示例#1
0
文件: cell.go 项目: henryanand/vitess
// background routine to initiate a connection sequence
// only connect if state == CELL_DISCONNECTED
// will change state to CELL_CONNECTING during the connection process
// will then change to CELL_CONNECTED (and braodcast the cond)
// or to CELL_BACKOFF (and schedule a new reconnection soon)
func (zcell *zkCell) connect() {
	// change our state, we're working on connecting
	zcell.mutex.Lock()
	if zcell.state != CELL_DISCONNECTED {
		// someone else is already connecting
		zcell.mutex.Unlock()
		return
	}
	zcell.state = CELL_CONNECTING
	zcell.mutex.Unlock()

	// now connect
	zconn, session, err := zk.DialZkTimeout(zcell.zkAddr, *baseTimeout, *connectTimeout)
	if err == nil {
		zcell.zconn = zconn
		go zcell.handleSessionEvents(session)
	}

	// and change our state
	zcell.mutex.Lock()
	if zcell.state != CELL_CONNECTING {
		panic(fmt.Errorf("Unexpected state: %v", zcell.state))
	}
	if err == nil {
		log.Infof("zk cell conn: cell %v connected", zcell.cellName)
		zcell.state = CELL_CONNECTED
		zcell.lastErr = nil

	} else {
		log.Infof("zk cell conn: cell %v connection failed: %v", zcell.cellName, err)
		zcell.state = CELL_BACKOFF
		zcell.lastErr = err

		go func() {
			// we're going to try to reconnect at some point
			// FIXME(alainjobart) backoff algorithm?
			<-time.NewTimer(time.Duration(*reconnectInterval) * time.Second).C

			// switch back to DISCONNECTED, and trigger a connect
			zcell.mutex.Lock()
			zcell.state = CELL_DISCONNECTED
			zcell.mutex.Unlock()
			zcell.connect()
		}()
	}

	// we broadcast on the condition to get everybody unstuck,
	// whether we succeeded to connect or not
	zcell.ready.Broadcast()
	zcell.mutex.Unlock()
}
示例#2
0
func main() {
	defer logutil.Flush()
	flag.Usage = func() {
		fmt.Fprintf(os.Stderr, "Usage of %v:\n", os.Args[0])
		flag.PrintDefaults()
		fmt.Fprintf(os.Stderr, doc)
	}
	flag.Parse()
	args := flag.Args()
	if len(args) == 0 {
		flag.Usage()
		os.Exit(1)
	}

	if *zkAddrs != "" {
		if *zkoccAddr != "" {
			log.Fatalf("zk.addrs and zk.zkocc-addr are mutually exclusive")
		}
		var err error
		zconn, _, err = zk.DialZkTimeout(*zkAddrs, 5*time.Second, 10*time.Second)
		if err != nil {
			log.Fatalf("zk connect failed: %v", err.Error())
		}
	}

	if *zkoccAddr != "" {
		var err error
		zconn, err = zk.DialZkocc(*zkoccAddr, 5*time.Second)
		if err != nil {
			log.Fatalf("zkocc connect failed: %v", err.Error())
		}
	}

	cmdName := args[0]
	args = args[1:]
	if cmd, ok := cmdMap[cmdName]; ok {
		subFlags := flag.NewFlagSet(cmdName, flag.ExitOnError)
		cmd(subFlags, args)
	}
}