Consuming a WebSocket API inside synchronous code

BluzelleService.php

<?php

namespace App;

use React\EventLoop\Factory;
use React\Socket\Connector as SocketConnector;
use Ratchet\Client\Connector as ClientConnector;
use Clue\React\Block;

class BluzelleService
{
    public $uri;
    public $uuid;

    public function __construct($uri = "ws://127.0.0.1:8100", $uuid = "80174b53-2dda-49f1-9d6a-6a780d4cceca")
    {
        $this->uri = $uri;
        $this->uuid = $uuid;
    }

    // Read the value of at a key,
    public function read($key = "myKey")
    {
        // Promises run on an event loop
        $loop = Factory::create();
        $reactConnector = new SocketConnector($loop, [
            'dns' => '8.8.8.8',
            'timeout' => 10
        ]);

        // Instantiate the Websocket client
        $connector = new ClientConnector($loop, $reactConnector);

        $result = "";
        // We have to get the result back out the nested callback
        // so we use by-ref variable $result to take it back out
        $promise = $connector($this->uri)->then(function ($conn) use (&$result, $key) {
            $read = [
                "bzn-api" => "crud",
                "cmd" => "read",
                "data" => [
                  "key" => $key,
                ],
                "db-uuid" => $this->uuid,
                "request-id"=> 1
              ];
            // send the message read from key
            $conn->send(json_encode($read));

            // setup the callback to read the result
            $conn->on('message', function ($msg) use (&$result, $conn) {
                $result = (string) $msg;
                $conn->close();
            });
        });
        // Clue\React\Block to wait for the above async code to run.
        Block\sleep(0.1, $loop);
        // The reason we can't just use the promise result is that
        // the promise resolves into a connection, not the actual result I want.
        Block\await($promise, $loop);
        return $result;
    }
}