(Go) WebSocket Connect through HTTP Proxy

This example shows how to establish a WebSocket connection through an HTTP proxy server.

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.

    // --------------------------------------------------
    // This example borrows the code from the REST using HTTP Proxy example.
    // We first use the Chilkat Socket object to establish a connection to the WebSocket server through an HTTP proxy.
    // Next, the Rest object uses the Socket object for its connection.
    // Finally, the WebSocket object uses the Rest object for its connection.  
    // 

    rest := chilkat.NewRest()
    socket := chilkat.NewSocket()

    // Set the HTTP proxy domain or IP address, and port.
    socket.SetHttpProxyHostname("192.168.1.79")
    socket.SetHttpProxyPort(808)

    // Provide authentication to the HTTP proxy, if needed.
    socket.SetHttpProxyUsername("HTTP_PROXY_LOGIN")
    socket.SetHttpProxyPassword("HTTP_PROXY_PASSWORD")
    socket.SetHttpProxyAuthMethod("Basic")

    // Indicate that HTTP requests (i.e. the WebSocket opening handshake) will be sent over the socket.
    // This is important for how the HTTP proxy connection is established.
    socket.SetHttpProxyForHttp(true)

    // Connect to the websocket server through the HTTP proxy.
    bTls := false
    port := 80
    maxWaitMs := 5000
    success := socket.Connect("some-websocket-server.com",port,bTls,maxWaitMs)
    if success != true {
        fmt.Println("Connect Failure Error Code: ", socket.ConnectFailReason())
        fmt.Println(socket.LastErrorText())
        rest.DisposeRest()
        socket.DisposeSocket()
        return
    }

    // Tell the Rest object to use the connected socket.
    success = rest.UseConnection(socket,true)
    if success != true {
        fmt.Println(rest.LastErrorText())
        rest.DisposeRest()
        socket.DisposeSocket()
        return
    }

    ws := chilkat.NewWebSocket()

    // Tell the WebSocket to use this connection.
    success = ws.UseConnection(rest)
    if success != true {
        fmt.Println(ws.LastErrorText())
        rest.DisposeRest()
        socket.DisposeSocket()
        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-some-websocket-subprotocol")
    rest.AddHeader("Origin","http://some-websocket-server.com")

    // Do the open handshake.
    responseBody := rest.FullRequestNoBody("GET","/something")
    if rest.LastMethodSuccess() != true {
        fmt.Println(rest.LastErrorText())
        rest.DisposeRest()
        socket.DisposeSocket()
        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()
        socket.DisposeSocket()
        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()
        socket.DisposeSocket()
        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 and socket objects...)

    fmt.Println("Success.")

    rest.DisposeRest()
    socket.DisposeSocket()
    ws.DisposeWebSocket()