protected function _checkPubsubEnabled(Zend_Feed_Reader_FeedAbstract $feed)
 {
     if (!$feed->getHubs()) {
         return;
     }
     $hubs = $feed->getHubs();
     $sub = new Zend_Feed_Pubsubhubbub_Subscriber();
     $sub->setStorage(Doctrine_Core::getTable('Zfplanet_Model_Subscription'));
     $sub->addHubUrls($hubs);
     $sub->setTopicUrl($feed->getFeedLink());
     $sub->usePathParameter();
     $sub->setCallbackUrl($this->_getCallbackUri());
     $sub->subscribeAll();
 }

 /**
  * Constructor
  *
  * @param  DOMDocument $dom
  * @param  string $type
  */
 public function __construct(DomDocument $dom, $type = null)
 {
     parent::__construct($dom, $type);
     $atomClass = Zend_Feed_Reader::getPluginLoader()->getClassName('Atom_Feed');
     $this->_extensions['Atom_Feed'] = new $atomClass($dom, $this->_data['type'], $this->_xpath);
     foreach ($this->_extensions as $extension) {
         $extension->setXpathPrefix('/atom:feed');
     }
 }

 /**
  * Constructor
  *
  * @param  DOMDocument $dom
  * @param  string $type
  */
 public function __construct(DomDocument $dom, $type = null)
 {
     parent::__construct($dom, $type);
     $dublinCoreClass = Zend_Feed_Reader::getPluginLoader()->getClassName('DublinCore_Feed');
     $this->_extensions['DublinCore_Feed'] = new $dublinCoreClass($dom, $this->_data['type'], $this->_xpath);
     $atomClass = Zend_Feed_Reader::getPluginLoader()->getClassName('Atom_Feed');
     $this->_extensions['Atom_Feed'] = new $atomClass($dom, $this->_data['type'], $this->_xpath);
     if ($this->getType() !== Zend_Feed_Reader::TYPE_RSS_10 && $this->getType() !== Zend_Feed_Reader::TYPE_RSS_090) {
         $xpathPrefix = '/rss/channel';
     } else {
         $xpathPrefix = '/rdf:RDF/rss:channel';
     }
     foreach ($this->_extensions as $extension) {
         $extension->setXpathPrefix($xpathPrefix);
     }
 }