Yahoo! Hacks

Program Yahoo! with XSLT

Transform Yahoo! Search Web Services responses into HTML with an XSLT stylesheet.

The Extensible Stylesheet Language (XSL) is a tag-based template system that can transform any XML document into any other text format, including other flavors of XML or, more commonly, HTML. Like a scripting language, XSL defines what data should go where on a page. You’ll still need to use a scripting language to perform the transformation from XML into HTML, and the entire process is encapsulated in the term XSL transformations or XSLT.

At first glance, an XSL stylesheet looks a lot like an HTML page, and it often contains HTML tags. But unlike HTML, each stylesheet must be valid XML and must contain a number of tags that describe how the XML should be processed. While an HTML document can have a few unclosed tags here and there and still display a web page, XSL is very strict and will fail if it’s not properly formed.

Responses from the Yahoo! Search Web Services are in XML and can be transformed directly into an HTML page with a bit of XSL.

The Code

Each stylesheet is organized into one or more templates that define how data from the source XML document should be arranged. The templates within a stylesheet contain a mix of XSL processing tags and HTML.

To try a transformation out, first create the stylesheet. Save the following XSL to a text file called yahoo_search.xsl:

<?xml version="1.0" encoding="UTF-8" ?> <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/ ...