Transform XML in PHP
XML has now been around for quite a few years. If you are doing any type of web development it’s pretty hard to avoid XML. All RSS Feeds are really just XML documents that you access via a URL. For RSS, there are some well defined standard schemas (i.e., structured definitions) that the XML documents are created as.
RSS feeds are a common way of adding “self-updating” content to your web site. If you are using a platform like Wordpress then you can find some Wordpress plugins that make it quite easy to put content into your page or post from an RSS feed without any coding on your part. The downside, of course, is that you’re stuck with the format/layout that the plugin produces.
XSLT to the Rescue
XSLT is used to “transform” an XML document. With XSLT you can take an XML document and transform it into HTML, plain text, XML, and more. It’s a great way to turn an RSS Feed into a web page (or part of a web page) that is unique and fits your theme.
So, by now you’re probably wondering what it takes to actually transform XML using XSLT. The example I’m going to provide you is done using PHP. You can do this in almost any web development language, it’s just a matter of learning the proper syntax and APIs to use.
For my example I’m going to use the following RSS Feed:
http://www.NothingButZunes.com/zune-feed.xml
I’m going to show you how to use some very simple XSLT and the XML library in PHP to transform it into HTML that will look like this:
Top Selling Zunes, Zune Accessories, and More
Lists the top selling zune, zune media players, and zune accessories.
Zune Home A/V Pack
 |
Manufactured By: Zune Release Date: 2006-11-21 Rating:  , 47 ReviewsList Price: $99.99 Buy New (17): $21.71 Buy Used (2): $24.99 Buy now and save $78.28 |
Zune 80 GB Digital Media Player Black (2nd Generation)
 |
Manufactured By: Zune Release Date: 2007-11-13 Rating:  , 299 ReviewsList Price: $249.00 Buy New (10): $248.85 Buy Used (3): $223.97 Buy now and save $0.15 |
Zune Home A/V Pack
|
Manufactured By: Zune Release Date: 2006-11-21 Rating: , 47 ReviewsList Price: $99.99 Buy New (17): $21.71 Buy Used (2): $24.99 Buy now and save $78.28 |
Altec Lansing M604 Powered Audio System for Zune
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Manufactured By: Altec Lansing Technologies Rating: , 101 ReviewsList Price: $199.99 Buy New (3): $98.99 Buy Used (1): $79.00 Buy now and save $101.00 |
Zune Leather Case 80 GB
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Manufactured By: Zune Rating:  , 19 ReviewsList Price: $49.99 Buy New (14): $15.98 Buy Used (1): $23.94 Buy now and save $34.01 |
Belkin Sports Jacket Case with Armband for Zune 30 GB (Black)
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Manufactured By: Belkin Components Release Date: 2006-10-04 Rating: , 16 ReviewsList Price: $19.99 Buy New (4): $14.99 Buy Used (1): $8.64 Buy now and save $5.00 |
Unviersal Car Windshield Mount Holder for Htc 8525, 8125, Wing, Dash, Mda, Ppc-6800, Blackberry 8300 Curve, 8100 Pearl, 8800, 8830, Palm Treo 680, 750, 700w, Nokia N95, N75, N80, Lg Vx8500, Vx9900, Vx8350, Vx8600, Cu575, Audiovox, Motorola, Samsung, Sanyo, All Hp Ipaq, Nextel, Sony Ericsson W810, W580i, Sidekick, Apple Ipod Touch, Classic, Video, Iphone, Creative Zen, Microsoft Zune, Sandisk Sansa, Gps, PSP
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Manufactured By: Bargaincell Rating:  , 9 ReviewsList Price: $29.99 Buy New (1): $8.57 Buy now and save $21.42 |
Bluetooth Handsfree Fm Transmitter for Car Stereo Modulator 200 Channel / Ipod / Zune Car Kit-black with Built in Backnoise Cancelation Microphone AD2P Ready(Black)
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Manufactured By: Satechi Rating: , 27 ReviewsBuy New (1): $99.00 Buy now and save $30.99 |
JBuds Hi-Fi Noise-Reducing Ear Buds (Black)
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Manufactured By: JLab Audio Rating: , 676 ReviewsList Price: $49.95 Buy New (12): Too low to display Buy Used (1): $41.58 Buy now and save $32.62 |
Coby CVE92 Isolation Stereo Earphones
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Manufactured By: Coby Rating: , 143 ReviewsList Price: $19.99 Buy New (29): $4.13 Buy now and save $15.86 |
Digital Media Converter by DeskShare
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Manufactured By: DeskShare, Inc. Rating:  , 1 ReviewsList Price: $49.95 Buy New (1): $39.95 Buy now and save $10.00 |
Xilisoft Microsoft Zune DVD & Video Converter Suite
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Manufactured By: Xilisoft List Price: $45.00 |
How to Do Everything with Your Zune
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Manufactured By: McGraw-Hill Osborne Media Release Date: 2007-07-13 Rating: , 4 ReviewsList Price: $24.99 Buy New (1): $9.99 Buy now and save $15.00 |
Tinderbox
| [No Preview Image] | Manufactured By: Common Courage Press Rating: , 7 ReviewsList Price: $29.95 Buy Used (4): $6.77 |
Laptop Speakers - USB, Portable, Compact, Travel Speaker for PC and Mac - B-Flex 2 Hi-Fi Stereo USB Speaker (Black)
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Manufactured By: JLab Audio Rating: , 21 ReviewsList Price: $69.95 Buy New (1): $39.95 Buy now and save $30.00 |
White Travel Size Foldable Multimedia Speaker for iPod, iPod (video), iPod nano, iPod Photo, iPod Mini, and iPod Shuffle
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Manufactured By: Insten Rating: , 11 ReviewsList Price: $39.99 Buy New (5): $3.50 Buy Used (1): $2.99 Buy now and save $36.49 |
XML, XSLT, PHP
I’ve listed the PHP code below. The $xslt variable contains the text of the XSLT that is used when transforming the RSS Feed.
<?php
$xslt = '<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:fo="http://www.w3.org/1999/XSL/Format">
<xsl:output method="html" omit-xml-declaration="no"/>
<xsl:template match="/rss/channel">
<h1><a href="{link}"><xsl:value-of select="title"/></a></h1> <p><xsl:value-of select="description"/></p>
<xsl:for-each select="item">
<h2><a href="{link}"><xsl:value-of select="title"/></a></h2>
<xsl:value-of disable-output-escaping="yes" select="description"/>
</xsl:for-each>
</xsl:template>
</xsl:stylesheet>';
function Transform($xmlData, $xslText)
{
$output = "";
$CurVer = phpversion();
if (version_compare($CurVer, '5.0.0') < 0)
{
$xml = domxml_open_mem($xmlData);
$xsl = domxml_xslt_stylesheet($xslText);
$result = $xsl->process($xml);
$output = $result->dump_mem();
}
else
{
$xml = new DOMDocument();
$xml->loadXML($xmlData);
$xsl = new DOMDocument();
$xsl->loadXML($xslText);
$proc = new XSLTProcessor();
$proc->importStyleSheet($xsl);
$output = $proc->transformToXML($xml);
}
echo $output;
}
function ShowRssFeed($url, $xslText)
{
$ch = curl_init($url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_HEADER, 0);
$row = curl_exec($ch);
curl_close($ch);
if ($row == ”)
{
echo ‘
Data feed not available
‘;
}
else
{
file_put_contents(’zune.xml’, $row);
Transform($row, $xslText);
}
}
ShowRssFeed(’http://www.NothingButZunes.com/zune-feed.xml’, $xslt);
?>
