Issues with Ratchet WAMP Component - php

Question

Brief Explanation...
I am trying to set up a Ratchet Web Socket server and am having a few issues. Here is what I am trying to achieve:
I have a counter on my website that indicates how many users have signed up to the website. I would like this counter to update whenever another users signs up to the website. Simples...
What I have Tried
I have only been using Ratchet for around 24 hours so my experience is extremely limited to say the least, but nevertheless, I have read the documentation thoroughly and I believe I am on the right track.
Here is my code:
push-server.php
// Autoload any required libraries
require(dirname(__DIR__).'/vendor/autoload.php');
// Initiate the loop and pusher
$loop = React\EventLoop\Factory::create();
$pusher = new _sockets\pusher;
// Listen for the web server to make a ZeroMQ push
$context = new React\ZMQ\Context($loop);
$pull = $context->getSocket(ZMQ::SOCKET_PULL);
// Binding to 127.0.0.1 means the only client that can connect is itself
$pull->bind('tcp://127.0.0.1:5555');
$pull->on('message', array($pusher,'message'));
// Set up the web socket server for the clients
$web_socket = new React\Socket\Server($loop);
// Binding to 0.0.0.0 means remotes can connect
$web_socket->listen(8080,'0.0.0.0');
$web_server = new Ratchet\Server\IoServer(
new Ratchet\Http\HttpServer(
new Ratchet\WebSocket\WsServer(
new Ratchet\Wamp\WampServer(
$pusher
)
)
),
$web_socket
);
// Run the loop
$loop->run();
pusher.php
namespace _sockets;
use Ratchet\ConnectionInterface;
use Ratchet\Wamp\WampServerInterface;
class pusher implements WampServerInterface {
/**
* A lookup of all the topics clients have subscribed to
*/
protected $subscribedTopics = array();
public function onSubscribe(ConnectionInterface $conn, $topic) {
$this->subscribedTopics[$topic->getId()] = $topic;
}
public function onUnSubscribe(ConnectionInterface $conn, $topic){
}
public function onOpen(ConnectionInterface $conn){
}
public function onClose(ConnectionInterface $conn){
}
public function onCall(ConnectionInterface $conn, $id, $topic, array $params){
}
public function onPublish(ConnectionInterface $conn, $topic, $event, array $exclude, array $eligible){
}
public function onError(ConnectionInterface $conn, \Exception $e){
}
public function message($data){
$data = json_decode($data,true);
// If the lookup topic object isn't set there is no one to publish to
if(!array_key_exists($data['category'],$this->subscribedTopics)) {
return;
}
$topic = $this->subscribedTopics[$data['category']];
// re-send the data to all the clients subscribed to that category
$topic->broadcast($data);
}
}
Snippet from Sign Up Script
// Push the sign up notice to all connections
$context = new ZMQContext();
$socket = $context->getSocket(ZMQ::SOCKET_PUSH);
$socket->connect("tcp://localhost:5555");
$array = array(
'category' => 'user_signed_up'
);
$socket->send(json_encode($array));
Snippet from JavaScript
// Connect to the website
var connection = new ab.Session('ws://MY_IP_ADDRESS:8080',
function(){
console.log('Connected to WebSocket');
connection.subscribe('user_signed_up',function(topic,data){
console.log(topic,data);
});
},
function(){
console.log('WebSocket Connection Closed');
},
{
'skipSubprotocolCheck': true
}
);
My Questions
All of the above works but before I proceed to thorough testing and production, I have a couple of questions:
Is the $persistent_id necessary with the getSocket method? I have read documentation but what is it actually used for? Do I need it, or, should I be using it?
I have been unable to find documentation on the on method for the ZMQ\Context class, has this been deprecated? Should I be using this or instead should I use recv?
How can I ensure my push-server.php is running all the time? Is there some sort of daemon tool I can use to ensure it is always running and will auto start if the server is rebooted?
Is it possible to attach the websocket to my domain instead of my IP Address? When I use my domain within the JavaScript, I receive a 400 Error...