The Protocol for Web Description Resources allows you to make statements about lots of resources at once - typically everything on a Web site. That sounds remarkably simple to do, I know, but, as they said when Beelzebub did his national service, the devil is in the detail*. POWDER transports RDF triples and attributes them to a named entity. To actually extract the triples you need to do some processing and have a specific 'candidate IRI' to describe. Within certain restrictions, it can be processed purely as XML but it can also be transformed into OWL so you can do full semantic processing.
Having chaired the working group (and the Incubator Group that preceded it), I am inexorably linked to POWDER for good or ill and this page is where I collect any related tools and news.
For chapter and verse on POWDER, including all the specs, namespace documents and XSLTs, see the POWDER Working Group home page.
- My POWDER Processor. A Perl-based processor that parses POWDER documents and stores their content in a MySQL database.
- Andrea Perego's 3P POWDER Processor. This is PHP-based and offers some functionality not offered by my processor, notably locating POWDER documents linked from documents. Andrea's processor always parses documetns in real time.
- Stasinos Konstantopoulos's SemPP - a Semantic POWDER Processing toolkit. This implementation pre-processes POWDER documents so that they can be injected into a standard RDF toolkit (SemPP uses Jena) and reasoning performed (SemPP uses Pellet). It is not a fully conformant POWDER Processor but ably demonstrates the use of POWDER data in a regular semantic framework.
Other POWDER Tools
- My POWDER Validator. It does not validate POWDER documents against the XML schema, rather it uses various Perl modules and XPath Queries to validate the data. I use the same code in the processor. 3P (Andrea Perego's POWDER processor) does validate POWDER documents against the schema.
- POWDER to POWDER-BASE transformation tool. This uses a subset of the validator to validate a POWDER document and return a POWDER-BASE transformation of it. This tool was created to do the same job as the POWDER to POWDER-BASE XSLT which works but uses XSLT 2 techniques that are not as widely supported as XSLT 1 (which the POWDER-BASE to POWDER-S XSLT uses). The script is documented on the validator page.
- POWDER Grouping Tester (A tool to help test and develop POWDER IRI sets)
Other tools/scripts I write that are not specific to POWDER are listed separately.
* I admit that I nicked that joke from Stephen Fry.