protected function channelName()
    {
        if (method_exists($this->notifiable, 'receivesBroadcastNotificationsOn')) {
            return $this->notifiable->receivesBroadcastNotificationsOn($this->notification);
        }

        $class = str_replace('\\', '.', get_class($this->notifiable));

        return $class.'.'.$this->notifiable->getKey();
    }