Technical Ramblings

Earlier today, on the OpenID mailing list, I was asked to supply Perl code to look for PPDs in FOAF docs and return some basic props on the user who owned the FOAF file. My Perl skills have long since fallen by the wayside, but I was able to put together something in Python which seems to me to work pretty good.

ppd.py is a FOAF parser using xml.dom.minidom to look for a PPD, and parse out a couple basic forms of the Personal Profile Document, for cases in which you can’t bring a full RDF parser to bear on the situation. (I know that the question of when this arises has been argued a million times, but an RDF parser is an extra dependency that some projects simply have no interest in bringing on.)

This parses two basic forms of PPD: one in which the foaf:maker is identified by an rdf:nodeID=”nodename”, or one in which the foaf:maker is identified as an rdf:resource=”#nodename” coupled with a rdf:ID=”nodename”.

This hasn’t been fully tested: it was mostly done as a quick proof of concept that people could expand on. I’ve tested it on the nodeID case, and tested that if it can’t find an appropriate PPD, it falls back (against LiveJournal files). I’m not sure how python-esque my code is, but it does seem to work, which was my primary concern.

As usual, this code is designed to be used at the command line as “python ppd.py http://crschmidt.net/foaf.rdf”, or imported as a module, after which you can run ppd.get_person(“http://crschmidt.net/foaf.rdf”).

Thoughts on the method? Will this work with a sufficiently constrained FOAF doc?

I’ve been doing some work with FOAFNaut, SVG, and other related technologies lately. For the most part, the changes in and of themselves are too small to track in a weblog format, but I did build myself a little tool to store recent updates to crschmidt.net last night, so I could share them. crschmidt.net site updates has an HTML view, as well as an RSS 1.0 and RSS 2.0 view, and is used to display information on the front page on what has changed recently.

Today, I spent a big chunk of my afternoon playing with julie alongside DanC. He asked if I planned on implementing SPARQL in the bot any time soon (which I do, as soon as a Redland release supporting the turtle format for SPARQL queries comes out). We also talked about GRDDL support, and some other related things. He offered some interesting files which I added to the database, teaching julie more about W3C proceedings and allowing for some more interesting queries in that respect. I need to start keeping track of my todolist for julie so that I can get organized in the freetime I have to do something about the state she’s in. I’m really starting to think another refactoring may be in order: although I received a pretty gigantic patch at one point, I still really haven’t “thrown one away” yet.

I also decided to install trac earlier today for some reason, something that was reinforced when I was asked to start a wiki foaf FOAFNaut internals as I was playing with it. You can check out the listing of projects I have here, which will grow as time continues, because I’m going to be moving more and more of my stuff into Subversion and more and more of what’s in Subversion to trac. It’s really nifty software, and I’m looking forward to playing with it. Who knows, it might shove a few more people into getting involved in my current projects. It’s got everything I need but have been too lazy to install in one place: wiki, bug tracking, source viewing, revision… quite nice, really.

Other than that, not much going on: Keep an eye on the site updates as I continue to do more little changes in and around crschmidt.net to my various projects.

A while ago I did a really crappy survey of how many people were using the various forms of “name” properties in the FOAF schema. I say “Crappy” becuase it was incomplete and generated via RDQL queries, which was a really silly way to do things, now that I know how to actually use a few of the Redland API calls. So, since I’m bored and working on a wrapper for a variety of Redland stuff, I figured I’d look at it again.

The model in question is the model for Julie, an IRC based interface to a Redland store. She contains about 2.3 megatriples, in a MySQL backed storage.

Total foaf:Persons: 129,932
Total statements using foaf:name as a predicate: 5549
Total statements using foaf:givenname as a predicate: 5363
Total statements using foaf:firstName as a predicate: 874
Total statements using foaf:family_name as a predicate: 117
Total statements using foaf:surname as a predicate: 6314
Total statements using foaf:nick as a predicate: 120529

Keep in mind that a large chunk of this data is spidered from LiveJournal, so the results are most likely going to be extremely biased to that case, which has no use of any name properties other than foaf:nick.

Nothing all that impressive, really, but interesting as far as statistics go nonetheless.

So, a long time ago, I posted about how I planned to update the FOAF that LiveJournal spits out to become more friendly, since I really didn’t know anything about RDF at all when I was first creating the format. So, I wanted to do some updates, to match things that I had discussed with members of the FOAF community over time.

However, I got a real job, lost my free time, blah blah blah, these things happen. The patch has sat around in various incarnations for at least 6 months, probably longer. Recently, someone asked me what had happened to it, and I responded that I had gotten tired of pushing for changes to FOAF, and given up. He said he had time to spare on pushing people, so I cleaned up my patch, and posted about it – a detailed rundown of the changes the patch makes, for evaluation by the community.

Since the community involved is larger than LiveJournal, I’m here to encourage absolutely anyone who might have an interest or knowledge in the arena to read through the explanation or the patch, and let me know what they think. I really would love to see this happen, but like I said, I’m not going to fight for it anymore: it took a lot of hard work to get the previous FOAF patch accepted, and I just don’t have the energy or free time to do that again. So, this one is going to depend on community feedback and demonstration of interest. If you think that LiveJournal’s FOAF data might be suboptimal, say something about it. That entry is a great place to comment and discuss. Open a dialouge with developers about what you’d like to see, because if enough people want to see it, someone may actually push it in.

I posted recently about Zeroconf, which allows for automated service discovery. One aspect of this which has already been exploited is the ability to have a local network of presence information, something like what iChat does to announce users who are online. However, it also passes along some simple FOAF information with it. I can’t remember who wrote the tool. If I recall correctly, it was shellac/Damien… ah, here we go. foaffinger.

Small HTTP server combined with zeroconf shares data.

Now, to expand this out a bit… now that I’m starting to know how to deal with Python a bit better, I might be able to do something with pyzeroconf and pyrple. I’d probably want to learn something about graphics too… wxPython requires an install. Are there any “built in” GUIs for Python? I don’t think so.

Anyway, local FOAF browsing of full data rather than just a subset would be nice. Not too hard, I don’t think, since Python makes almost everything simple. Of course, there is the problem that there’s no one that I share my network with… 😉

Ah well, I do have 2 macs, 2 linux boxes, and 2 windows laptops in the house now. (Wow! An even split. Nifty.) I can try it out somehow or another.

I’m kind of rambling. Usually I’d reserve this for noets, but I wanted a tie in from the Zeroconf post I just made.