Lost BoyA journal of no fixed aims or direction, by Leigh Dodds

Elliotte Harold has published a nice introduction to XForms in Firefox on IBM developerWorks. In the conclusion he notes that:
Client-side XForms processing won’t be possible for public-facing sites until XForms is more widely deployed in browsers. However, that doesn’t mean you can’t deploy it on your intranet today. If you’re already using Firefox (and if you aren’t, you should be), all that’s required is a simple plug-in. After that’s installed, you can take full advantage of XForms’ power, speed, and flexibility.
I’d agree with this whole-heartedly. I wrote and deployed a little XForms application just before Christmas and it was a very painless exercise indeed.
Over the past few years we’ve rolled out an number of RESTful XML based APIs internally. We’ve also toyed with different ways to build tools to manage systems using these APIs, including using Java Swing desktop tools, simple HTML forms, etc. Mainly we’ve been trying for a while to find a sweet spot between ease of implementation and a reasonably good user experience.
Recently I’d been toying with a Javascript library to one of our REST interfaces based around the Prototype library. It was fun if occasionally frustrating banging my head against Javascript. However it wasn’t finished and I needed to quickly roll out some forms for managing some key data. So I took another look at XForms. I’d researched it a few years ago and had rejected it because of the lack of browser support and the different ways that the plugins required you to deploy the forms.
As almost everyone internal has gravitated towards Firefox cross-browser support isn’t a strong requirement so I went ahead and built the system using XForms. It was a very satisfying experience: the syntax is easy to get to grips with, and its possible to create some fairly slick AJAX style forms with a minimum of fuss. And more fun that messing with Javascript.
So for us at least XForms does seem to hit a sweet spot for rapid tools development, particularly as we already have a lot of existing XML interfaces. In fact the exercise highlighted a few flaws in our interfaces (e.g. delivering correct mime types, under use of “hypermedia” to link between resources in some areas) so was a good learning exercise in its own right.
It would be nice to see some slicker custom controls for different data types though. I think AJAX and client-side scripting still corners the market on slick dynamic UIs, and will do for some time. But for sheer ease of use, and getting things done, XForms gets the thumbs up from me.

This is the second part of my look at XMP. This time I’m focusing on the potential for using XMP as the metadata format for OpenDocument (ODF).
This is part of a broader discussion to help define the future direction for the ODF metadata format, one proposal on the table is to use RDF, via a constrained RDF/XML syntax. There’s a wiki available for discussing this issue, particularly how to map existing metadata to RDF.
At least some of the impetus for exploring richer metadata support has come from the bibliographic sub-project which aims to build-in support for bibliography management into OpenOffice 3.0.
RDF is a good fit for the flexible storage and formatting requirements that arise from bibliographic metadata. As XMP is an RDF profile its worthy of consideration, and in fact this is the proposal behind Alan Lilich’s posting to the OpenDocument TC member list. Lilich’s discussion document frames the rest of this posting.

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I’ve been taking a look at XMP as I’ve been considering different ways to “enrich” content. Embedding metadata is one option and XMP aims to fulfill the role of a metadata format suitable for embedding in a diverse range of media formats.
It’s also under discussion as way to embed metadata in the OpenDocument format. The alternatives available in that quarter have been under discussion in various circles for some time. Bruce D’Arcus points to the latest entry to that discussion in his recent “OpenDocument and XMP” posting.
I thought I’d write up some notes on XMP in general and contribute some thoughts towards that debate. This is the first of two postings on this topic.

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Ken North just posted this email to XML-DEV drawing attention to a presentation by Daniela Florescu titled Declarative XML Processing with XQuery — Re-evaluating the Big Picture (Warning: PDF). It makes for interesting reading.
In the presentation, Florescu argues that XML is in a growth crisis and that there’s a need for more architectural work to tie together components of the XML landscape ranging from XQuery and XSLT through to RDF and OWL. Florescu believes that XML is about more than syntax and will in fact become the key model for information, not just bits on a wire. In short Florescu believes that XML has yet to achieve its full potential and to do that some further work needs to be done.
The presentation is worth reading in its entirety. The majority of the presentation does focus on XQuery, in particular the fact that its not really a query language: it’s a programming language and folk are already using it in this context. But there’s much more to it. Semantic web folk will find much that will have them nodding in agreement.
Florescu suggests a number of concrete areas that require work. Amongst these are:

• Make XML a graph not a tree, by making links a first class part of the model
• Integrate the XML data model with RDF
• Extend programming capabilities of XQuery, e.g. to include assertions, error-handling, metadata extraction functions and continous queries. This latter area is interesting as it would allow an Xquery to run continously, acting on a stream of XML documents as they arrive
• Integrate XQuery with OWL and RDF. E.g. to allow searching an XML document by semantic classification of nodes, rather than their names.
• Make browsers XQuery aware, and developer a simple HTTP protocol for invoking XQuery on a remote repository. (I’ve been working with the SPARQL protocol recently and its occured to me several times that an equivalent for XQuery is an obvious area for further work)

All in all I find this to be a very thought-provoking presentation; there’s a lot of interesting ideas in there. For the Semantic Web crowd many of these will be old news: being able to query/manipulate data based on semantics is the core of RDF; linking as a first class model element is something we rely on constantly. But there’s also some new angles to consider. For example there’s a lot of work happening to tie programming languages in with XML, and XML vocabularies such as XQuery becoming more like scripting languages: what’s the equivalent in semantic web circles? Could an ontology aware version of XQuery provide a useful data manipulation environment?
I expect the XML-DEV thread to grow pretty quickly. Will be interested to see if this gets picked up and discussed by other communities also.

I see Micah’s latest XML-Deviant is up on XML.com this week, and its also to be the last in the series. It’s a shame to see it go as I’ve enjoyed reading the column over the last few years. I also thoroughly enjoyed contributing to the column during my own period of XML-Deviancy. But all things come to an end; I’m looking forward to seeing what replaces the column in future.
Tip of the hat to the other XML-Deviants: Edd, Kendall and Micah for all of their efforts along the way; especially Edd for originally conceiving of the column.

Belatedly (I only got back from Amsterdam last Monday), here are some notes from XTech Day 3.
On the Friday morning I initially attended two talks about RDF frameworks, firstly Dave Beckett’s Bootstrapping RDF applications with Redland and then David Wood’s introduction to
Kowari: A Platform for Semantic Web Storage and Analysis. I’ve not really used either of these toolkits yet, but at work we’re looking at trying out Kowari as one of the candidate triple stores for holding our massive dataset. John Barstow’s work on the port of Redland to windows makes it more likely that I’ll be trying out Dave’s toolkit for some personal hacking projects too.

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Liam Quin has been thinking about XML 2.0 and has posted an article to Advogato titled “Where Should XML Go?“.
Quin is obviously trying to reach a wider community than just the hardcode XML users, noting in his diary that: Where would you go (or post) to ask people why they’re not using XML? There are lots of good reasons not to use XML, and lots of good reasons to use it, so I’m particularly interested in people who would like to go with XML but who feel they can’t.
Advogato seems like a good starting place to me. Of course there’s an XML-DEV thread starting on the topic already, so the usual suspects will be weighing in very shortly.
I’m not sure what my most requested improvement to the core specification(s) would be. When asked about this before I’ve often responded that I’d be happy to see the work on packaging resume. Especially as there’s work continuing in the area that could be standardised, such as the Open Office format and Rick Jelliffe’s DZIP2.
I loved Jelliffe’s From Wiki to XML via SGML article demonstrating how to use SGML SHORTREFs to parse Wiki markup as SGML interesting, and thats made me wonder whether that might be an SGML feature worth unearthing. Not likely to be a popular suggestion though! And of course one can simply use an SGML parser when one needs the extra power.
But the syntax could certainly be friendlier, and I wonder whether that might address some users dislike of XML, the format; the can still use XML tools to process their config files, Wiki markup, CSV documents, etc.

I see by the fact that my complementary copy arrived today that XML Hacks has hit the stores. This makes me incredibly pleased as my two contributed hacks mean that this is the most I’ve ever had in print, and that’s like, proper writing, not this new-fangled web malarkey.
My two hacks are #64 (”Identify Yourself with FOAF”) and #93 (”Use Cocoon to Create a Well-Formed View of a Web Page, Then Scrape It For Data”). Both are RDF flavoured. The first is basically an edited version of my XML.com article, “Introduction to FOAF“, while the second is an original piece that provides a lightning introduction to Cocoon then shows how to create a simple web service that will scrape RDF metadata from a web page using a combination of HTML Tidy, XSLT and some rummaging around in the head element.
Kudos to Michael Fitzgerald for pulling together a book that contains such a wide range of useful hacks, and having the patience to do it whilst working with a number of very, very busy people!

The W3C have posted a Note discussing requirements for an XML Processing Model. This is good news, there’s been a lot of desire to see this work progressing for some time now. Wonder whether XML Pipeline will serve as a possible basis for a specification? It seems to be a good match to the requirements.
It’ll be interesting to see how this ties in with the DSDL work which is essentially defining a validation oriented processing framework. Frustratingly there’s been little updates to the DSDL web site to see how far they’ve progressed. This xmlhack report seems to have the most recent summary of activities. Please update your site DSDL people!