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GRDDL extraction *to* RDFa

From: Ben Adida <ben@mit.edu>
Date: Thu, 07 Sep 2006 20:08:07 -0400
Message-ID: <4500B467.6070207@mit.edu>
To: public-grddl-wg <public-grddl-wg@w3.org>


Hi all,

I've been tasked with describing my driving use case for joining this
WG. I will call this use case the "GRDDL extract to XHTML" use case.

When GRDDL is used to extract triples from some XML document, its output
is usually RDF/XML or N3, or some other such "raw" triple format. In
some cases, this transformation discards important human-parseable
information: everything that style and layout bring to the table. This
use case explains how it might be useful to have GRDDL preserve the
"human" aspect of a document during the transformation.

Consider Alice, who likes to attend various conferences, talks, or other
gatherings of social groups in her area. These groups publish their
calendars in various HTML-based formats: microformats, eRDF, RDFa, or
some home-grown way to express calendar information. If these calendars
use GRDDL, Alice can easily add all of these events to her own Google
Calendar.

However, Alice doesn't want to add *all* events to her calendar. She
wants to pick and choose which events to attend. She browses to her
local theater's upcoming events page, scrolls down to the one event she
likes, and then copies and pastes this event to her calendar.

To enable this copy-and-paste, Alice's browser supports a default
RDF-in-HTML embedding scheme, RDFa. Then, GRDDL hooks in the page
indicate how to transform this homegrown XHTML into XHTML+RDFa, while
preserving the style and layout of the page.

Thus, Alice's RDFa-aware browser can perform the transform even before
rendering the XHTML. Then, the rendered XHTML+RDFa can provide
copy-and-paste functionality via, for example, right-clicking on an
event right in the rendered XHTML+RDFa.

For these features to work, we need to specify a GRDDL transform that
can output XHTML+RDFa as its serialization of RDF. Ideally, this would
be indicated right when the GRDDL hook is declared, so that a browser
knows ahead of time what the GRDDL transform will output.

-Ben

PS: I used Alice instead of Jane because the use case seems different
than the existing Jane use case... that said, I'm certainly open to
integrating this into another use case.
Received on Friday, 8 September 2006 00:08:20 GMT

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