(Go) WebSocket Connect

Demonstrates how to establish a WebSocket connection. Once the connection is established, messages may be sent back-and-forth. Messages are sent in frames, where the last frame in the message is indicated by a "final" bit. A frame constitutes the entire message if the first frame sent has the "final" bit sent. (In most cases, you'll probably be sending single-frame messages.)

Chilkat Go Downloads Go Package for Windows, MacOS, Linux, Alpine Linux, Solaris

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    // --------------------------------------------------
    // A WebSocket connection begins life as an HTTP GET request containing a few special header fields,
    // such as "Upgrade: websocket".   

    // Your application will use the Chilkat Rest class to send the initial HTTP GET.  This allows you
    // to use the full capability of the Chilkat Rest class to customize the GET for any particular situation.
    // For example:
    // 
    //   - If custom HTTP request header fields must be added.
    //   - If authentication is required, such as OAuth2, OAuth1, Basic HTTP Auth, etc.
    //   - If HTTPS, SSH Tunneling, Proxies (HTTP or SOCKS), or other advanced connection or TLS features are required.
    // 

    rest := chilkat.NewRest()
    success := rest.Connect("someserver.com",80,false,false)
    if success != true {
        fmt.Println(rest.LastErrorText())
        rest.DisposeRest()
        return
    }

    ws := chilkat.NewWebSocket()

    // Tell the WebSocket to use this connection.
    success = ws.UseConnection(rest)
    if success != true {
        fmt.Println(ws.LastErrorText())
        rest.DisposeRest()
        ws.DisposeWebSocket()
        return
    }

    // Add the standard WebSocket open handshake headers that will be needed.
    // (This adds the required HTTP request headers to the rest object.)
    ws.AddClientHeaders()

    // Add any additional headers that might be desired.
    // Two common WebSocketSpecific headers are "Sec-WebSocket-Protocol" and "Origin".
    rest.AddHeader("Sec-WebSocket-Protocol","x-something")
    rest.AddHeader("Origin","http://someserver.com")

    // Do the open handshake.
    responseBody := rest.FullRequestNoBody("GET","/something")
    if rest.LastMethodSuccess() != true {
        fmt.Println(rest.LastErrorText())
        rest.DisposeRest()
        ws.DisposeWebSocket()
        return
    }

    // If successful, the HTTP response status code should be 101,
    // and the response body will be empty. (If it failed, we'll have a look
    // at the response body..)
    statusCode := rest.ResponseStatusCode()
    fmt.Println("Response status code: ", statusCode)

    if statusCode != 101 {
        fmt.Println(*responseBody)
        fmt.Println("-- Failed because of unexpected response status code.")
        rest.DisposeRest()
        ws.DisposeWebSocket()
        return
    }

    // We have the expected 101 response, so let's now validate the 
    // contents of the response, such as the value sent by the server in the
    // Sec-WebSocket-Accept header. 
    success = ws.ValidateServerHandshake()
    if success != true {
        fmt.Println(ws.LastErrorText())
        rest.DisposeRest()
        ws.DisposeWebSocket()
        return
    }

    fmt.Println("WebSocket connection successful.")

    // The application may now begin sending and receiving frames on the WebSocket connection.
    // (At this point, we're done with the rest object...)

    rest.DisposeRest()
    ws.DisposeWebSocket()