Example #1
0
// Talk with local agent
func NewChannel(name string, port int, wg *sync.WaitGroup) (chan []byte, error) {
	ch := make(chan []byte)

	// connect to a TCP server
	network := "tcp"
	target := "localhost:" + strconv.Itoa(port)
	raddr, err := net.ResolveTCPAddr(network, target)
	if err != nil {
		return ch, fmt.Errorf("Fail to resolve %s: %v", target, err)
	}

	conn, err := net.DialTCP(network, nil, raddr)
	if err != nil {
		return ch, fmt.Errorf("Fail to dial %s: %v", raddr, err)
	}

	wg.Add(1)
	go func() {
		defer wg.Done()
		defer conn.Close()
		buf := make([]byte, 4)
		util.WriteBytes(conn, buf, util.NewMessage(util.Data, []byte("PUT "+name)))
		for data := range ch {
			util.WriteBytes(conn, buf, util.NewMessage(util.Data, data))
		}
		util.WriteBytes(conn, buf, util.NewMessage(util.CloseChannel, nil))
	}()

	return ch, nil
}
Example #2
0
func (rc *ReceiveChannel) receiveTopicFrom(target string) {
	// connect to a TCP server
	network := "tcp"
	raddr, err := net.ResolveTCPAddr(network, target)
	if err != nil {
		log.Printf("Fail to resolve %s:%v", target, err)
		return
	}

	// println("dial tcp", raddr.String())
	conn, err := net.DialTCP(network, nil, raddr)
	if err != nil {
		log.Printf("Fail to dial %s:%v", raddr, err)
		time.Sleep(time.Second)
		return
	}
	defer conn.Close()

	buf := make([]byte, 4)

	util.WriteBytes(conn, buf, util.NewMessage(util.Data, []byte("GET "+rc.name)))

	util.WriteUint64(conn, rc.offset)

	util.WriteBytes(conn, buf, util.NewMessage(util.Data, []byte("ok")))

	ticker := time.NewTicker(time.Millisecond * 1100)
	defer ticker.Stop()
	go func() {
		buf := make([]byte, 4)
		for range ticker.C {
			util.WriteBytes(conn, buf, util.NewMessage(util.Data, []byte("ok")))
			// print(".")
		}
	}()

	for {
		f, data, err := util.ReadBytes(conn, buf)
		if err == io.EOF {
			// print("recieve close chan2: eof")
			break
		}
		if err != nil {
			log.Printf("receive error:%v", err)
			continue
		}
		rc.offset += 4 + 1
		if f != util.Data {
			// print("recieve close chan1: ", string([]byte{byte(f)}))
			break
		}
		// println("receive raw data :", string(data.Bytes()))
		rc.offset += uint64(len(data.Data()))
		rc.Ch <- data.Data()
	}
	close(rc.Ch)
}
Example #3
0
func (as *AgentServer) handleWriteConnection(r io.Reader, name string) {
	as.name2StoreLock.Lock()
	ds, ok := as.name2Store[name]
	if !ok {
		s, err := store.NewLocalFileDataStore(as.dir, fmt.Sprintf("%s-%d", name, as.Port))
		if err != nil {
			log.Printf("Failed to create a queue on disk: %v", err)
			as.name2StoreLock.Unlock()
			return
		}
		as.name2Store[name] = NewLiveDataStore(s)
		ds = as.name2Store[name]

		//register stream
		go client.NewHeartBeater(name, as.Port, "localhost:8930").StartHeartBeat(ds.killHeartBeater)
	}
	as.name2StoreLock.Unlock()

	buf := make([]byte, 4)
	for {
		_, message, err := util.ReadBytes(r, buf)
		if err == io.EOF {
			// println("agent recv eof:", string(message.Bytes()))
			break
		}
		if err == nil {
			util.WriteBytes(ds.store, buf, message)
			// println("agent recv:", string(message.Bytes()))
		}
		if message.Flag() != util.Data {
			// println("finished writing", name)
			break
		}
	}
}
Example #4
0
func (as *AgentServer) handleLocalReadConnection(conn net.Conn, name string, offset int64) {
	as.name2StoreLock.Lock()
	ds, ok := as.name2Store[name]
	if !ok {
		s, err := store.NewLocalFileDataStore(as.dir, fmt.Sprintf("%s-%d", name, as.Port))
		if err != nil {
			// log.Printf("Failed to create queue on disk: %v", err)
			as.name2StoreLock.Unlock()
			return
		}
		as.name2Store[name] = NewLiveDataStore(s)
		ds = as.name2Store[name]
	}
	as.name2StoreLock.Unlock()

	closeSignal := make(chan bool, 1)

	go func() {
		buf := make([]byte, 4)
		for false {
			// println("wait for reader heartbeat")
			conn.SetReadDeadline(time.Now().Add(2500 * time.Millisecond))
			_, _, err := util.ReadBytes(conn, buf)
			if err != nil {
				fmt.Printf("connection is closed? (%v)\n", err)
				closeSignal <- true
				close(closeSignal)
				return
			}
		}
	}()

	buf := make([]byte, 4)

	// loop for every read
	for {
		_, err := ds.store.ReadAt(buf, offset)
		if err != nil {
			// connection is closed
			if err != io.EOF {
				log.Printf("Read size from %s offset %d: %v", name, offset, err)
			}
			// println("got problem reading", name, offset, err.Error())
			return
		}

		offset += 4
		size := util.BytesToUint32(buf)

		// println("reading", name, offset, "size:", size)

		messageBytes := make([]byte, size)
		_, err = ds.store.ReadAt(messageBytes, offset)
		if err != nil {
			// connection is closed
			if err != io.EOF {
				log.Printf("Read data from %s offset %d: %v", name, offset, err)
			}
			return
		}
		offset += int64(size)

		m := util.LoadMessage(messageBytes)
		// println(name, "sent:", len(messageBytes), ":", string(m.Data()))
		util.WriteBytes(conn, buf, m)

		if m.Flag() != util.Data {
			// println("Finished reading", name)
			break
		}
	}

}