|
XML and Web Services In The News - 3 January 2007
Provided by OASIS |
Edited by Robin Cover
This issue of XML Daily Newslink is sponsored by IBM Corporation
HEADLINES:
Software Development: Simplicity Tops the Agenda
Andrew Binstock, InfoWorld
Software development continued to move toward simplicity in 2006. Most
evident was the widespread adoption of SOA, which has become the
technology of choice for integrating systems of all kinds — in-house
between departments, across stovepipe applications, and in B2B and B2C
commerce. Web services became easier to develop and use as a result of
the emerging popularity of REST (Representational State Transfer).
REST does away with SOAP wrappers and other overhead, bringing Web
services down to the simplest possible implementation: an XML file sent
over the wire via HTTP. Four basic commands (the REST equivalent of CRUD),
combined with resource files, make all actions simple to implement.
REST is likely to replace much of socket-based communication and a good
portion of SOAP-based services as well, especially in straightforward
applications where solutions need to be cobbled together quickly. Java 6,
released in December, added numerous features to simplify development.
It also added better support for scripting languages. One language
primarily associated with simplicity, Ruby, will tap these benefits with
JRuby, a JVM implementation that should ship in 2007. Likewise, an
elegant scripting language called Groovy, due to ship in early 2007,
will put the fun back into Java programming. Frameworks such as Spring
and Ruby on Rails continued gaining in popularity and commercial support,
as developers and their managers came to accept the view that many
business apps don't need the heavy enterprise aspects. By giving up some
features, and especially scalability, these frameworks have enabled
many sites to cut a swath through their backlog. The rise of lightweight
frameworks, the continued popularity of scripting languages, and the
success of SOA show that IT sites and developers are increasingly
relying on simpler technologies.
See also: Atom references
Q&A from James Bryce Clark: Dynamic SOA Coming in 2007
Rich Seeley, SearchWebServices.com
In this second part of a Q&A interview with James Bryce Clark (Director
of Standards Development for OASIS), Clark talks about the future of
semantic standards to make more intelligent use of the information
organizations rely on for their business applications. Clark: [on
knowledge representation] "Among the things that are happening now to
bring KR, knowledge representation, into our field are all the taxonomy
and ontology projects. There are also three business rules projects.
Semantic markup people are doing great work. There are several
candidates and it's hard to say who will win out because they have
different models. But when our people on OASIS committees want to add
semantic information to their models there are ways to do it. And it's
very important to add that functionality. Also, a lot of the action in
adding semantic content, in making business documents smarter, isn't
necessarily happening through large complex academic exercises. There
are a lot of fairly light methods for adding information that also seem
to be gathering a lot of steam. Because not everybody who wants to make
their business information smarter wants to go down the road of
re-writing everything they have, and hiring four PhDs, and doing
ontological research. Sometimes they just want to get a little more
metadata or a little more organization. There are a number of really
cool methods for doing that that are becoming mature now. One of them
that is happily at OASIS is Darwin Information Typing Architecture (DITA).
Also there's BPEL, which is widely used. A lot of complex transaction
engines and business rules engines are proprietary and have their own
models. Nevertheless, they use BPEL for their exchange format. Vendors
of systems that orchestrate and run transactions with their own engine
that's not necessarily standardized, most of them support BPEL now.
That's something I didn't expect to see. It's become an important
exchange format. A customer who commits to the Foo Company's method of
running their transactions, knows that if they ever want to switch out
of Foo Company, the use of BPEL will help them move their data out in
a standard format.
See also: Part 1
Justice Reference Architecture (JRA) Specification Version 1.3
U.S. DOJ Global Infrastructure/Standards WG, Draft Specification
Members of the United States Department of Justice GISWG Executive
Architecture Committee (EAC) have announced the release of the Global
Justice Reference Architecture (JRA) Specification Working Draft
Version 1.3. The document is now available on U.S. OJP's Technology
and Global Web Site, and is open for public comment through January 16,
2007. The document states a set of requirements for justice
interoperability and then describes the Justice Reference Architecture
(concepts, relationships, and high-level components) Specification
that satisfies those requirements. The document then illustrates the
architecture through a set of actual scenarios. Finally, the document
provides an initial elaboration of some of the concepts and components
in the architecture. This report is intended as a resource for a
technical audience, including Global Justice XML Data Model (Global
JXDM) implementers, architects, developers, system integrators, and
other justice and public safety technical practitioners. It provides
the background and concepts & a strong foundation & required for
the implementation of SOA. Justice Reference Architecture is a new
term coined for the justice community, and it is derived from the OASIS
Reference Model for Service-Oriented Architecture 1.0 (SOA-RM ). The
reader should refer to the SOA-RM for more detailed information about
many of the concepts in this document. JRA is intended to facilitate
your SOA implementation by establishing a common language that can be
used to exchange data with partner organizations. Solving
interoperability challenges continues to be a significant problem and
a high priority for the justice and public safety community. There are
approximately 100,000 justice agencies that have the critical need to
share information across their various information systems, and this
variety creates multiple layers of interoperability problems because
hardware, software, networks, and business rules for data exchange
are different. The need for information sharing has led to this
interoperability strategy and the Justice Reference Architecture (JRA).
See also: the reference page
W3C Publishes Approved TAG Finding on the Use of Metadata in URIs
W3C Technical Architecture Group, TAG Finding
W3C announced the publication of an Approved TAG Finding, produced by
members of the W3C Technical Architecture Group (TAG). Edited by Noah
Mendelsohn and Stuart Williams, this finding "addresses several
questions regarding Uniform Resource Identifiers (URIs). Specifically,
what information about a resource can or should be embedded in its URI?
What metadata can be reliably determined from a URI, and in what
circumstances is it appropriate to rely on the correctness of such
information? In what circumstances is it appropriate to use information
from a URI as a hint as to the nature of a resource or its
representations? Simple examples are used to explain the tradeoffs
involved in employing such metadata in URIs." From the Conclusions:
(1) It is legitimate for assignment authorities to encode static
identifying properties of a resource, e.g. author, version, or creation
date, within the URIs they assign; this may contribute to the unique
assignment of URIs. (2) Assignment authorities may publish specifications
detailing the structure and semantics of the URIs they assign. Other
users of those URIs may use such specifications to infer information
about resources identified by URI assigned by that authority. (3) The
ability to explore and experiment is important to Web users. Users
therefore benefit from the ability to infer either the nature of the
named resource, or the likely URI of other resources, from inspection of
a URI. Such inferences are reliable only when supported by normative
specifications or by documentation from the assignment authorities. In
other cases, users should be aware that their inferences may be incorrect
and the effect could be malicious. (4) People and software using URIs
assigned outside of their own authority should make as few inferences
as possible about a resource based on its URI. The more dependencies a
piece of software has on particular constraints and inferences, the
more fragile it becomes to change and the lower its generic utility.
See also: other TAG Findings
Working XML: Understand the Various Approaches to XML Parsing
Benoit Marchal, IBM developerWorks
Where does every XML processing start? Through parsing. Parsing is
probably the most fundamental service available to developers. The
parser reads the XML document, decodes the syntax and passes meaningful
objects to the application. The parser might also provide additional
services such as validation — making sure the document conforms to an
XML Schema or a DTD — or namespace resolution. This article introduces
the various approaches to parsing and highlights their pros and cons
to help you decide on the tools for your next XML project. It includes
links to more articles so when you decide on a tool, you can study the
technicalities of a given API. Granted, XML is not a very complex
syntax so you can be forgiven for thinking that you can hack your way
with regular expressions or other ad-hoc means. In practice it seldom
works: XML syntax requires support for multiple encodings and many
subtleties, such as CDATA sections or entities. Home-made
implementations almost never cater to all these aspects and they create
incompatibilities. Conversely, the parsers that ship with development
environments were tested with an eye towards compatibility. Because the
main reason to adopt a standard syntax like XML is to be compatible with
other applications and toolkits, this is one case where it really pays
to use a well-tested library. Most parsers offer at least two different
APIs, typically an object model API and an event API (also called stream
API). The Java platform, for example, ships with both DOM (Document
Object Model) and SAX (Simple API for XML). Both sets of APIs offer
the same services: decoding of the document, optional validation,
namespace resolution, and more. The difference is not in the services
but in the data model used by the API. The API you use to read an XML
document has a significant impact on the overall performance of your
application, so take time to familiarize yourself with the options and
choose the best option for your platform, programming language and,
more importantly, your project. Generally speaking, event APIs consume
fewer resources and, therefore, can be more efficient, but if you store
the whole document in memory anyway, then an object API is a better
choice because it saves a lot of coding.
New Year, New Look For PC-BSD
Sean Michael Kerner, InternetNews.com
Linux isn't the only open source operating system vying for the desktop;
BSD in the form of the PC-BSD effort is too. It builds on the FreeBSD
6.1 base with an operating system that is more tailored for desktop
users. Among the improvements in PC-BSD 1.3 is a new install wizard that
allows for multiple users to be added at installation time. The new
install wizard also provides advanced options for firewall, network and
storage partitions. The new PC-BSD also sports a new look and a new
base system using the KDE 3.5.5 desktop. Developers have also updated
the Hardware Abstraction Layer (HAL) in version 1.3 for improved
hardware access. But HAL isn't necessarily entirely reliable for PC-BSD
1.3 just yet. The release notes for PC-BSD 1.3 warn that this is the
first release of PC-BSD that incorporates HAL support for the media
backend. An open source project in and of itself can't really be acquired,
so what it actually acquired was intellectual property and copyrights
related to the development of PC-BSD and associated domains, as well as
the brains behind the operation, according to Matt Olander CTO
iXsystems. Kris Moore, founder of the PC-BSD project, is one of those
brains who is now working full time on the project.
Opinion: The Free Multimedia Opportunity
Neil McAllister, InfoWorld
With Windows Vista on the horizon, the fate of desktop Linux could rest
in open media formats. As 64-bit processing becomes mainstream, the
next major computing platform shift is due to arrive by 2008. If the
open source community doesn't step up to the plate and address major
impediments to widespread desktop adoption, Linux could be left behind.
So say Eric S. Raymond and Rob Landley in their essay, "World
Domination 201," published in November. The issue, they point out, is
that Linux simply doesn't work out of the box for many of the things
that an average computer user expects to do. Chief among these
deficiencies is lack of support for many popular multimedia formats.
They have a point. Multimedia has always been a difficult challenge for
Linux, owing to the quagmire of proprietary codecs and file formats
and the accompanying patents that protect them. Linux newbies would
doubtless be surprised to learn that few distributions even bundle
support for basic MP3 playback these days, out of fear of litigation.
the war for free and open multimedia must be fought on two fronts.
While it's important that Linux support all the capabilities that
commercial operating systems offer, we must also continue to encourage
aggressively the adoption of open formats and codecs wherever possible.
Fortunately, we have been presented with an opportunity that is of the
enemy's own making. Even as the computer industry is readying for a
major platform shift in a few years, the content industry is likewise
planning a major shift in how multimedia is delivered. New formats,
including HD-DVD and Blu-ray, incorporate copy protection technologies
that restrict how the content can be used but do nothing to improve
the viewer's experience. Coupled with the draconian copy protection
systems introduced with Windows Vista, these technologies make PCs
less useful, less reliable, and more costly, according to an analysis
by security expert Peter Gutmann.
XML.org is an OASIS Information Channel
sponsored by BEA Systems, Inc., IBM Corporation, Innodata Isogen, SAP AG and Sun
Microsystems, Inc.
Use http://www.oasis-open.org/mlmanage
to unsubscribe or change an email address. See http://xml.org/xml/news_market.shtml
for the list archives. |
