Processing Linked Web Data with XSLT

he Semantic Web is a grand vision for increasing the power of the web through better expression and management of context. Semantic Web developers are building a framework to open up and connect organized information, which takes advantage of many popular developments on the web, such as the success of Wikipedia, Creative Commons-licensed publishing on sites like Flickr, and various blogs. A portion of this framework is the Linking Open Data (LOD) community initiative (seeded by the W3C Semantic Web Education and Outreach group). A goal of LOD is to weave together separate collections of open data using deep linking and RDF (Resource Description Framework) representations.

The hallmark of LOD is to make it easy for web developers to create and process compatible data. Utilizing LOD calls for a broad war chest of tools and techniques that cover the diverse expertise of Web developers. One popular tool for processing data on the web is XSLT (Extensible Stylesheet Language Transformations), building on the growth of XML as a data format on the web. XSLT is not a general-purpose programming language—so it is limited in its uses—including LOD processing. However, XSLT is very useful to handle auxiliary roles in such processing that involves transforming XML. This article explores specialized areas for the use of XSLT 1.0 in LOD processing. The focus is on XSLT 1.0 (XSLT 2.0 does offer more for LOD processing, but it is far more complex and much less used by the community). XSLT 1.0 has more processors than 2.0 and the EXSLT set of community extensions, which has strong support in Firefox 3.0, provides facilities that bring it close to the power of XSLT 2.0.