Async Guzzle request with websocket endpoint

test-async-guzzle-websocket.php

<?php

declare(strict_types=1);

use GuzzleHttp\Client;
use GuzzleHttp\Handler\StreamHandler;
use GuzzleHttp\HandlerStack;
use Valtzu\WebSocketMiddleware\WebSocketMiddleware;
use Valtzu\WebSocketMiddleware\WebSocketStream;

require __DIR__ . '/vendor/autoload.php';

/**
 * Connect to WebSocket endpoints with Guzzle HTTP client
 * https://github.com/valtzu/guzzle-websocket-middleware
 *
 * Only works with PHP >8.2
 *
 * Not sure how we must use the method variable here.
 * It's weird to use the famous Guzzle HTTP client
 * (https://docs.guzzlephp.org/en/stable/)
 * for doing websocket connections...
 *
 */

try {
    $handlerStack = new HandlerStack(new StreamHandler());
    $handlerStack->push(new WebSocketMiddleware());

    $guzzle = new Client(['handler' => $handlerStack]);

    // Async call
    // TODO research what we can do with this payload array
    $payload = [];
    /** @var \GuzzleHttp\Psr7\Response $res */
    $res = $guzzle->requestAsync('GET', 'wss://nostr.sebastix.dev', $payload)
        ->then(
            function (\GuzzleHttp\Psr7\Response $e) {
                // Success callback.
                //print_r($e->getBody());
                return $e;
            },
            function (\Exception $exception) {
                // Error callback.
                echo 'Oh darn, we have a problem';
                throw $exception;
            },
        )
        ->wait();
    if ($res !== null) {
        // Get websocket connection.
        $ws = $res->getBody();
        if ($ws->isWritable()) {
            // TODO: do we need insert the stringified Nostr event here to write?
            $ws->write('What shall we write?');
            // This will return the message from the websocket endpoint (in our case it's the Nostr relay).
            $rr = $ws->read(100);
            echo $rr;
        }
        // Close websocket connection.
        $ws->close();
    }
    // TODO: read https://gorannikolovski.com/blog/asynchronous-and-concurrent-http-requests-in-php
    // TODO: https://docs.guzzlephp.org/en/stable/quickstart.html#concurrent-requests

    /**
     * We can use RelaySet as pool. In this pool (GuzzleHttp\Pool) requests are handled concurrent.
     * This pool will handle each RequestMessage as asynchronous request.
     * This means that each request is executed simultaneously (at the same time).
     * So for sending multiple requests concurrently we will use promises and asynchronous requests.
     */

} catch (Exception $e) {
    print $e->getMessage();
}