protected function subscribeAtPubnub()
 {
     if (!$this->isSubscribed()) {
         return $this;
     }
     $this->pubnub = $this->context->getPubnub(array('publish_key' => 'foo', 'subscribe_key' => $this->subscription['deliveryMode']['subscriberKey']));
     //print 'PUBNUB object created' . PHP_EOL;
     $this->pubnub->subscribe($this->subscription['deliveryMode']['address'], array($this, 'notify'));
     //print 'PUBNUB subscription created' . PHP_EOL;
     return $this;
 }