Unicode C

WebSocket Connect through HTTP Proxy

See more WebSocket Examples

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

#include <C_CkRestW.h>
#include <C_CkSocketW.h>
#include <C_CkWebSocketW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkRestW rest;
    HCkSocketW socket;
    BOOL bTls;
    int port;
    int maxWaitMs;
    HCkWebSocketW ws;
    const wchar_t *responseBody;
    int statusCode;

    success = FALSE;

    // 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 = CkRestW_Create();
    socket = CkSocketW_Create();

    // Set the HTTP proxy domain or IP address, and port.
    CkSocketW_putHttpProxyHostname(socket,L"192.168.1.79");
    CkSocketW_putHttpProxyPort(socket,808);

    // Provide authentication to the HTTP proxy, if needed.
    CkSocketW_putHttpProxyUsername(socket,L"HTTP_PROXY_LOGIN");
    CkSocketW_putHttpProxyPassword(socket,L"HTTP_PROXY_PASSWORD");
    CkSocketW_putHttpProxyAuthMethod(socket,L"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.
    CkSocketW_putHttpProxyForHttp(socket,TRUE);

    // Connect to the websocket server through the HTTP proxy.
    bTls = FALSE;
    port = 80;
    maxWaitMs = 5000;
    success = CkSocketW_Connect(socket,L"some-websocket-server.com",port,bTls,maxWaitMs);
    if (success != TRUE) {
        wprintf(L"Connect Failure Error Code: %d\n",CkSocketW_getConnectFailReason(socket));
        wprintf(L"%s\n",CkSocketW_lastErrorText(socket));
        CkRestW_Dispose(rest);
        CkSocketW_Dispose(socket);
        return;
    }

    // Tell the Rest object to use the connected socket.
    success = CkRestW_UseConnection(rest,socket,TRUE);
    if (success != TRUE) {
        wprintf(L"%s\n",CkRestW_lastErrorText(rest));
        CkRestW_Dispose(rest);
        CkSocketW_Dispose(socket);
        return;
    }

    ws = CkWebSocketW_Create();

    // Tell the WebSocket to use this connection.
    success = CkWebSocketW_UseConnection(ws,rest);
    if (success != TRUE) {
        wprintf(L"%s\n",CkWebSocketW_lastErrorText(ws));
        CkRestW_Dispose(rest);
        CkSocketW_Dispose(socket);
        CkWebSocketW_Dispose(ws);
        return;
    }

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

    // Add any additional headers that might be desired.
    // Two common WebSocketSpecific headers are "Sec-WebSocket-Protocol" and "Origin".
    CkRestW_AddHeader(rest,L"Sec-WebSocket-Protocol",L"x-some-websocket-subprotocol");
    CkRestW_AddHeader(rest,L"Origin",L"http://some-websocket-server.com");

    // Do the open handshake.
    responseBody = CkRestW_fullRequestNoBody(rest,L"GET",L"/something");
    if (CkRestW_getLastMethodSuccess(rest) != TRUE) {
        wprintf(L"%s\n",CkRestW_lastErrorText(rest));
        CkRestW_Dispose(rest);
        CkSocketW_Dispose(socket);
        CkWebSocketW_Dispose(ws);
        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 = CkRestW_getResponseStatusCode(rest);
    wprintf(L"Response status code: %d\n",statusCode);

    if (statusCode != 101) {
        wprintf(L"%s\n",responseBody);
        wprintf(L"-- Failed because of unexpected response status code.\n");
        CkRestW_Dispose(rest);
        CkSocketW_Dispose(socket);
        CkWebSocketW_Dispose(ws);
        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 = CkWebSocketW_ValidateServerHandshake(ws);
    if (success != TRUE) {
        wprintf(L"%s\n",CkWebSocketW_lastErrorText(ws));
        CkRestW_Dispose(rest);
        CkSocketW_Dispose(socket);
        CkWebSocketW_Dispose(ws);
        return;
    }

    wprintf(L"WebSocket connection successful.\n");

    // 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...)

    wprintf(L"Success.\n");


    CkRestW_Dispose(rest);
    CkSocketW_Dispose(socket);
    CkWebSocketW_Dispose(ws);

    }