XML Developers' Day

By Bob DuCharme, XML Correspondent

On Friday, March 27th the Graphic Communications Association sponsored the " XML Developers Day" conference in Seattle, Washington. Coming the day after the end of the GCA's " XML '98" conference in the same hotel, it felt like an extension of the two-day conference, but with a very different emphasis: publicly available software currently under development.

The "under development" part was important because it gave the audience a sense of seeing potentially important XML software coming together in front of their eyes. Unlike similar conferences, Developers Day speakers were deliberately not asked to send papers about their projects in advance, because a published "Proceedings of the Conference" handed out at registration would have had three-month-old material-a long, long time considering the progress of XML software in early 1998.

The rough edges of some demoed software led to uncomfortable moments for the occasional speaker. Still, while watching a speaker crash and reboot his machine is annoying at most conferences, at Developers Day, it showed that you were seeing software with features that it didn't have the previous week as it evolved toward something potentially useful to all of us. It sure beat watching another suit spouting buzzwords in front of a PowerPoint bulleted list that told us why structured information is a Good Thing, a sight we saw too often on Wednesday and Thursday.

Some highlights:

The morning's first presenter was David Megginson, author of the most popular Perl modules for SGML and the book "Structuring XML Documents" (reviewed in the April issue of <TAG> ). He spoke about " SAX," the "Simple API for XML" developed cooperatively by members of the XML- DEV mailing list. Many XML parsers offer native or add-on SAX support so that writing to this Application Programming Interface lets the same application easily unplug one parser and plug in another. Among other advantages, this lets you develop an application using a big, full-featured, heavily-error-checking validating parser and then ship your finished application with a smaller, leaner, faster parser.

Megginson's talk set the tone for much of the conference, because although we heard about XML development using many programming languages during the day's other presentations, Java was clearly the most popular. Java is hot, but more importantly, Java and XML share one key goal that makes them ideal partners: easier deployment of distributed, thin-client applications with no dependence on any vendor's hardware or software. The proliferation of Java XML parsers is creating a snowball effect for Java XML development.

After Megginson's presentation, Naohiko Uramoto of IBM Research Laboratory in Tokyo demonstrated IBM's SAX-compliant Java XML parser. Its sample applications included a viewer and editor for CDF files (Microsoft's Channel Definition Format, a document type that they use for pushed MSNBC content) and a site outliner that creates CDF files. The whole thing, including demos, was a mere 240K.

Steph Tryphonas of Microstar demoed some new features of Near and Far, their DTD editing tool, that help to automate the conversion of SGMLDTDs to XMLDTDs. Tryphonas's discussion of the key issues of DTD conversion, and how much can and can't be automated, made his talk more informative than a straightforward product demo.

Larry Wall, inventor of the popular scripting language Perl, talked about changes to Perl and new libraries being written to better accommodate XML. This is huge news, because while Perl has been a popular tool for SGML development, SGML has been a minor Perl application category compared to the scripting language's huge deployment for Web CGI scripting, easy TCP/ IP socket work, database interfaces, general text processing, and combinations of all of these. The news that Wall would change Perl itself to better accommodate an SGML offshoot came as quite a surprise to those of us who started off years ago with the SGMLS parser's sgmls.pl tool and then moved on to David Megginson's SGML Perl modules. For now, the biggest single planned change is better Unicode support; Wall's plans for the future include "tag-savvy regular expressions." This is a huge leap for Perl in the battle for popularity among scripting languages used for XML processing.

Scott Parnell of Xerox demonstrated Raven, their Java-based homegrown XML editor. It was designed for use with small, simple documents such as memos and status reports, because according to Parnell, doing these with FrameMaker "is like driving finishing nails with a sledgehammer." Raven, which was built using Java Beans and Microsoft's Java XML parser, was developed for internal use at Xerox and not for release as a publicly available product, but audience questions for Parnell after his talk demonstrated a key purpose of Developers Day: allowing people creating XML applications to learn from others writing similar ones.

Henry Thompson of the Center for Cognitive Science in Edinburgh, Scotland (and author of several DSSSL tools including the xslj XSL-to- DSSSL style sheet translator) demonstrated his " XED" XML editor, which he wrote with Tcl, Python, and some C libraries. I've played with it myself, and he's got a great start. Thompson described why he wrote XED: not as a proof of concept or sample demo application to get familiar with the technology, but as a common tool to integrate document creation and communication between the software developers at the Center for Cognitive Science (who otherwise use UNIX text editors such as vi and Emacs) and the support staff, who all use Microsoft Word.

Norm Walsh of ArborText (whose extracurricular activities include the DocBook DSSSL stylesheets) demonstrated XML Styler, an interactive tool that creates and edits XSL stylesheets. ArborText deserves kudos for making this program, which has no dependencies on any of its products that I know of, freely available on its web site. Even the earliest adopters of XSL technology may never need to deal directly with XSL syntax now that a slick graphical user interface stylesheet editor is available well in advance of the XSL spec's ascent to W3C Recommendation status.

The biggest news of the day, if not the week, was the demo by Netscape's Ramanathan Guha of the XML support in its upcoming Navigator 5.0 browser. After displaying a typical-looking Web page, he selected "Page Source" from the "View" menu to reveal that he had been browsing an XML document with a CSS style sheet, not an HTML web page. Later reports in hi-tech press publications such as InfoWorld and Wired News revealed that this was the first public display of this capability, and it was certainly newsworthy. Because this came only a few days before the public release of the Netscape "Mozilla" source code version of Navigator, Netscape wanted the world to know that along with the source code for features they had seen before, there were great new features to look forward to. After lagging so far behind Microsoft in XML support, Netscape's leapfrogging of Internet Explorer was quite a public relations coup. I can't wait to see Microsoft's response.

Coverage from the mainstream press was impressive considering the conference's size. "The XML Developers' Days are pretty small potatoes compared with the usual run of industry events I've been involved with lately-the big GCASGML events, Seybold, Internet World, and the International WWW conferences," said Jon Bosak, the conference Chair. "But I honestly have to say that I think they've provided more benefit-per-minute for their attendees than any of the big ones."

Bosak also described the format and future of the conference: "I orginally came up with the idea of an 'anti-conference' (no formal papers, no vendor presentations, and just one track devoted strictly to technical issues) entirely to suit myself, but it looks like the format pleases enough other people to keep these things going. I asked the audience at the Seattle Developers' Day whether we should make the event two days instead of one, and a clear majority said yes. Steve Newcomb and I have been discussing the August GCA Metastructures conference in Montreal, and we're thinking of doing just that."

Given the progress we saw in Seattle in March, one day won't be enough in August. <end/>