// 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
}
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)
}
