Category Archives: XML Prague

XML Prague 2015 Impressions

XML Prague 2015 is over and I’m now at the Prague airport, waiting to board a plane. The weather is beautiful–from where I am, it looks like spring–and I’m on a high after my XML holiday.

Some impressions, in no particular order:

  • Being a participant rather than a speaker was a good thing, this year. I’ve been able to relax and focus on listening to the presentations without having to worry about slides or demos.
  • The presentations, for the most part, were great. There were some that weren’t spot on for me, but things like JSON in an RDFa context (Alex Milowski’s talk) were far more interesting than I’d have thought. I still don’t like JSON but Alex’s talk was interesting, entertaining and actually very cool.
  • Hans Jurgen Rennau suggested in his talk node searches in XPath preceding actual node construction, an extremely useful idea presented in his usual well-thought and rational manner. I liked this one a lot, and it is a suitable continuation of his XQuery Topic Tools concept first presented at Balisage last year.
  • Michael Kay started and ended the conference. The first talk of the conference was about XSLT parallel processing and the last was an update on the XSD, XSLT, XPath and XQuery specs work at W3C. Michael’s presentations are always interesting and always well presented. It is fititng that he is the foremost veteran speaker of the conference, having presented at every XML Prague since it started.
  • Norm Walsh talked (almost as fast as Alex Milowski; no wonder he finds the time for the W3C work, XML Calabash, his day job and, presumably, some free time doing photography and such) about progress on XInclude 1.1 and the eagerly anticipated XProc 2.0. Very interesting.

I’ll probably write more later. Time to board a plane.

XML Prague 2015

I finally got an approval from my boss to attend XML Prague 2015 and registered for it the other day. I’m not presenting this time around, just listening and learning, and looking very much forward to it.

On Reflection

Having reread my recent post on HTML5, I suppose I’d better stress the fact that it was never meant to be a commentary on HTML5 itself. It was a rant, something that happened because of the attitudes I think have increased in tandem with HTML5’s growing popularity. I really don’t know enough HTML5 to have an informed opinion beyond what I see suggested and discussed about it that is related to markup in general. My comments should be read in that light.

Take the addition of document semantics in HTML5 as a case in point. For example, the article and section tags are welcomed additions, as are, in my humble opinion, the fairly minor redefinitions of the em and strong semantics. And there’s some important work being done in the area of extensible semantics for the web (see, for example, Robin Berjon’s XML Prague paper, Distributed Extensibility: Finally Done Right? and the Web Components web page on best practices), which turned out to be a heated topic at Balisage this year because quite a few of its participants are, like me, grumpy old men defending their own turf.

These are steps in the right direction, because they move away from the presentational horror that is the “old” HTML and to a more semantic web. Semantics is about meaning, and meaning is now being added to the web rather than simply empty but oh-so-cool visuals. I should add that some very cool visuals are being added, too, but in, and please pardon the joke, a meaningful way.

But, and maybe this is just me, it’s when those steps are being heralded as original and unique, never thought of before or at least never done right, when history and past (and working) solutions are ignored or misinterpreted because they are part of a standard (XML or even SGML) that is regarded as failed, when I react. Google’s Dominic Denicola provided a case in point when he held a controversial presentation on the subject called Non-Extensible Markup Language at Balisage; unfortunately, only the abstract seems to be available at their website.

That grumpy old men thing, above, is meant as a joke, of course, but I imagine there to be some truth in it. Part of the HTML5 crowd will certainly see it that way because they are trying to solve a very practical problem using a very pragmatic standard. HTML5 is, in part, about keeping old things working while adding new features, and it seems to do the job well. Having to listen to some older markup geeks argue about what XML was actually designed to do must seem to be as being utterly beside the point.

So, what to do? Well, I think it’s largely about education, both for the newer guys to read up on the historical stuff, and the older guys to try to understand why HTML5 is happening the way it is, and then attempting to meet halfway because I’m pretty sure it will benefit both.

Me, I’m in the midst of the reading up phase, and HTML5 – The Missing Manual is an important part of that.

I Should Probably…

Following this year’s Balisage conference, I should probably do a rewrite and update of the whitepaper I presented. It’s on my list of things to do.

On the other hand, I should do an eXist implementation of the version handling system I suggested in that paper. It’s also on my list of things to do.

But then again, I still have to finish my ProXist implementation, the one I presented at XML Prague. It is (you guessed it) on my list.

I have lots of good (well, I think so) ideas first presented at XML conferences, many of which deserve (well, I think so) to live beyond them. After all, a lot of work goes into the papers and the presentations, so shouldn’t I follow up on them more?

My version handling system, for example, should be easy enough to do in eXist. It doesn’t require a revolution, it doesn’t require me to learn how to code in Java, it should be enough to spend a couple of nights writing XQueries and XSLT to produce a usable first version.

ProXist is both simpler and more difficult to finish, but on the other hand, the basic application is already out there and works. It’s a question of rewriting it to be easier for others to test, which basically means redoing it as a standard eXist app.

Yet, instead of doing something about either of them, here I am, writing this blog post. It’s conference procrastination taken to yet another level.

And the next XML Prague deadline is coming up fast.

Linux Ready for the Desktop and All That

My recent XML Prague presentation ran from a Linux partition, the first time in a while I’ve used Linux for presenting anything. The reasoning was simple; I’d developed the accompanying demo on Linux, on a server on localhost, so it would be much easier to just write a presentation in Open Office than to move the demo to something else.

It wasn’t.

I’d fixed every bug in the demo, styled my web pages in an aesthetically pleasing manner (well, for me), and carefully prepared an XML Prague presentation project in oXygen with only the files I would need to show, making sure that they’d fit without scrolling when projected in a lower resolution. I’d bookmarked the important code, and I’d folded everything else. My demo was in great shape.

What I didn’t do beforehand (even though I actually meant to) was to test my Linux laptop in dual screen mode, mirroring the laptop screen to an external monitor using that lower projector resolution. That, of course, was what failed.

My talk was immediately after a coffee break so I figured I’d hook up my laptop immediately after the last talk before the break and test all this. How hard could it be?

Well, no mirroring in that lower resolution. Mirroring in a higher one (the laptop’s native resolution) was possible but of course, the projector wouldn’t work in that resolution. They usually don’t. Dual screen mode, outputting two different screens, didn’t work because I wouldn’t be able to see on my laptop’s screen what was being projected for the audience. I tested pretty much every setting there was but to no avail.

And then the (Gnome) window manager decided it couldn’t take the abuse any longer and crashed.

I rebooted into KDE, hoping it would fare better, but all I got for my troubles was another crash. Not the same software, mind, but something or the other in KDE. I hadn’t really tried anything very dramatic, I’d simply changed the display modes a few times.

So I rebooted again and accepted my faith, booting into Gnome and using the dual screen mode where I’d be flying blind unless twisting my head all the way back like that poor girl in The Exorcist, trying to run the demo from the laptop’s touchpad in front of me while hurting my neck to see the results on the large screen behind and above me.

If you’ve watched the conference video (second day, about 7 or 8 hours into the file), you now know why.

My laptop is not particularly fancy or modern. It’s a 3-yo Thinkpad with an Nvidia Optimus graphics card, the kind that includes what was then a high-end Nvidia card and a low-end Intel card, the idea being that you use the former for the graphics-intensive stuff while reserving the latter for the 2D desktop stuff. It still doesn’t work properly in Linux so I only use an Nvidia only mode. It’s not something I blame the Linux developers for–the Optimus is proprietary and thus not something easily handled in open source–but it is what it is and quite common.

But other than that, there is nothing very special about my laptop. It just works, mostly. Well, it should.

So is Linux ready for the desktop yet?

This Year’s XML Prague…

…was fabulous. It always is, don’t get me wrong, but this one was the best yet. It’s all on video at the conference website, which, all things considered, is a pretty decent substitute for being otherwise engaged, but Prague this time of year is the XML capital of Europe and the place to be.

For one thing, I think I finally actually understand some of the streaming part of the up-and-coming XSLT 3.0 spec, thanks to Abel Braaksma and Michael Kay, who both presented papers on the subject.

John Lumley presented a paper on lessons learned when finalising a standard library for XSLT/XPath extensions to manipulate binary data, a brilliant talk.

George Bina showed oXygen on mobile devices with the crowd cheering his every swipe of the iPad screen, in what was probably one of the most memorable demos ever at XML Prague.

And there was me, lastly (literally; I was the last scheduled speaker, right before a concluding interactive talk led by Robin Berjon), showing my ProXist demo. It all went surprisingly well, except for a slight problem with Linux and Gnome.

You should have been there.

Oh, and…

…most of the ProX stuff is available at Github. Not the eXist web pages, yet, but that’s because I’m still experimenting with them and there’s some work left. There’s the Balisage demo, and there’s the basic ProXist stuff, with pipelines and XQueries and such, and there’s the authoring environment (with Relax NG schema, FO, etc), but no instructions on how to get any of it to run, yet.

I have a test app running locally, a little something that is about as simple as I can make it, but since I am not a web developer (I’m a markup geek), the HTML is awkward, the CSS nonexistent apart from the default eXist stuff, and the XQueries somewhat painful. I do think it’s going to be pretty cool, though, and look forward to presenting it at XML Prague.

ProXist and My XML Prague Paper

I recently submitted the final version of my XML Prague whitepaper about my eXist implementation of ProX, called ProXist (with apologies for the tacky name). While I’m generally pleased with the paper, the actual demo implementation I am going to present at the conference is not quite finished yet and I wish I had another week to fill in the missing parts.

Most of the ProXist stuff works but there are still some dots to connect. For example, something that currently occupies the philosophical part of my brain has to do with how to run the ProX wrapper process, the one that configures the child process that actually does stuff to the input. ProX, so far, has been very much about automation and about things happening behind the scenes, and so I have aimed for as few end user steps as possible.

My Balisage ProX demo was a simple wrapper pipeline that did what it did in one go. Everything was fitted inside that pipeline: selecting the input, configuring the process that is to be applied to the input in an XForm, postprocessing the configured process and converting it to a script that will run the child process, running the child process, saving the results. Everything.

But the other day, while working on the eXist version and toying with its web application development IDE, it dawned on me that there doesn’t have to be a single unified wrapper process. If its components are presented on a web page and every one of them includes logic to check if the information from a required step is available or not (for example, a simple check to confirm that an input has been chosen before the process can be configured), they don’t have to be explicitly connected.

The web page that presents the components (mainly, selecting input and configuring the process to be applied on the input) then becomes an implicit wrapper. The user reads the page and the presentation order and the input checks are enough. There is no longer a need a unified wrapper process.

Now, you may think this is obvious, and I have to admit that it now seems obvious to me, too. But I sometimes find it to move from one mindset (for example, that automation bit I mentioned, above) to another (such as the situation at hand, the actual environment I implement things in) as easily as I would like. If this is because I’m getting older or if it’s who I am, I don’t know. In this particular case, I was so convinced that the unified wrapper was the way to go that it got in the way of a better solution.

At least I think it’s a better solution. If it isn’t, hopefully I can change my mind again and in time.

See you at XML Prague.