
func(em *EtcdMutex) UnLock() {
em.cancel()
em.lease.Revoke(context.TODO(),em.leaseID)
fmt.Println("释放了锁")
}

func EtcdTest() {
fmt.Println("start etcd connect ...")
var conf = clientv3.Config{
Endpoints: []string{"172.16.4.67:2379"},
DialTimeout: 5 * time.Second,
}
eMutex1 := &EtcdMutex{
Conf:conf,
Ttl:10,
Key:"lock",
}
eMutex2 := &EtcdMutex{
Conf:conf,
Ttl:10,
Key:"lock",
}
//groutine1
go func() {
fmt.Println("groutine1")
err := eMutex1.Lock()
fmt.Println(err)
if err != nil {
fmt.Println("groutine1抢锁失败")
fmt.Println(err)
return
}
fmt.Println("groutine1抢锁成功")
time.Sleep(10*time.Second)
defer eMutex1.UnLock()
}()

//groutine2
go func() {
fmt.Println("groutine2")
err := eMutex2.Lock()
fmt.Println(err)
if err != nil {
fmt.Println("groutine2抢锁失败")
fmt.Println(err)
return
}
fmt.Println("groutine2抢锁成功")
defer eMutex2.UnLock()
}()
time.Sleep(300*time.Second)
}

程序输出如下:

 

转载于:https://www.cnblogs.com/chmyee/p/10949933.html

评论
添加红包

请填写红包祝福语或标题

红包个数最小为10个

红包金额最低5元

当前余额3.43前往充值 >
需支付:10.00
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值