GO ZK WATCH監聽

package main
 
import (
    "fmt"
    "github.com/samuel/go-zookeeper/zk"
    "strings"
    "time"
)
 
func must(err error) {
    if err != nil {
        panic(err)
    }
}
 
func connect() *zk.Conn {
    servers := strings.Split("127.0.0.1:2181", ",")
    conn, _, err := zk.Connect(servers, time.Second)
    must(err)
    return conn
}
 
func mirror(conn *zk.Conn, path string) (chan []string, chan error) {
    snapshots := make(chan []string)
    errors := make(chan error)
 
    go func() {
        for {
            snapshot, _, events, err := conn.ChildrenW(path)
            if err != nil {
                errors <- err
                return
            }
            snapshots <- snapshot
            evt := <-events
            if evt.Err != nil {
                errors <- evt.Err
                return
            }
        }
    }()
 
    return snapshots, errors
}
 
func main() {
    conn1 := connect()
    defer conn1.Close()
 
    flags := int32(zk.FlagEphemeral)
    acl := zk.WorldACL(zk.PermAll)
 
    _, err := conn1.Create("/mirror", nil, int32(0), acl)
    if err != nil {
        fmt.Printf("create: %+v\n", err)
    }
 
    snapshots, errors := mirror(conn1, "/mirror")
    go func() {
        for {
            select {
            case snapshot := <-snapshots:
                fmt.Printf("%+v\n", snapshot)
            case err := <-errors:
                fmt.Printf("%+v\n", err)
            }
        }
    }()
 
    conn2 := connect()
    time.Sleep(time.Second)
 
    _, err = conn2.Create("/mirror/one", []byte("one"), flags, acl)
    must(err)
    time.Sleep(time.Second)
 
    _, err = conn2.Create("/mirror/two", []byte("two"), flags, acl)
    must(err)
    time.Sleep(time.Second)
 
    err = conn1.Delete("/mirror/two", 0)
    must(err)
    time.Sleep(time.Second)
 
    _, err = conn2.Create("/mirror/three", []byte("three"), flags, acl)
    must(err)
    time.Sleep(time.Second)
 
    conn2.Close()
    time.Sleep(time.Second)
}