SocketServer.php

<?php

/**
 * Simple SocketServer that runs over the udp protocol. The run method takes a callable
 * which is called with the data received.
 *
 * @package Socket
 */
class SocketServer
{
    protected $hostname;
    protected $socket;

    /**
     * @param string $hostname A hostname like 127.0.0.1:9001
     */
    public function __construct(JsonFormatter $formatter, $hostname = '127.0.0.1:9001')
    {
        $this->formatter = $formatter;
        $this->hostname = $hostname;
    }

    /**
     * @param callable $callback Any valid callable
     */
    public function run($callback)
    {
        if (false == is_callable($callback)) {
            throw new \InvalidArgumentException('"' . $callback . '" is not a valid callable.');
        }

        $this->connect();

        while (false !== ($data = stream_socket_recvfrom($this->socket, 2048))) {
            $this->handle($callback, $data);
        }
    }

    /**
     * @param callable $callback
     * @param mixed $data
     */
    protected function handle($callback, $data)
    {
        $data = $this->formatter->format($data);

        call_user_func($callback, $data);
    }

    /**
     * @throws RuntimeException
     */
    protected function connect()
    {
        // This is needed as it will emit a warning instead and ruin my whole life!
        $this->socket = @stream_socket_server('udp://' . $this->hostname, $errno, $error, STREAM_SERVER_BIND);

        if (!$this->socket) {
            throw new \RuntimeException('Could not bind to "udp://' . $this->hostname . '".');
        }
    }
}

class JsonFormatter
{
    public function format($data)
    {
        return json_decode($data, true);
    }
}

(new SocketServer(new JsonFormatter))->run(function ($data) {
    var_dump($data);
});