Wednesday, September 24, 2008

Ubiquity, OWL-DL file accessibility and jOWL

If you are like me, and often browse to web in search of OWL-DL ontologies, then you have probably wished that there was an easier way to look at these files than just observing the raw OWL syntax.
I'm proud to announce a Ubiquity plugin that allows you to browse any OWL-DL file on the web with jOWL, the semantic javascript library I am developing, no matter where it is hosted.

I had been thinking on writing a Firefox plugin for quite some time for this purpose, even wrote some initial code, as this would be a great application for jOWL. But then came along the amazing Ubiquity.

About Ubiquity

Ubiquity is a Mozilla Experiment that is in two ways incredibly impressive:

  • It allows you to give natural language commands to the browser. Examples include 'map brussels', 'weather paris' or 'email this to {somebody}'

  • It allows you to basically mash up the entire web, avoiding the confinement of one domain only with it comes to looking at data.

The Mozilla blog post is quite instructive on what Ubiquity is about, I suggest you read it if you are not familiar with it yet.

About the jOWL Extension script to Ubiquity

As it turned out, writing the command was pretty straightforward. It is also very small in size (3KB only). Basically it feeds the OWL-DL document to a generic jOWL-Browser page I have set up. This browser page does all the heavy (jOWL) work, so even users unaware of javascript can use jOWL to browse OWL-DL files. Any issues and goodies are due to the jOWL library (which I continue to improve). The jOWL browser page contains the latest additions to the jOWL library (HTML templating and SPARQL-DL). I plan to write about and release a version update containing this functionality in the coming weeks.

Installing the functionality (Firefox Only)

  1. Get/Install the Ubiquity Natural Language commands extension from Mozilla

  2. Install the small (3 KB) script that enables the 'view_ontology' command by going to this page

  3. Go to a published OWL-DL file (examples below), open ubiquity and choose view_ontology

Tested Ontologies

The Ontologies must be expressed in OWL-DL.

If you encounter any issues, post to the Discussion group and I'll make sure to take them into account and update the functionality progressively. One thing I noticed already is that, if it is your first visit to the jOWL Browser page, the page can load empty. I'm looking into it, but the problem should be resolved by trying the same command once more on the OWL-DL file.

One more note, the viewer can also be used to peek at local OWL-DL files (for example if you are writing your own Ontology in OWL-DL syntax). Just load the file in Firefox and use the same Ubiquity command on it.

Hope you like it!