(C#) WebSocket Connect through HTTP Proxy

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

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//  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.
// 

Chilkat.Rest rest = new Chilkat.Rest();
Chilkat.Socket socket = new Chilkat.Socket();

//  Set the HTTP proxy domain or IP address, and port.
socket.HttpProxyHostname = "192.168.1.79";
socket.HttpProxyPort = 808;

//  Provide authentication to the HTTP proxy, if needed.
socket.HttpProxyUsername = "HTTP_PROXY_LOGIN";
socket.HttpProxyPassword = "HTTP_PROXY_PASSWORD";
socket.HttpProxyAuthMethod = "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.HttpProxyForHttp = true;

//  Connect to the websocket server through the HTTP proxy.
bool bTls = false;
int port = 80;
int maxWaitMs = 5000;
bool success = socket.Connect("some-websocket-server.com",port,bTls,maxWaitMs);
if (success != true) {
    Debug.WriteLine("Connect Failure Error Code: " + Convert.ToString(socket.ConnectFailReason));
    Debug.WriteLine(socket.LastErrorText);
    return;
}

//  Tell the Rest object to use the connected socket.
success = rest.UseConnection(socket,true);
if (success != true) {
    Debug.WriteLine(rest.LastErrorText);
    return;
}

Chilkat.WebSocket ws = new Chilkat.WebSocket();

//  Tell the WebSocket to use this connection.
success = ws.UseConnection(rest);
if (success != true) {
    Debug.WriteLine(ws.LastErrorText);
    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.
string responseBody = rest.FullRequestNoBody("GET","/something");
if (rest.LastMethodSuccess != true) {
    Debug.WriteLine(rest.LastErrorText);
    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..)
int statusCode = rest.ResponseStatusCode;
Debug.WriteLine("Response status code: " + Convert.ToString(statusCode));

if (statusCode != 101) {
    Debug.WriteLine(responseBody);
    Debug.WriteLine("-- Failed because of unexpected response status code.");
    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) {
    Debug.WriteLine(ws.LastErrorText);
    return;
}

Debug.WriteLine("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...)

Debug.WriteLine("Success.");