This issue of XML Daily Newslink is sponsored by:
SAP AG http://www.sap.com
DocBook V5.0: The Transition Guide
J. Kosek, N. Walsh, D. Hamilton, M. Smith (eds), Technical Report
Jirka Kosek announced the availability of an updated "howto" DocBook Version 5.0 Transition Guide. The document is targeted at DocBook users who are considering switching from DocBook V4.x to DocBook V5.0. It describes differences between DocBook V4.x and V5.0 and provides some suggestions about how to edit and process DocBook V5.0 documents. There is also a section devoted to conversion of legacy documents from DocBook 4.x to DocBook V5.0. The differences between DocBook V4.x and V5.0 are quite radical in some aspects, but the basic idea behind DocBook is still the same and almost all element names are unchanged. Because of this it is very easy to become familiar with DocBook V5.0 if you know any previous version of DocBook. For more than a decade, the DocBook schema was defined using a DTD. However DTDs have serious limitations and DocBook V5.0 is thus defined using a very powerful schema language called RELAX NG. Thanks to RELAX NG, it is now much easier to create customized versions of DocBook, and some content models are now cleaner and more precise. The Technical Committee provides the DocBook 5.0 schema in other schema languages, including W3C XML Schema and an XML DTD, but the RELAX NG Schema is the normative schema. All DocBook V5.0 elements are in the namespace http://docbook.org/ns/docbook. XML namespaces are used to distinguish between different element sets. In the last few years, almost all new XML grammars have used their own namespace. It is easy to create compound documents that contain elements from different XML vocabularies. The namespace name http://docbook.org/ns/docbook serves only as an identifier. This resource is not fetched during processing of DocBook documents and you are not required to have an Internet connection during processing. If you access the namespace URI with a browser, you will find a short explanatory document about the namespace. In the future this document will probably conform to (some version of) RDDL and provide pointers to related resources.
See also: DocBook V5.x
First Working Draft: Content Transformation Landscape 1.0
Jo Rabin and Andrew Swainston (eds), W3C Technical Report
See also: the Content Transformation Task Force
RDFa Primer: Embedding Structured Data in Web Pages
Ben Adida and Mark Birbeck (eds), W3C Technical Report
The updated version of "RDFa Primer" provides an introduction to RDFa, a method for structuring data by embedding in XHTML. This version of the RDFa Primer is a substantial update to the previous version, representing several design changes since the previous version was published. Current Web pages, written in XHTML, contain inherent structured data: calendar events, contact information, photo captions, song titles, copyright licensing information, etc. When authors and publishers can express this data precisely, and when tools can read it robustly, a new world of user functionality becomes available, letting users transfer structured data between applications and Web sites. An event on a Web page can be directly imported into a desktop calendar. A license on a document can be detected to inform the user of his rights automatically. A photo's creator, camera setting information, resolution, and topic can be published as easily as the original photo itself. RDFa lets XHTML authors express this structured data using existing XHTML attributes and a handful of new ones. Where data, such as a photo caption, is already present on the page for human readers, the author need not repeat it for automated processes to access it. A Web publisher can easily reuse data fields, e.g. an event's date, defined by other publishers, or create new ones altogether. RDFa gets its expressive power from RDF, though the reader need not understand RDF before reading this document. RDFa uses Compact URIs, which express a URI using a prefix.
Data Sources as Web Services
Kyle Gabhart, XML.com
WSO2 ('WS OH 2') is growing in popularity and the team continues to produce quality products. The WSO2 (a.k.a. Web Services Oxygen Tank) team that has pulled together a platform around Apache SOA projects, producing an application server, ESB, Web 2.0 mashup engine, and more. Most recently, they have released Version 2.1 of the Web Services Application Server (WSAS). The release includes a lot of compelling features, but this article focuses upon WSO2 Data Services—a new feature available in WSO2's WSAS 2.0 platform. The author introduces Data Services, examining their architecture and utilization, and exploring pros and cons of this convenient feature. Data services are standard web services that have been configured within WSAS to map to data source calls to one or more backend data sources. Configuration is captured in XML and can either be performed by hand and uploaded as a complete deployment module, or deployed via the web-based Data Service configuration wizard. Once deployed, these services can either be consumed by other WSAS services or be made available to external clients. Data Services are essentially the SOA-equivalent of the Data Access Object pattern. Granted, Data Services are at a much higher level of abstraction, but they serve a similar role in a layered architecture. They enable higher level services or even client applications to access underlying datasets without regard for the implementation details involved... The heart of any enterprise application is data. Applications provide the ability to view, sort, filter, edit, create, and delete data. In a SOA, access to data is also paramount. Typically this involves wrapping an existing business object (EJB or POJO) with a web service. Another option is to bypass this additional layer and directly expose data capabilities via WSO2 Data Services. Data services are convenient, configurable, and great for service oriented data for a demo or even as a part of a SOA.
Mashups: The Evolution of the SOA
Stephen Watt, IBM developerWorks
Growing Pains: Can Web 2.0 Evolve Into An Enterprise Technology?
Andy Dornan, InformationWeek
Selected from the Cover Pages, by Robin Cover
The DRAMA (Digital Repository Authorization Middleware Architecture) development team at MELCOE, Macquarie University, Sydney, Australia has announced the release of Muradora Version 1.0, described as a turnkey GUI for the Fedora Repository supporting federated identity and flexible access control. Fedora is a general purpose repository system developed jointly by Cornell University Information Science and the University of Virginia Library. The Fedora Project is devoted to the goal of providing open-source repository software and related services to serve as the foundation for many types of information management systems. The Fedora software is available under the terms of the Educational Community License 1.0 (ECL). Fedora was selected for Muradora because it is widely used, is recognized as scalable (supporting more than one million objects), and has an exxellent digital object model. The project goals are to support collaboration between researchers for access and search across institutional protected repositories, with an easy to use and maintain access control system requiring little or no intervention from system administrators. Muradora incorporates a suite of software modules to deal with the needs for federated identity and flexible authorisation for repositories. Key Muradora modules include Shibboleth (SAML) authentication for federated identity/single-sign-on, a Fedora authorization framework based on XACML, an extended XACML engine using DB XML for policy enforcement, and web service interfaces for XACML requests and responses.
XML Daily Newslink and Cover Pages are sponsored by:
|BEA Systems, Inc.||http://www.bea.com|
|Sun Microsystems, Inc.||http://sun.com|
XML Daily Newslink: http://xml.coverpages.org/newsletter.html
Newsletter Archive: http://xml.coverpages.org/newsletterArchive.html
Newsletter subscribe: firstname.lastname@example.org
Newsletter unsubscribe: email@example.com
Newsletter help: firstname.lastname@example.org
Cover Pages: http://xml.coverpages.org/