func serverHandleConnection(s *Server, conn io.ReadWriteCloser, clientAddr string, workersCh chan struct{}) {
    defer s.stopWg.Done()

    if s.OnConnect != nil {
        newConn, err := s.OnConnect(clientAddr, conn)
        if err != nil {
            s.LogError("gorpc.Server: [%s]->[%s]. OnConnect error: [%s]", clientAddr, s.Addr, err)
            conn.Close()
            return
        }
        conn = newConn
    }

    var enabledCompression bool
    var err error
    var stopping atomic.Value

    zChan := make(chan bool, 1)
    go func() {
        var buf [1]byte
        if _, err = conn.Read(buf[:]); err != nil {
            if stopping.Load() == nil {
                s.LogError("gorpc.Server: [%s]->[%s]. Error when reading handshake from client: [%s]", clientAddr, s.Addr, err)
            }
        }
        zChan <- (buf[0] != 0)
    }()
    select {
    case enabledCompression = <-zChan: // 第一個(gè)標(biāo)志位 代表被壓縮
        if err != nil {
            conn.Close()
            return
        }
    case <-s.serverStopChan:
        stopping.Store(true)
        conn.Close()
        return
    case <-time.After(10 * time.Second):
        s.LogError("gorpc.Server: [%s]->[%s]. Cannot obtain handshake from client during 10s", clientAddr, s.Addr)
        conn.Close()
        return
    }

    responsesChan := make(chan *serverMessage, s.PendingResponses)
    stopChan := make(chan struct{})

    readerDone := make(chan struct{})
    go serverReader(s, conn, clientAddr, responsesChan, stopChan, readerDone, enabledCompression, workersCh)

    writerDone := make(chan struct{})
    go serverWriter(s, conn, clientAddr, responsesChan, stopChan, writerDone, enabledCompression)

    select {
    case <-readerDone:
        close(stopChan)
        conn.Close()
        <-writerDone
    case <-writerDone:
        close(stopChan)
        conn.Close()
        <-readerDone
    case <-s.serverStopChan:
        close(stopChan)
        conn.Close()
        <-readerDone
        <-writerDone
    }
}

• OnConnect，像中間件一樣對(duì)原本的clientAddr和conn進(jìn)行處理弓熏，可以記錄日志，甚至可以封裝糠睡。
• zChan用于通知消息是否被壓縮挽鞠。
• 啟動(dòng)讀協(xié)程和寫協(xié)程去讀取消息。讀寫協(xié)程之間的交互靠responsesChan狈孔，停止靠stopCh通信同時(shí)通知兩個(gè)協(xié)程信认。
• 調(diào)用函數(shù)被 讀寫協(xié)程readDone和writerDone通知，如果讀寫協(xié)程崩潰則通知調(diào)用函數(shù)均抽。進(jìn)而同時(shí)通知stopChan關(guān)閉另一個(gè)
• 如果serverStopChan（上層停止調(diào)用）通知狮杨，則直接close（stopChan）通知讀寫協(xié)程退出。

寫的很巧妙到忽，像詩(shī)一樣