test1/public/drupal-8.3.1/vendor/zendframework/zend-feed/doc/book/intro.md

Introduction

Zend\Feed provides functionality for consuming RSS and Atom feeds. It provides a natural syntax for accessing elements of feeds, feed attributes, and entry attributes. Zend\Feed also has extensive support for modifying feed and entry structure with the same natural syntax, and turning the result back into XML. In the future, this modification support could provide support for the Atom Publishing Protocol.

Zend\Feed consists of Zend\Feed\Reader for reading RSS and Atom feeds, Zend\Feed\Writer for writing RSS and Atom feeds, and Zend\Feed\PubSubHubbub for working with Hub servers. Furthermore, both Zend\Feed\Reader and Zend\Feed\Writer support extensions which allows for working with additional data in feeds, not covered in the core API but used in conjunction with RSS and Atom feeds.

In the example below, we demonstrate a simple use case of retrieving an RSS feed and saving relevant portions of the feed data to a simple PHP array, which could then be used for printing the data, storing to a database, etc.

RSS optional properties

Many RSS feeds have different channel and item properties available. The RSS specification provides for many optional properties, so be aware of this when writing code to work with RSS data. Zend\Feed supports all optional properties of the core RSS and Atom specifications.

Reading RSS Feed Data

// Fetch the latest Slashdot headlines
try {
    $slashdotRss =
        Zend\Feed\Reader\Reader::import('http://rss.slashdot.org/Slashdot/slashdot');
} catch (Zend\Feed\Reader\Exception\RuntimeException $e) {
    // feed import failed
    echo "Exception caught importing feed: {$e->getMessage()}\n";
    exit;
}

// Initialize the channel/feed data array
$channel = [
    'title'       => $slashdotRss->getTitle(),
    'link'        => $slashdotRss->getLink(),
    'description' => $slashdotRss->getDescription(),
    'items'       => [],
];

// Loop over each channel item/entry and store relevant data for each
foreach ($slashdotRss as $item) {
    $channel['items'][] = [
        'title'       => $item->getTitle(),
        'link'        => $item->getLink(),
        'description' => $item->getDescription(),
    ];
}

Your $channel array now contains the basic meta-information for the RSS channel and all items that it contained. The process is identical for Atom feeds since Zend\Feed provides a common feed API; i.e. all getters and setters are the same regardless of feed format.