RDF

(For information about my project, see here. Put shortly, it's about enabling Solr to index RDF data via drupal.)

Before starting the actual coding, even on prototypes, the basic options for implementing this will have to be discussed. At the moment, my mentors and I see the following three possibilities:

In Aarau — ­ Drupal Media Camp Schweiz 2009

Overview

This project is about adding RDF Support to the popular ApacheSolr module in the form of a Solr RDF contrib module. The module should be able to read an RDF class specification and automatically generate the necessary mapping to a Solr server, provide the capability to search resources with that type and also generate facets based on its properties. It would even be possible to build the existing Node search capabilites completely on top of this mechanism! But in any case you could also add arbitrary other types like users or taxonomy terms, or resources from other websites altogether.

I've just posted step-by-step instructions on how to use the Drupal 6.x RDF module to upgrade your Drupal site's RSS feeds for compatibility with RDF and the Semantic Web:

http://ar.to/2009/03/rdfizing-drupal-rss-feeds

As I don't do comments on my site, please feel free to discuss here.

DrupalCon DC 2009 featured a nice selection of RDF related sessions. 2 regular presentations served as introduction to those who were unfamiliar with the topic, or just wanted to refresh their mind with the latest happenings.

In http://drupal.org/node/395586 I suggest a way to create genealogies via cck and views. I am working on implementing it on a drupal site, but wondered if there is any input these groups can provide me with:

I would like to add that I plan on primarily using prepopulate in creating links for this, but I can see that some stuff will need some module code in order to be user friendly.

Right now there is a issue for getting token into core and one for getting some RDF into it. I wonder if makes sense to base the token patch upon the RDF stuff. So once we have some semantics attached to our objects, we can use them as a starting point for doing the token replacements.

The other way round, the RDF patch could learn from the tokens code - as the actual problem to solve is quite similar. The way the patch in #74 uses simple handlers to get tokens would make sense for RDF too. Then the token implementation can go and build upon that and reuse the handlers returning RDF string literals. Similarly, the approach described in #77 for doing actual token replacements could also be used for getting chunks of RDF for a bunch of objects.

Then apart from avoiding inventing the wheel twice, we could easily make both APIs consistent, so they can be used the same way.

I remember hearing talk about the need for a new database field to be added to Drupal core taxonomy.module's term_data table to stash the GUID/UUID/URI associated with a term. This was particularly relevant for sharing/importing/exporting taxonomies and using standard vocabularies. I suspect it also has relevance to RDF, but my comprehension is still a bit hazy on it.

OpenCalais calais.module adds a column 'guid' to the term_data table. I can't imagine that there would be any collision risks if other modules insert in this field as well for their own vocabularies.

Reading into the area of semantic web applications, rdf, owl, etc. let me wonder about the lack of information you can get of the current state of development in this area. There doesn't seem to be a wide range of applications using OWL or even RDF. Therefore I'd like to know, what range you use rdf, owl & co for? Especially, how do you/ can imagine to, use Drupal for fürther applications?

My current project

I'm interested in non-programmer tools that are available to help content creators "mark-up" their content for RDF (Resource Description Framework) discovery. We need good tools to describe free-form content that isn't already fielded in a database.

I am a big fan of FCKeditor (http://drupal.org/project/fckeditor), especially because it is so configurable. You can customize the fckstyles.xml file and add a new style like ...