Sort multiple feeds by time and date

In SimplePie 1.0, we simplified the process of merging together multiple feeds, sorting them by date, and displaying them. This method allows you to do all of the normal SimplePie stuff without requiring you to do any array hacking or anything.

There are, however, two things to keep in mind about merging multiple feeds:

When you mash multiple feeds together, how do you know which feed title or favicon to use? You don't. So, the object that gets created when mashing feeds does not have any feed-level data.
You can still get at an individual item's parent feed data using the get_feed() method.
All feed items MUST have dates or else PHP will sort them to the top.

:!: If you're merging multiple feeds together, they need to all have dates for the items or else PHP will sort them to the top. This tutorial assumes that you're already familiar with using SimplePie, including looping through items.

Compatibility

Supported in SimplePie 1.0
Code in this tutorial should be compatible with PHP 4.3 or newer, and should not use PHP short tags, in order to support the largest number of PHP installations.

If all feeds have identical settings

<?php
// Include the SimplePie library
// For 1.0-1.2:
#require_once('simplepie.inc');
// For 1.3+:
require_once('autoloader.php');
 
// Create a new SimplePie object
$feed = new SimplePie();
 
// Instead of only passing in one feed url, we'll pass in an array of three
$feed->set_feed_url(array(
	'http://digg.com/rss/index.xml',
	'http://feeds.tuaw.com/weblogsinc/tuaw',
	'http://feeds.uneasysilence.com/uneasysilence/blog'
));
 
// We'll use favicon caching here (Optional)
$feed->set_favicon_handler('handler_image.php');
 
// Initialize the feed object
$feed->init();
 
// This will work if all of the feeds accept the same settings.
$feed->handle_content_type();
 
// Begin our XHTML markup
?><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
        "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">	
<head>
	<title>Awesome feeds</title>
	<link rel="stylesheet" href="../demo/for_the_demo/simplepie.css" type="text/css" media="screen" charset="utf-8" />
 
	<style type="text/css">
	h4.title {
		/* We're going to add some space next to the titles so we can fit the 16x16 favicon image. */
		background-color:transparent;
		background-repeat:no-repeat;
		background-position:0 1px;
		padding-left:20px;
	}
	</style>
</head>
<body>
	<div id="site">
 
		<?php if ($feed->error): ?>
		<p><?php echo $feed->error; ?></p>
		<?php endif; ?>
 
		<h1>Awesome feeds</h1>
 
		<?php foreach ($feed->get_items() as $item): ?>
 
		<div class="chunk">
 
			<?php /* Here, we'll use the $item->get_feed() method to gain access to the parent feed-level data for the specified item. */ ?>
			<h4 class="title" style="background-image:url(<?php $feed = $item->get_feed(); echo $feed->get_favicon(); ?>);"><a href="<?php echo $item->get_permalink(); ?>"><?php echo $item->get_title(); ?></a></h4>
 
			<?php echo $item->get_content(); ?>
 
			<p class="footnote">Source: <a href="<?php $feed = $item->get_feed(); echo $feed->get_permalink(); ?>"><?php $feed = $item->get_feed(); echo $feed->get_title(); ?></a> | <?php echo $item->get_date('j M Y | g:i a T'); ?></p>
 
		</div>
 
		<?php endforeach; ?>
 
	</div>
</body>
</html>

If feeds require separate, per-feed settings

<?php
// Include the SimplePie library
// For 1.0-1.2:
#require_once('simplepie.inc');
// For 1.3+:
require_once('autoloader.php');
 
// Create SimplePie objects for each feed, at least one with different settings
$digg = new SimplePie();
$digg->set_feed_url('http://digg.com/rss/index.xml');
 
$tuaw = new SimplePie();
$tuaw->set_feed_url('http://feeds.tuaw.com/weblogsinc/tuaw');
$tuaw->set_favicon_handler('handler_image.php');
$tuaw->init();
 
$uneasy = new SimplePie();
$uneasy->set_feed_url('http://feeds.uneasysilence.com/uneasysilence/blog');
 
// Let's merge them together.
$merged = SimplePie::merge_items(array($digg, $tuaw, $uneasy));
 
// Since we're using different feeds with different settings, let's set the header manually.
header('Content-type:text/html; charset=utf-8');
 
// Begin our XHTML markup
?><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
        "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">	
<head>
	<title>Awesome feeds</title>
	<link rel="stylesheet" href="../demo/for_the_demo/simplepie.css" type="text/css" media="screen" charset="utf-8" />
 
	<style type="text/css">
	h4.title {
		/* We're going to add some space next to the titles so we can fit the 16x16 favicon image. */
		background-color:transparent;
		background-repeat:no-repeat;
		background-position:0 1px;
		padding-left:20px;
	}
	</style>
</head>
<body>
	<div id="site">
 
		<h1>Awesome feeds</h1>
 
		<?php
		// Instead of calling $feed->get_items(), we'll use the $merged variable we created earlier.
		foreach ($merged as $item):
		?>
 
		<div class="chunk">
 
			<?php /* Here, we'll use the $item->get_feed() method to gain access to the parent feed-level data for the specified item. */ ?>
			<h4 class="title" style="background-image:url(<?php $feed = $item->get_feed(); echo $feed->get_favicon(); ?>);"><a href="<?php echo $item->get_permalink(); ?>"><?php echo $item->get_title(); ?></a></h4>
 
			<?php echo $item->get_content(); ?>
 
			<p class="footnote">Source: <a href="<?php $feed = $item->get_feed(); echo $feed->get_permalink(); ?>"><?php $feed = $item->get_feed(); echo $feed->get_title(); ?></a> | <?php echo $item->get_date('j M Y | g:i a T'); ?></p>
 
		</div>
 
		<?php endforeach; ?>
 
	</div>
</body>
</html>

tutorial/sort_multiple_feeds_by_time_and_date.txt · Last modified: 2012/07/09 01:54 by rmccue