pusher.php

<?php
$pusher = new \Pusher(
    env('PUSHER_AUTH_KEY', null),
    env('PUSHER_APP_SECRET', null),
    env('PUSHER_APP_ID', null),
    $options
);
$data['message'] = 'Order ' . $order->id . ' was updated';
$pusher->trigger('order', 'updated', $data);

?>

The javascript
<script>
  const pusher = new Pusher(pusherAuthKey, {
      encrypted: true
  });

  const channel = pusher.subscribe('order');
  channel.bind('updated', this.getOrders)
</script>