Golang中的套接字调试器

Question

Refer to the source code available in this link, I have to create a socket server which is communicating some GPRS devices. There is different models of that devices and not enough documentation for their handshake protocol.

Challenge: I need to be able to send custom responses to their requests and check their reaction.

My scenario: I edited this function ->

// Make a buffer to hold incoming data.
buf := make([]byte, 1024)
// Read the incoming connection into the buffer.
reqLen, err := conn.Read(buf)
if err != nil {
    fmt.Println("Error reading:", err.Error(), reqLen)
}
// Print to output
fmt.Println("
RECVD: " + string(buf));

text := "done!";
// Send a response back to person contacting us.
conn.Write([]byte("RESP: " + text))
// Close the connection when you're done with it.
conn.Close()

To this ->

// Make a buffer to hold incoming data.
buf := make([]byte, 1024)
// Read the incoming connection into the buffer.
reqLen, err := conn.Read(buf)
if err != nil {
    fmt.Println("Error reading:", err.Error(), reqLen)
}
// Print to output
fmt.Println("
RECVD: " + string(buf));

// Get response from user
fmt.Printf("RESP: ");

scanner := bufio.NewScanner(os.Stdin)
if scanner.Scan() {
    text := scanner.Text()
    fmt.Println("SENT: ", text)
    // Send a response back to person contacting us.
    conn.Write([]byte("RESP: " + text))
    // Close the connection when you're done with it.
    conn.Close()
}

I though that it should wait for my input to reply to the device. But my theory was really far from the reality.

Answer 1

you can use this function

func handleReq(conn net.Conn) {
    buf := make([]byte, 1024)
    reqLen, err := conn.Read(buf)
    if err != nil {
        fmt.Println("Error reading:", err.Error(), reqLen)
    }
    fmt.Println("
RECVD: " + string(buf))

    reader := bufio.NewReader(os.Stdin)
    fmt.Printf("RESP: ")
    text, _ := reader.ReadString('
')
    fmt.Println("SENT: ", text)
    conn.Write([]byte("RESP: " + text))
    conn.Close()
}

and you must wait for response on other side(persistent TCP).