Leobard's blog

At the moment we need a SPARQL conformant interface to Sesame2, and as there is none I know of, the power of open source allows us to write one.


My first question is: did somebody already write a Servlet that does map Sesame2 servers to the SPARQL protocol?

At the moment sesame2 does not support full SPARQL querying, but it will soon. We don’t have to insist on SPARQL as query language, we can pass in SERQL queries and treat them like they were SPARQL, but we have to start with a conformant servlet 🙂

Then some longer questions I also asked on the Sesame developer mailinglist:

We think that a SPARQL protocol conformant HTTP servlet is most important for any use of Sesame2 and are willing to invest 10 hours a week into this, more precisely, a clever student worker. We hope to get this done until the end of September.

We would implement a SPARQL protocol conformat query server and a SPARQL protocol conformant query client (issue tracker) for the reading operations of a HTTPSail. For updates of the model, we would stick to the current implementation of the latest CVS of sesame2.

want to know what the sparql protocol is?

I understand that these are MANY questions, I tried to think of all the calamities we are going to face in the next months. And I expect that some hackers out there already handled half of these questions, so don’t hesitate to write me, or comment here, or to the sesame devel list.

* The org.openrdf.sesame.server.http.RepositoryServlet is not conformant to the SPARQL protocol,
as defined in the WSDL, or?
http://www.w3.org/TR/rdf-sparql-protocol/#query-bindings-http
the protocol described at org.openrdf.sesame.server.http.protocol.txt does not say anything about sparql

* If not, does anybody know how to generate stubs for the servlets automatically (so that they strictly conform to the protocol)?

* If not, we would examine the Jena / Joseki implementation, as it serves as reference implementation.

* When we implement a SPARQL conformat servlet – can we put it directly into the package org.openrdf.sesame.server.http.SparqlReadServlet, directly in the latest CVS, to have the best uptake and feedback possible?

* If yes, is there also a parser for query results, that can be used on the Client side HTTP sail to read results written by the server?

* What is the status of the HTTP Client? Did anybody do since we last mailed? if yes, please add comments to this ticket:
http://www.openrdf.org/issues/browse/SES-205

* Is the query string already part of the Query object? Jeen said this is a prerequisite for this hack. If not, Jeen: could you do this? This is such a core thing that I don’t want to touch it and for you its probably only 50 lines of code.
I mean the solution 1) suggested here:
http://www.openrdf.org/issues/browse/SES-205#action_10533

* Can Sesame2 serialize Query results according to the SPARQL protocol?
I see the QueryResultFormat.SPARQL which would indicate that.

* last but not least: any news about SPARQL query support?

* Do you have a debug environment to test the existing servlets from org.openrdf.sesame.server.http?

* Does the WebClient work? (the code looks SOOO COOL! spring rocks)
– I cannot find any code in the webclient project that actually *changes* triples… hm.

* When Sebastian starts hacking, whom can he jabber/icq for help?

Ok, who from the Semantic Web guys and girls is going to Burning Man this year?

I am going, and we are blogging here about that:

• http://burningman2006.blogspot.com/

I tried to find you guys by using search engines, but I am not witty enought to get the right results, so blogging and asking this question is probably ok for today.

Here is the story how I tried to find you:

This time I swoogled the semantic web to find out who lives near SFO, which indicates that they may go to burningman.

My first try was to go to swoogle.com, a very interesting website where you may lose hours during your office time. Then I found the search engine at swoogle.umbc.edu.

I tried to search for:

• ns:foaf SFO but this broke. Internal Server Error in /work/swoogle/www/swoogle/3.1/components/com_frontpage/writer.search.php on line 61
• perhaps not search documents, search ontologies instead. SFO – no results
• just entering francisco returned too much.
• refining to ns:foaf francisco, zero.
• at this point, I registered for an account at swoogle, perhaps then more. Hm, no.

Ok, perhaps the search syntax is wrong. Lets go to Intellidimension’s Semantic Web Search engine at www.semanticwebsearch.com.

• ah, they have a combobox where you can select foaf files. Lets do that and search for SFO.. Hm, one result, a substring match. woah, they do substrings.
• searching for “francisco” I get one foaf file seven times. It is a livejournal user, joey-francisco.
• ok, now fumbling around with the airport thingy, I tweaked it so that I can finally find Dan Brickley, as an example. this search for a foaf:person with nearest airport EDDG.
• btw: it also works when you search for “any resource”: search
• ok, now my SFO search. brought nothing.

ok, change of tactics: shoot straight at the target of burning man.

• semanticwebsearch for burningman. Brings some RSS feeds. Ok, that are bloggers. I need semweb bloggers though.
• perhaps some foaf person said something in interests or so? search, nothing.
• with “burning man” we get two livejournal users.

ok, lets see what the market leader does.

• google for burningman semantic web. 50.000 results. My own blog post on clothes is far on top, first page.
• hm, groucho marx said not to join a club that would accept you. So that high ranked blog entry of myself, hm. Ok, first ranked was a #rdfig scratchpad entry. But the nym user on #rdfig only pointed to a now dead website.
• I limit to 2006. limit to 2006, to get this years burners. My blog post again.
• Looking at the results, I find the blog of Peter Brown at http://www.blogsicle.net/

ok, so I didn’t hear of these guys before and I see that this use case is interesting. Anyway:

Ok, who from the Semantic Web guys and girls is going to Burning Man this year?

Gunnar invested much time in the last week to improve his gnowsis experience – adding features he (and everybody else) missed.

read his post on everything that is now available in the gnowsis SVN!

a tag-cloud

a tagging bookmarklet

synchronising two gnowsis installations

Bullocks!

I googled for movie ontologies and all I got was powerpoints.

In what world am I?

then I found this:

• http://139.91.183.30:9090/RDF/VRP/Examples/moviedatabase.rdf# – hey, are you serious? an IP address as namespace?
• and the IMDB mapping for RDF which luckily my office mate Gunnar Grimnes

please, God, put me into the parallel universe where people do indeed make the semantic web.

There is a congres on “Semantic Web und Wissenstechnologien” in Darmstadt at ZGDV on 19th October 2006.

There are many interesting people from Germany giving talks there, Benjamin Novack from the hacker side, Georg Lausen, Andreas Kupfer, Michael Stollberg from Innsbruck, Torsten Priebe from Capgemini Austria, Holger Rath from Empolis, Achim Steinacker from intelligent views, and Leo Sauermann from myself.

If you are a student of university, reduced conference fee for academics is 120€/290€.

• download the Flyer!