这里使用官方的etcd/clientv3包来连接etcd并进行相关操作。

安装

  1. go get go.etcd.io/etcd/clientv3

put和get操作

put命令用来设置键值对数据，get命令用来根据key获取值。

  1. package main
  3. import (
  4.     "context"
  5.     "fmt"
  6.     "time"
  7.     "go.etcd.io/etcd/clientv3"
  8. )
  10. func main(){
  11.     cli, err := clientv3.New(clientv3.Config{
  12.         Endpoints:   []string{"122.51.79.172:2379"},
  13.         DialTimeout: 5 * time.Second,
  14.     })
  15.     if err != nil {
  16.         // handle error!
  17.         fmt.Printf("connect to etcd failed, err:%v\n", err)
  18.         return
  19.     }
  20.     fmt.Println("connect to etcd success")
  21.     defer cli.Close()
  22.     // put
  23.     ctx, cancel := context.WithTimeout(context.Background(), time.Second)
  24.     _, err = cli.Put(ctx, "coolops", "test")
  25.     cancel()
  26.     if err != nil {
  27.         fmt.Printf("put to etcd failed, err:%v\n", err)
  28.         return
  29.     }
  30.     // get
  31.     ctx, cancel = context.WithTimeout(context.Background(), time.Second)
  32.     resp, err := cli.Get(ctx, "coolops")
  33.     cancel()
  34.     if err != nil {
  35.         fmt.Printf("get from etcd failed, err:%v\n", err)
  36.         return
  37.     }
  38.     for _, ev := range resp.Kvs {
  39.         fmt.Printf("%s:%s\n", ev.Key, ev.Value)
  40.     }
  41. }

watch操作

watch用来获取未来更改的通知。

  1. package main
  3. import (
  4.     "context"
  5.     "fmt"
  6.     "time"
  7.     "go.etcd.io/etcd/clientv3"
  8. )
  10. func main(){
  11.     cli, err := clientv3.New(clientv3.Config{
  12.         Endpoints:   []string{"122.51.79.172:2379"},
  13.         DialTimeout: 5 * time.Second,
  14.     })
  15.     if err != nil {
  16.         // handle error!
  17.         fmt.Printf("connect to etcd failed, err:%v\n", err)
  18.         return
  19.     }
  20.     fmt.Println("connect to etcd success")
  21.     defer cli.Close()
  22.     // watch 操作，返回的是一个通道
  23.     rch := cli.Watch(context.Background(), "coolops") // <-chan WatchResponse
  24.     for wresp := range rch {
  25.         for _, ev := range wresp.Events {
  26.             fmt.Printf("Type: %s Key:%s Value:%s\n", ev.Type, ev.Kv.Key, ev.Kv.Value)
  27.         }
  28.     }
  29. }

安装报错：

  1. go: finding github.com/coreos/pkg latest
  2. # github.com/coreos/etcd/clientv3/balancer/resolver/endpoint
  3. E:\DEV\Go\pkg\mod\github.com\coreos\etcd@v3.3.19+incompatible\clientv3\balancer\resolver\endpoint\endpoint.go:114:78: undefined: resolver.BuildOption
  4. E:\DEV\Go\pkg\mod\github.com\coreos\etcd@v3.3.19+incompatible\clientv3\balancer\resolver\endpoint\endpoint.go:182:31: undefined: resolver.ResolveNowOption
  5. # github.com/coreos/etcd/clientv3/balancer/picker
  6. E:\DEV\Go\pkg\mod\github.com\coreos\etcd@v3.3.19+incompatible\clientv3\balancer\picker\err.go:37:44: undefined: balancer.PickOptions
  7. E:\DEV\Go\pkg\mod\github.com\coreos\etcd@v3.3.19+incompatible\clientv3\balancer\picker\roundrobin_balanced.go:55:54: undefined: balancer.PickOptions

解决：
将go.mod里的prpc改为1.26.0版本

  1. google.golang.org/grpc v1.26.0