Java

WebSocket Connect through HTTP Proxy

See more WebSocket Examples

This example shows how to establish a WebSocket connection through an HTTP proxy server. Chilkat2 Java

import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.Rest;
import com.chilkatsoft.chilkat2.Socket;
import com.chilkatsoft.chilkat2.WebSocket;

public class ChilkatExample {

    public static void main(String[] args) {
        // 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 rest = new Rest();
        Socket socket = new Socket();

        // 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.
        boolean bTls = false;
        int port = 80;
        int maxWaitMs = 5000;
        try {
            socket.connect("some-websocket-server.com", port, bTls, maxWaitMs);
        } catch (ChilkatException e) {
            System.out.println("Connect Failure Error Code: " + socket.getConnectFailReason());
            System.out.println(e.getLastErrorText());
            return;
        }

        // Tell the Rest object to use the connected socket.
        try {
            rest.useConnection(socket, true);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        WebSocket ws = new WebSocket();

        // Tell the WebSocket to use this connection.
        String responseBody;
        try {
            ws.useConnection(rest);

            // 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");
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            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.getResponseStatusCode();
        System.out.println("Response status code: " + statusCode);

        if (statusCode != 101) {
            System.out.println(responseBody);
            System.out.println("-- 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.
        try {
            ws.validateServerHandshake();
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        System.out.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...)

        System.out.println("Success.");
    }
}