exchange/app/Events/RateUpdated.php

<?php

namespace App\Events;

use Illuminate\Broadcasting\Channel;
use Illuminate\Queue\SerializesModels;
use Illuminate\Broadcasting\PrivateChannel;
use Illuminate\Broadcasting\PresenceChannel;
use Illuminate\Foundation\Events\Dispatchable;
use Illuminate\Broadcasting\InteractsWithSockets;
use Illuminate\Contracts\Broadcasting\ShouldBroadcast;
use App\Rate;

class RateUpdated implements ShouldBroadcast
{
    use Dispatchable, InteractsWithSockets, SerializesModels;

    public $rate;

    /**
     * Create a new event instance.
     *
     * @return void
     */
    public function __construct(Rate $rate)
    {
        $this->rate  = $rate;
    }

    /**
     * Get the channels the event should broadcast on.
     *
     * @return \Illuminate\Broadcasting\Channel|array
     */
    public function broadcastOn()
    {
        return new Channel('rate-updated');
        //return new PrivateChannel('rate-updated');
    }

    public function broadcastWith() {
        return [
          'rate' => $this->rate,
        ];
      }

}