GRDDL

From GetSemantic

GRDDL stands for Gleaning Resource Descriptions from the Definition of Languages - it is a protocol which allows people to describe the semantics of a document through an external stylesheet which a GRDDL processor picks up and uses to automatically translate an XHTML document in to RDF. GRDDL stylesheets exist for most major microformats.

Contents 1 How to implement GRDDL for your format 2 Tips 3 GRDDL processors 4 Specifications 5 Worth reading

[edit] How to implement GRDDL for your format

• Put together an XHTML page which describes the format
• Add the stylesheet as a link element in the head of the XHTML file
• In the stylesheet, provide a transformation from XHTML (or XML - or schema?) in to RDF/XML.
• For each document that contains embedded semantics, simply add the URL of the XHTML page at the top. GRDDL processors should then be able to process it automatically.

[edit] Tips

• The easiest way to extract data from XHTML classnames is to use the following format:
  • contains(concat(' ', @class, ' '), ' vcard ') - where 'vcard' is the class name you are looking for

[edit] GRDDL processors

• RAP - RDF API for PHP
• Jena GRDDL Reader

[edit] Specifications

• GRDDL specification

[edit] Worth reading

• GRDDL Primer
• GRDDL Working Group at W3C
• Wikipedia
• Bridging XHTML, XML and RDF with GRDDL Dominique Hazaël-Massieux (W3C), at XTech 2005
• Microformats in context - Uche Ogbuji