The last few weeks have been pretty eventful for the semantic web in Drupal.
Lin Clark and I wrote a couple of articles for the IBM developerWorks explaining what it is possible to achieve with Drupal 7 and the recent developments in core and contrib. They are pretty detailed and will be useful materials for newbies willing to learn how to use the Semantic Web technologies in Drupal 7:
- The Semantic Web, Linked Data and Drupal, Part 1: Expose your data using RDF
- The Semantic Web, Linked Data and Drupal, Part 2: Combine linked datasets with Drupal 7 and SPARQL Views
The RDF contributed module for Drupal 7 is now called RDF Extensions and has been moved to a new project namespace: http://drupal.org/project/rdfx. The main reason for this change is some recurring feedback from DrupalCon Chicago and other events where people were confused between the RDF module in core and the RDF module in contrib. From now on, when you hear about the RDF module it will be the core module (enabled by default when you download Drupal 7), and when you hear about RDF Extensions (or RDFx for short), it will be the contributed project. If you were subscribed to the RDF project issues, make sure to subscribe to the new RDF Extensions project issue queue.
I also posted my masters thesis on my blog, with a retrospective on the whole initiative to integrate RDF in Drupal 7 core. It includes a few pages on the design of RDF and RDFa in Drupal 7 core as it was back in 2009 (which is still pretty accurate).
Finally, a code sprint was organized last week-end in Cambridge, where Bryan Hirsch, Alexander Dorsk, Miles Worthington (remote) and myself gathered to work on some of the issues of RDF Extensions, SPARQL and the very promising SPARQL Views project. At the same time, Lin was hacking on SPARQL Views and finding ways to use it with the VIVO project at the VIVO hackathon in Gainesville, Florida.
We’ll try to organize code sprints every now and then (with hopefully earlier notices). In the meantime if you want to give a hand in the issue queues, Lin and I will be happy to help you get started.
Comments
Thanks for your wok
Just wanted to say thanks for all of the work that you and Lin and others have done on making the Semantic Web technologies more user friendly for mainstream developers. No doubt you have heard it before, but this is so vital to have the vision of the Semantic Web come to fruition sooner rather than later. I'm working with SPARQL Views right now coupled with DBpedia and your IBM write-up and while I have run into some roadblocks, the potential for this is tremendous. Keep up the good work.
Thanks for the updates and your work!
We've decided to upgrade our beta site to Drupal 7 after reading both IBM articles. Cool stuff. Thanks to you and Lin for your work on this. After years of studying semantic web technologies and standards, using it in the "real world" context of Drupal development is a welcome task!
Module RDFx
I have a question that no longer appears on the tab of RDF nodes on the latest updates RDFx module. In previous versions if you had the tab. Someone can help me with information about this topic.
yes, we removed the RDF tab
yes, we removed the RDF tab which was not wanted by some people. See the release notes for the alpha2 version which explains it in a bit more details how you can work around that RDF tab.
Thanks
Thanks for the information
About RDF output using RDFx (7.x-2.x) module
First of all I apologize for my English. I have some questions about rdfx module and the rdf output when i browse to node/id.rdf. I have created a content type called News_Article with fields title,body,tags,image,type of news, published from and from which resource came from. I have done all the rdf mappings for these fields and i have imported my own external rdf vocabulary. So, when I am browsing node/id.rdf i do not get mappings such as image and basic relationship maps such as sioc:has_creator ( but i get this relation when browse node/id.xml or node/id.json) and in none of these formats relasionships such as sioc:reply_of for comments. e.g the only map which i get for comments is the sioc:num_replies but i want to get the creator of the comment, the title and also the body of the comment. Am i doing something wrong?i m trying to understand how Restfull web services and Entity Api working because i think there is the solution of my problem. Can anyone could help me? Thanks in advance!
Hi Tsare, The .xml and .json
Hi Tsare,
The .xml and .json outputs are generated by the Entity API and the RESTws module. Only the .rdf is generated by RDFx. RDFx will only output fields which have been mapped to an RDF property via the RDF UI, while the .xml will output all the fields known to the entity API. I've created an issue to allow all properties without mappings to be included in the RDF output.
You can get the data for each comment at comment/1.rdf. unfortunately, there is currently no way to get that data included in node/1.rdf, see the issue http://drupal.org/node/1237296 and in particular my comment #1. Any help on this is very welcome!