PHP Requires Chilkat v11.0.0+

WebSocket through SSH Tunnel

See more WebSocket Examples

This example shows how to establish a WebSocket connection through an SSH tunnel. The WebSocket protocol communications will be encapsulated within an SSH tunnel. Chilkat2 PHP

<?php

use Chilkat2\Rest;
use Chilkat2\Socket;
use Chilkat2\WebSocket;

// 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 through SSH Tunnel example.
// We first use the Chilkat Socket object to establish a connection to the WebSocket server through an SSH Tunnel.
// Next, the Rest object uses the Socket object for its connection.
// Finally, the WebSocket object uses the Rest object for its connection.
//
// Hopefully the flexibility of this architecture is easy to see.  All of the HTTP functionality of the Rest object,
// such as HTTP authentication, custom headers, etc. is available to the WebSocket.  Likewise, all of the advanced functionality
// of the Socket object is in turn available to the Rest object.

// The high-level steps for accomplishing the task of running the WebSocket protocol through an SSH accomplished as follows:
// 1) Create the SSH tunnel using Chilkat Socket.
// 2) Open a port-forwarding channel (to the WebSocket server) within the tunnel.
// 2) Tell Rest to use the Socket object.
// 3) Tell WebSocket to use the Rest object.

$tunnel = new Socket();

$sshHostname = 'sftp.example.com';
$sshPort = 22;

// Connect to an SSH server and establish the SSH tunnel:
try {
    $tunnel->SshOpenTunnel($sshHostname, $sshPort);

    // Authenticate with the SSH server via a login/password
    // or with a public key.
    // This example demonstrates SSH password authentication.
    $tunnel->SshAuthenticatePw('mySshLogin', 'mySshPassword');

    //  OK, the SSH tunnel is setup.  Now open a channel within the tunnel.

    $bTls = true;
    $port = 443;
    $maxWaitMs = 5000;

    // This returns a socket object that is a single channel within the SSH tunnel.
    // The SSH channel is our logical port-forwarded connection through the SSH tunnel.
    // Note: This example establishes a TLS connection to the target WebSocket server.
    // (The TLS protocol will run on the logical channel within the SSH tunnel.)
    // Your application can just as easily make a non-TLS connection by changing the arguments
    // passed to SshNewChannel.
    $channel = new Socket();
    $tunnel->SshNewChannel('some-websocket-server.com', $port, $bTls, $maxWaitMs, $channel);

    // Create a REST object and tell it to use the SSH channel.
    // This connection is a TLS running on an SSH channel through an SSH tunnel.
    // In other words, TLS is wrapped within the SSH tunnel.
    $rest = new Rest();
    $rest->UseConnection($channel, false);

    // Finally, tell our WebSocket object to use the Rest object..
    $ws = new WebSocket();

    // Tell the WebSocket to use this connection.
    $ws->UseConnection($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 (\Chilkat2\Exception $e) {
    echo $e->getMessage(), "\n";
    exit;
}

// 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;
echo 'Response status code: ', $statusCode, "\n";

if ($statusCode != 101) {
    echo $responseBody, "\n";
    echo "-- Failed because of unexpected response status code.\n";
    exit;
}

// 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 (\Chilkat2\Exception $e) {
    echo $e->getMessage(), "\n";
    exit;
}

echo "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 object...)