Using watch with new etcd 2.2 golang library

etcd22_watcher.go

package main

import (
        "github.com/coreos/etcd/client"
         "github.com/coreos/etcd/Godeps/_workspace/src/golang.org/x/net/context"
        "log"
        "time"
)

func main() {
        cfg := client.Config{
                Endpoints: []string{"http://127.0.0.1:4001"},
                Transport: client.DefaultTransport,
                // set timeout per request to fail fast when the target endpoint is unavailable
                HeaderTimeoutPerRequest: time.Second,
        }
        c, err := client.New(cfg)
        if err != nil {
                log.Fatal(err)
        }
        kapi := client.NewKeysAPI(c)
        watcherOpts := client.WatcherOptions{AfterIndex: 0, Recursive: true}
        w := kapi.Watcher("/base", &watcherOpts)
        for {
          r,err := w.Next(context.Background())
          if err != nil {
            log.Fatal("Error occurred", err)
          }
          action := r.Action
          // do something with Response r here
          log.Printf("action %s", action)
        }
}