RE: Server Side Magic.

In our practice, we've been abstracting all data into W3C DOM Documents for
styling to various devices using "themes" (collections) of client-specific
XSL stylesheets for years, and it works well.  Apache Cocoon, which evolved
out of the Apache Xang project (which we wrote and contributed to Apache),
includes many of the tools necessary to do this.  As for this approach's
suitability "for public web pages", I'm unsure what is meant by the phrase.
If it refers to scalability, our server product, which also evolved out of
Apache Xang, and which includes significant improvements for data and page
caching and load balancing, is routinely deployed to customers with many
thousands of users.  As with any software, implementation practices can play
a huge part in performance; I have seen XSLT inclusion and template-matching
errors that can slow a page load from 4 seconds to 20 sec. or even 40 sec.
Another approach which we've worked with is W3C DOM + JSP instead of XSLT,
which has the added benefits of JIT compilation and a more robust language
and tools.

If your client considers alternate Web clients to be just PDAs or the new
Phones+PDA, which have rudimentary HTML browsers, then HTML for a small
screen can work great (provided that you use HTML 3.2 and no client-side
JavaScript, imagemaps, CSS, frames, etc.).  But when your client is more
broad-minded and demands (or will demand) support for a variety of
Internet-enabled devices, such as WAP, 2-way pagers (RIM Blackberry),
VoiceXML, Web Services clients, smart Web printers, television set-top
boxes, and so forth, then a disciplined separation of presentation and
business logic is vital to keeping the task manageable, and XML is
frequently the ideal technology for the job.

- JayZ

-----Original Message-----
From: Tom Worthington [mailto:tom.worthington@tomw.net.au]
Sent: Monday, June 18, 2001 8:12 PM
To: Juha Vierinen; www-mobile@w3.org; www-tv@w3.org
Subject: Re: Server Side Magic. 
Importance: Low


At 07:21  18/06/01 +0300, Juha Vierinen wrote:
>We are planning to test CC/PP ... The server has to do some magic, to come 
>up with a page which fits the client... Is there any standardized language 
>for describing a such a site?

You might want to look at Cocoon, a "100% pure Java publishing framework 
that relies on new W3C technologies (such as DOM, XML, and XSL) to provide 
web content": http://xml.apache.org/cocoon/

However, I am a skeptical of the value of this technology for public web 
pages. After discussions of accessibility and mobile Internet at INET2001 
<http://www.tomw.net.au/2001/inet/index.html#Serving>, I am recommending 
that web designers make their applications "wireless ready" by implementing 
accessibility guidelines and checking their web pages are usable on a 
quarter-VGA screen. Most web pages will then work okay on wireless PDA 
devices and web appliances, as well as normal computer screens. This avoids 
the need for server side software and bypasses WAP.


Tom Worthington FACS tom.worthington@tomw.net.au Ph: 0419 496150
Director, Tomw Communications Pty Ltd ABN: 17 088 714 309
http://www.tomw.net.au PO Box 13, Belconnen ACT 2617
Visiting Fellow, Computer Science, Australian National University
Publications Director & Past President, Australian Computer Society
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