Importing a feed with Zend_Feed_Reader is not
that much different to Zend_Feed. Feeds can
be imported from a string, file, URI or an instance of type
Zend_Feed_Abstract. Importing from a URI can
additionally utilise a HTTP Conditional GET
request. If importing fails, an exception will be raised. The end result will be an
object of type Zend_Feed_Reader_FeedInterface, the
core implementations of which are
Zend_Feed_Reader_Feed_Rss and
Zend_Feed_Reader_Feed_Atom
(Zend_Feed took all the short names!). Both
objects support multiple (all existing) versions of these broad feed
types.
In the following example, we import an RDF/RSS 1.0 feed and extract some basic information that can be saved to a database or elsewhere.
<?php
$feed = Zend_Feed_Reader::import('http://www.planet-php.net/rdf/');
$data = array(
'title' => $feed->getTitle(),
'link' => $feed->getLink(),
'dateModified' => $feed->getDateModified(),
'description' => $feed->getDescription(),
'language' => $feed->getLanguage(),
'entries' => array(),
);
foreach ($feed as $entry) {
$edata = array(
'title' => $entry->getTitle(),
'description' => $entry->getDescription(),
'dateModified' => $entry->getDateModified(),
'authors' => $entry->getAuthors(),
'link' => $entry->getLink(),
'content' => $entry->getContent()
);
$data['entries'][] = $edata;
}
The example above demonstrates
Zend_Feed_Reader's API, and it also
demonstrates some of its internal operation. In reality, the RDF
feed selected does not have any native date or author elements,
however it does utilise the Dublin Core 1.1 module which offers
namespaced creator and date elements.
Zend_Feed_Reader falls back on these and
similar options if no relevant native elements exist. If it
absolutely cannot find an alternative it will return NULL,
indicating the information could not be found in the feed. You
should note that classes implementing
Zend_Feed_Reader_FeedInterface also implement
the SPL Iterator and
Countable interfaces.
Feeds can also be imported from strings, files, and even objects of
type Zend_Feed_Abstract.
<?php
// from a URI
$feed = Zend_Feed_Reader::import('http://www.planet-php.net/rdf/');
// from a String
$feed = Zend_Feed_Reader::importString($feedXmlString);
// from a file
$feed = Zend_Feed_Reader::importFile('./feed.xml');
// from a Zend_Feed_Abstract object
$zfeed = Zend_Feed::import('http://www.planet-php.net/atom/');
$feed = Zend_Feed_Reader::importFeed($zfeed);