Tuesday, August 2, 2011

RDF Linking in Abiword

Another minor step forward in the quest to make the RDF facility in ODF more useful to document authors... Abiword can now create links to RDF and you can jump to these links in a similar manner to how bookmarks work. The upside to using RDF links over bookmarks is that you can associate meaning with the RDF links. So for example, the text "Barry" can be associated with his vcard and possibly normal work geolocation.

Making a new RDF link is just like inserting a bookmark:
And the "Go To..." dialog now offers RDF links as first class citizens. I did a little tweaking to this goto window while I was at it; moving things into a paged configuration and abstracting out some common code into utility functions.

On the API front, there are now STL like iterators for the RDF and that theme will be present in the query results engine and perhaps also in the arcsOut() API. Speaking of querying, the window for SPARQL is coming along. I'll start working on the actual query execution shortly. Notice that the RDF triples are shown with namespaces in effect so you get something more readable.

As I mentioned in my previous post, the purple links can be turned on and off to highlight parts of the document with RDF associated. Using a special menu item you can pull up the SPARQL query dialog with a preformed query to show just the RDF associated with the current cursor location.

I admit that some of this is quite low level, for example directly inspecting the triples for the cursor position. But full disclosure isn't a bad thing right? I syndicated this to planet KDE because Calligra handles RDF too. Hopefully posts about RDF are interesting to hackers regardless of the desktop platform :)


Egon Willighagen said...

This is neat! How can external (OWL) ontologies be plugged in?

monkeyiq said...

Thanks ;) I haven't looked at plugging in external RDF yet, though I imagine it would just link to the xml:id fragments in the same way as internal RDF (which is contained inside the ODT zip file).