Laravel - Broadcasting - Defining Authorization Callbacks

Next, we need to define the logic that will actually determine if the currently authenticated user can listen to a given channel. This is done in the routes/channels.php file that is included with your application. In this file, you may use the Broadcast::channel method to register channel authorization callbacks:

    Broadcast::channel('orders.{orderId}', function ($user, $orderId) {
        return $user->id === Order::findOrNew($orderId)->user_id;

The channel method accepts two arguments: the name of the channel and a callback which returns true or false indicating whether the user is authorized to listen on the channel.

All authorization callbacks receive the currently authenticated user as their first argument and any additional wildcard parameters as their subsequent arguments. In this example, we are using the {orderId} placeholder to indicate that the "ID" portion of the channel name is a wildcard.