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Post details: Generating RDFa from RDF

2008-10-21

13:38:47, Categories: Semantic Web

Generating RDFa from RDF

Can you suggest tools or web services for generating RDFa content from RDF?

Extracting RDF statements from (X)HTML+RDFa is a common task and that’s what many RDFa tools do. An example of such service is the W3C RDFa distiller service by Ivan Herman.

What about a “RDFa fusion” tool which gets (X)HTML and RDF content as input and produces (X)HTML+RDFa?

In domain specific situations one can use templating for inserting bits of RDFa in relevant places of (X)HTML markup. An example is the FOAF/RDF to FOAF/RDFa converter by Michael Hausenblas.

But that will not work in a general case when the structure of (X)HTML document is not known in advance.

RDFa in XHTML is a W3C Recommendation [W3C Semantic Web Activity news]
Templating Microformats from RDF by Danny Ayers where I spotted a link to Michael’s FOAF/RDF to RDFa converter

3 comments

Comments, Pingbacks:

Comment from: Richard Cyganiak [Visitor]

· http://dowhatimean.net/

This is a hard problem, because RDF in general doesn't contain any layout information, but RDFa needs layout information because the RDF statements are embedded in HTML layout.

Rendering RDF without domain information usually doesn't produce very good results. Therefore, I wonder a bit how useful such a service would be.

Maybe you can explain why you want to do this in the first place.

Permalink 2008-10-21 @ 21:17

Comment from: captsolo [Member]

I am talking about a situation when we already have HTML and RDF, and want to fuse them together by using RDFa.

An example situation is FOAF and SIOC data which many sites currently expose as external metadata. It might take a bit before all these sites convert to RDFa but it would be good if services which can consume RDFa (e.g., SearchMonkey) could make use of this data right away.

Can you not encode arbitrary RDF as HTML+RDFa? Assuming that humans are only concerned with what is visible and machines are only concerned with statements extracted from the document (visibility of which is not a requirement as such) is there any "stakeholder" who cares if RDF statements are associated with a particular DOM node?

P.S. I am not talking here about a UI for visualizing RDF which may not have a good generic solution. This post is just about using a web page as a carrier of RDF data for consumption by RDFa-aware applications.

Permalink 2008-10-21 @ 22:12

Comment from: Christoph Lange [Visitor]

· http://kwarc.info/clange/

I think that's very interesting if the XHTML is generated from some semantic source. A related case that makes me interested in this (and that made me retrieve this page via Google) is the processing of semantic markup. In our setting, we have documents in a semantic markup language and want to do several things with them:

presenting them to humans (i.e. as XHTML)
extracting RDF structures from them (for queries)

We have implementations for (1) and (2) but are now starting to combine them. For active documents, which offer interactive services to the user who is browsing them, we need semantics in the XHTML rendered by (1), and an obvious approach is to embed this semantics as RDFa (see the JOBAD project for details). As, in our case, both the XHTML and the RDF are generated from the same source, and our implementations of (1) and (2) are technically similar (both done in XSLT), it is easily possible to combine them.

Permalink 2008-11-12 @ 17:33