Exemple #1
0
// Find possible addresses for cluster named name.
func lookup(b *doozer.Conn, name string) (as []string) {
	rev, err := b.Rev()
	if err != nil {
		panic(err)
	}

	info, err := b.Walk("/ctl/ns/"+name+"/*", rev, 0, -1)
	if err != nil {
		panic(err)
	}
	for _, e := range info {
		as = append(as, string(e.Body))
	}
	return as
}
Exemple #2
0
func Main(clusterName, self, buri, secret string, cl *doozer.Conn, udpConn net.PacketConn, listener, webListener net.Listener, pulseInterval, fillDelay, kickTimeout int64) {
	listenAddr := listener.Addr().String()

	canWrite := make(chan bool, 1)
	in := make(chan consensus.Packet, 50)
	out := make(chan consensus.Packet, 50)

	st := store.New()
	pr := &proposer{
		seqns: make(chan int64, alpha),
		props: make(chan *consensus.Prop),
		st:    st,
	}

	calSrv := func(start int64) {
		go gc.Pulse(self, st.Seqns, pr, pulseInterval)
		go gc.Clean(st, 360000, time.Tick(1e9))
		consensus.NewManager(self, start, alpha, in, out, st.Ops, pr.seqns, pr.props, fillDelay, st)
	}

	if cl == nil { // we are the only node in a new cluster
		set(st, "/ctl/name", clusterName, store.Missing)
		set(st, "/ctl/node/"+self+"/addr", listenAddr, store.Missing)
		set(st, "/ctl/node/"+self+"/hostname", os.Getenv("HOSTNAME"), store.Missing)
		set(st, "/ctl/node/"+self+"/version", Version, store.Missing)
		set(st, "/ctl/cal/0", self, store.Missing)
		calSrv(<-st.Seqns)
		// Skip ahead alpha steps so that the registrar can provide a
		// meaningful cluster.
		for i := 0; i < alpha; i++ {
			st.Ops <- store.Op{1 + <-st.Seqns, store.Nop}
		}
		canWrite <- true
	} else {
		setC(cl, "/ctl/node/"+self+"/addr", listenAddr, store.Clobber)
		setC(cl, "/ctl/node/"+self+"/hostname", os.Getenv("HOSTNAME"), store.Clobber)
		setC(cl, "/ctl/node/"+self+"/version", Version, store.Clobber)

		rev, err := cl.Rev()
		if err != nil {
			panic(err)
		}

		stop := make(chan bool, 1)
		go follow(st, cl, rev+1, stop)

		info, err := cl.Walk("/**", rev, 0, -1)
		if err != nil {
			panic(err)
		}
		for _, ev := range info {
			// store.Clobber is okay here because the event
			// has already passed through another store
			mut := store.MustEncodeSet(ev.Path, string(ev.Body), store.Clobber)
			st.Ops <- store.Op{ev.Rev, mut}
		}
		st.Flush()

		ch, err := st.Wait(store.Any, rev+1)
		if err == nil {
			<-ch
		}

		go func() {
			n := activate(st, self, cl)
			calSrv(n)
			advanceUntil(cl, st.Seqns, n+alpha)
			stop <- true
			canWrite <- true
			if buri != "" {
				b, err := doozer.DialUri(buri)
				if err != nil {
					panic(err)
				}
				setC(
					b,
					"/ctl/ns/"+clusterName+"/"+self,
					listenAddr,
					store.Missing,
				)
			}
		}()
	}

	shun := make(chan string, 3) // sufficient for a cluster of 7
	go member.Clean(shun, st, pr)
	go server.ListenAndServe(listener, canWrite, st, pr, secret)

	if secret == "" && webListener != nil {
		web.Store = st
		web.ClusterName = clusterName
		go web.Serve(webListener)
	}

	go func() {
		for p := range out {
			addr, err := net.ResolveUDPAddr(p.Addr)
			if err != nil {
				log.Println(err)
				continue
			}
			n, err := udpConn.WriteTo(p.Data, addr)
			if err != nil {
				log.Println(err)
				continue
			}
			if n != len(p.Data) {
				log.Println("packet len too long:", len(p.Data))
				continue
			}
		}
	}()

	lv := liveness{
		timeout: kickTimeout,
		ival:    kickTimeout / 2,
		times:   make(map[string]int64),
		self:    self,
		shun:    shun,
	}
	for {
		t := time.Nanoseconds()

		buf := make([]byte, maxUDPLen)
		n, addr, err := udpConn.ReadFrom(buf)
		if err == os.EINVAL {
			return
		}
		if err != nil {
			log.Println(err)
			continue
		}

		buf = buf[:n]

		// Update liveness time stamp for this addr
		lv.times[addr.String()] = t
		lv.check(t)

		in <- consensus.Packet{addr.String(), buf}
	}
}