Workshop - week 06

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Consuming an existing web feed

First you need to create a new controller, with just one "index" action.

In this action you simply create an instance of the Zend_Feed class, and call its "import" function to import a feed from a remote location (the BBC news website in this example). You then copy the content of the feed to an array, and pass the array to the view.

<?php

// application/controllers/FeedController.php

class FeedController extends Zend_Controller_Action 
{
    protected $_model;

    public function indexAction()
    {
        // Read remote feed
        try
        {
            $rss = Zend_Feed::import('http://newsrss.bbc.co.uk/rss/newsonline_uk_edition/front_page/rss.xml');
        } 
        catch (Zend_Feed_Exception $e)
        {
            // feed import failed
            echo "Exception caught importing feed: {$e->getMessage()}\n";
            exit;
        }

        // Initialize the channel data array
        $channel = array(
            'title'       => $rss->title(),
            'link'        => $rss->link(),
            'description' => $rss->description(),
            'items'       => array()
            );
        
        // Loop over each item and store relevant data
        foreach ($rss as $item) {
            $channel['items'][] = array(
                'title'       => $item->title(),
                'link'        => $item->link(),
                'description' => $item->description()
                );
        }

        // Pass to view
        $this->view->entries = $channel['items'];
    }

}

You also need to create a view for your new controller/action.

<!-- application/views/scripts/feed/index.hhtml -->

Feed Entries: <br />
<dl>
    <!-- Loop through the entries provided by the controller -->
    <? foreach ($this->entries as $entry): ?>
    <dt><?= $this->escape($entry['title']) ?></dt>
    <dd><?= $this->escape($entry['description']) ?></dd>
    <? endforeach ?>
</dl>

You can then simply access your consumed feed at the following URL: http://mi-linux.wlv.ac.uk/~0123456/zend/public/feed/ (please replace 0123456 by your own student numbeer!)

Note: For simplicity and clarity we are importing the feed in the controller, but a feed is an XML file, and as such could (should?) be considered as a data source. In line with MVC principles it would therefore be better practice to move the feed import code to a "model" file.

Producing your own web feed

Let's create a new "feed" action in out existing "Guestbook" controller.

    // application/controllers/GuestbookController.php

    public function feedAction()
    {
      // Change layout to blank.phtml (empty file)
      $this->_helper->layout->setLayout('blank');

      // Set feed values
      $array['title'] = 'Guestbook feed';
      $array['link'] = 'http://www.somewhere.com/';
      $array['description'] = 'This is guestbook feed';
      $array['charset'] = 'utf8';
      
      // Loop through db records and add feed items to array
      $model = $this->_getModel();
      foreach($model->fetchEntries() as $one_item)
      {
        $array['entries'][] = array(
          'title' => $one_item['email'],
          'link' => 'http://www.somewhere.com/123',
          'description' => $one_item['comment']
        );
      }
            
      // Import rss feed from array
      $feed = Zend_Feed::importArray($array, 'rss');

      // Send http headers and dump the feed
      $feed->send();
    }

To test your new "feed" action simply visit the following URL: http://mi-linux.wlv.ac.uk/~0123456/zend/public/guestbook/feed (please replace 0123456 by your own student numbeer!)