golang 中 etcd 基本用法

介绍

ETCD ： 高可用的分布式key-value存储，可以用于配置共享和服务发现。
类似项目：zookeeper和consul

import (
    "github.com/coreos/go-etcd/etcd"
    "log"
)

var (
    client *etcd.Client
    machines = []string{"http://127.0.0.1:2379"}
)

// 在初始化方法中创建 etcd 客户端
func init()  {
    client = etcd.NewClient(machines)
    log.Print("etcd client create success")
}

// 设置key值
func SetKey(key,value string,ttl uint64) {
    if nil == client {
        log.Fatal("etcd client is nil")
        return
    }
    if _, err := client.Set(key, value, ttl); err != nil {
        log.Fatal(err)
    }
}

// 获取key值
func GetKey(key string)  {
    if nil == client {
        log.Fatal("etcd client is nil")
        return
    }
    resp, err := client.Get(key, false, false)
    if err != nil {
        log.Fatal(err)
    }
    log.Printf("Current creds: %s: %s\n", resp.Node.Key, resp.Node.Value)
}

// 监听key值的滨化
func WatchKey(key string)  {
    if nil == client {
        log.Fatal("etcd client is nil")
        return
    }
    receiver := make(chan *etcd.Response)
    stopChan := make(chan bool)
    go client.Watch(key,0,false,receiver,stopChan)
    for  {
        select {
        case r := <-receiver:
            if r.Node.Value == "stop"{
                stopChan<- true
                log.Println("get stop")
                return
            }
            log.Printf("Got updated creds: %s: %s\n", r.Node.Key, r.Node.Value)

        }
    }
}

func Close()  {
    if nil != client {
        client.Close()
    }
    log.Println("Stop")
}