Cover Pages: XML Daily Newslink: Wednesday, 11 February 2009

A Cover Pages Publication http://xml.coverpages.org/
Provided by OASIS and Sponsor Members
Edited by Robin Cover

This issue of XML Daily Newslink is sponsored by:
Oracle Corporation http://www.oracle.com

Headlines

Mapping YANG to Document Schema Definition Languages (DSDL) and Validating NETCONF Content
Content Management Interoperability Services: Unified Search Proposal
Preventing Standards Death March, Augmenting RELAX NG to Support Variants
Sun's GlassFish Portfolio Could Change Middleware Game
Altova MissionKit 2009 Supports XBRL, HL7
Implementing AtomPub in Less Than a Thousand Lines of XQuery
Resource Reservation Protovol (RSVP) Extensions for Emergency Services
Developing a CICS-Based Web Service
Letter to Obama: Consider Open Source

Mapping YANG to Document Schema Definition Languages (DSDL) and Validating NETCONF Content
Ladislav Lhotka, Rohan Mahy, Sharon Chisholm (eds), IETF Internet Draft

Members of the IETF NETCONF Data Modeling Language (NETMOD) Working Group have published an initial -00 level Internet Draft for "Mapping YANG to Document Schema Definition Languages and Validating NETCONF Content." The document provides the specification of a mapping that translates YANG data models to XML schemas utilizing a subset of the Document Schema Definition Languages (DSDL) schema languages... "Since NETCONF uses XML for encoding its protocol data units (PDU), it is natural to express the constraints on NETCONF content using standard XML schema languages. For this purpose, the NETMOD WG selected the Document Schema Definition Languages (DSDL) that is being standardized as ISO/IEC 19757. The DSDL framework comprises a set of XML schema languages that address grammar rules, semantic constraints and other data modeling aspects but also, and more importantly, do it in a coordinated and consistent way... The mapping procedure is divided into two steps: In the first step, the structure of the data tree, RPC signatures and notifications is expressed as a single RELAX NG grammar with simple annotations representing additional data model information (metadata, documentation, semantic constraints, default values etc.). The second step then generates a coordinated set of DSDL schemas that can validate specific XML documents such as client requests, server responses or notifications, perhaps also taking into account additional context such as active capabilities... The main objective of this work is to complement YANG as a data modeling language by validation capabilities of DSDL schema languages, primarily RELAX NG and Schematron. The ultimate goal is to be able to capture all substantial information contained in YANG modules and express it in DSDL schemas. While the mapping from YANG to DSDL described in this document is in principle invertible, the inverse mapping from DSDL to YANG is not in its scope. XML-encoded data appear in several different forms in various phases of the NETCONF workflow - configuration datastore contents, RPC requests and replies, and notifications. Moreover, RPC methods are characterized by an inherent diversity resulting from selective availability of capabilities and features. YANG modules can also define new RPC methods. The mapping should be able to accommodate this variability and generate schemas that are specifically tailored to a particular situation and thus considerably more efficient than generic all-encompassing schemas. In order to cope with this variability, we assume that the schemas can be generated on demand from the available collection of YANG modules and their lifetime will be relatively short. In other words, we don't envision that any collection of DSDL schemas will be created and maintained over extended periods of time in parallel to YANG modules. The generated schemas are primarily intended as input to the existing XML schema validators and other off-the-shelf tools. However, the schemas may also be perused by developers and users as a formal representation of constraints on a particular XML-encoded data object.

Content Management Interoperability Services: Unified Search Proposal
Gregory Melahn (ed), Working Draft Level CMIS Contribution

Members of the OASIS Content Management Interoperability Services (CMIS) Technical Committee are working on designs to support unified search in the CMIS specification. From the initial draft: "This document is a proposal for a modification to the draft CMIS specification. The new service described in this proposal will allow search crawlers to navigate a CMIS repository." From the 'Introduction' section: "CMIS has introduced a capability that allows repositories to expose what information inside the repository has changed in an efficient manner for applications of interest, like search crawlers, to leverage to facilitate incremental indexing of a repository. In theory, a search crawler could index the content of a CMIS repository by using the navigation mechanisms already defined as part of the proposed specification. For example, a crawler engine could start at the root collection and, using the REST bindings, progressively navigate through the folders , get the document content and metadata, and index that content. It could use the CMIS date/time stamps to more efficiently do this by querying for documents modified since the last crawl. But there are problems with this approach. First, there is no mechanism for knowing what has been deleted from the repository, so the indexed content would contain 'dead' references. Second, there is no standard way to get the access control information needed to filter the search results so the search consumer only sees the content (s)he is supposed to see. Third, each indexer would solve the crawling of the repository in a different way (for example, one could use query and one could use navigation) causing different performance and scalability characteristics that would be hard to control in such system. Finally, the cost of indexing an entire repository can be prohibitive for large content, or content that changes often, requiring support for incremental crawling and paging results..." See also "CMIS Unified Search Design Discussion" (11-February-2009): [We] "need to ensure that this service, which is really an observation pattern, can be extensible in the future to satisfy other use cases than search. For example, if this were to be applied to audit as well as search, then it would need to also answer who changed the item, why it was changed (e.g., comments), what was changed (specific properties that were changed). Another use case to which this could be applied is replication..."

Preventing Standards Death March, Augmenting RELAX NG to Support Variants
Rick Jelliffe, O'Reilly Radar

ISO standards can, at committee request, be marked stable, which means they are not expected to change. That this is not the default may be surprising to some people, especially if you have some kind tablets of stone view of standards. In the particular cases of OOXML and ODF, I think there is a strong need to find maintenance models that are both workable, don't disenfranchise their champions, give all stakeholders an equal voice, and prevent death marches. I suspect ODF and OOXML are both very prone to the death march (i.e., where a project just drags on, swamped by feature creep and committee paralysis. I suggest there are two important practical issues, apart from the organizational behaviour of committees. (1) Schedule releases, and (2) Variants. As to scheduled releases: The first is that I think the ODF and OOXML standards should move to a strictly timed release cycle. So ODF 2009, ODF 2010, ODF 2011, OOXML 2009, OOXML 2010, and so on. ISO standards are already year stamped. At a particular deadline point in the year, all the maintenance items agreed to in the committee would get collected and rolled into a new version. As to variants: schema languages can support variants and evolution with first class constructs. Schematron's phase mechanism lead the way here, but I see no reason why grammars might not usefully have some other kind of mechanism. For example, here is a possibility for RELAX NG: this could be implemented by a macro pre-processor of the schema, or combined with the language... We allow patterns (on the condition that they only are 'true()' or 'false())' to be specified in the command-line, overriding pattern values in the schema. This gives us, in effect, a boolean conditional language. Dave Peterson was advocating that SGML needed something like this in the mid 1990s: I suppose that the variant issues that SGML DTD faced after 8 years or so of the release of SGML is similar to the problems we face now with schemas, 8 years or so after the release of XML and XSD. This gives the ability to capture various different schemas in a single language, which makes the history of the changes more explicit.

Sun's GlassFish Portfolio Could Change Middleware Game
Vance McCarthy, Integration Developer News

This week, Sun Microsystems enters the open source middleware space with GlassFish Portfolio, a pre-integrated and easily configurable platform that offers an ESB, management and monitoring capability, a web portal for community development, and LAMP stack. Sun's GlassFish Portfolio release looks to leverage its successful open source GlassFish Application Server, which now boats some 900,000 downloads. The GlassFish Portfolio includes the GlassFish Application Server, along with the following new components: (1) Sun GlassFish ESB: A lightweight, open source ESB platform for department-scale and enterprise SOA deployments that connects existing and new applications to deliver content and services to the Web. The technology is based on Sun's Open ESB and the Java Composite Application Platform Suite (Java CAPS). (2) Sun Enterprise Manager: For enterprise scale management and monitoring of the GlassFish Portfolio including SNMP (Simple Network Management Protocol) support. Support to use GlassFish Enterprise Server also meets high-availability and high-scale mission- critical requirements. (3) Sun GlassFish Web Stack: A complete and fully integrated LAMP stack designed for developers wanting a light-weight Web solution. The GlassFish Web Stack includes Tomcat, Memcached, Squid and Lighttpd with support for PHP, Ruby and the Java platform. (4) Sun GlassFish Web Space Server: Based on Liferay Portal, the leading open source portal technology, helps companies simplify Web site development and build collaborative work spaces, including portals and social networking sites. Mark Herring (Sun VP of Software Infrastructure Marketing): "In conventional LAMP stack implementations, for instance, sometimes a patch can come out for one of the components and it can destroy a lot of hard work. The GlassFish Portfolio is battle-tested for enterprise deployment, with special attention to the precise pre-integration work needed to ensure performance and reliability." From the announcement: "Companies developing Web applications with the Sun GlassFish Portfolio can expect to deploy quickly, see a seven fold improvement in application price/ performance at only 10 percent of the cost - over proprietary offerings. Built on leading open source projects including: Apache Tomcat, Ruby, PHP, Liferay Portal and GlassFish, the Sun GlassFish Portfolio packages these components into a complete, pre-integrated and fully-tested open source platform, resulting in increased productivity and faster time to market. Because the Sun GlassFish Portfolio is based on the industry's highest performing application server, GlassFish Enterprise Server, it is suited for extremely high-scale mission-critical environments, as well as departmental applications... GlassFish Portfolio and MySQL Enterprise are both available from Sun with consistent pricing and subscription support models so customers have a single vendor to stand behind their open source deployments."

See also: the Sun announcement

Altova MissionKit 2009 Supports XBRL, HL7
Martin Heller, InfoWorld Blog

XBRL changes everything in terms of business intelligence, and Altova is making XBRL generation and reporting much simpler... It's not like XBRL is a simple XML schema: that would unfortunately not be able to capture the complexity of standard financial reports, much less the individualized extensions that most companies make to the standards to reflect their own charts of accounts. If you look in the overview section of the [example] screen shot you see that there are about ten different files feeding into one XBRL document. Most of them are US-GAAP and XBRL standards that companies never touch; only a few are company-specific extensions. However, the overall complexity is daunting, given that an "item" can be a whole reporting hypercube, as you can see near the lower left. Given all that complexity, how could a company ever comply with the XBRL reporting mandate? According to Alexander Falk (Altova, CEO) some of his competitors provide tools for adding tags to PDF files to generate XBRL from existing reports. Altova takes the opposite approach: it provides tools for generating XBRL from the accounting database, and also for generating formatted reports in PDF and several other formats from the XBRL... Is this important beyond compliance with SEC requirements? W. David Stephenson, who is writing a book about data transparency, says that access to real-time data through a format such as XBRL "changes everything" in terms of business intelligence. Stephenson points to the Netherlands, which has been a pioneer in the use of XBRL, where companies have the option of filing one XBRL report instead of separate written reports to 30-40 different agencies. The Dutch government is projecting enormous savings from this report consolidation; there's also a tremendous additional advantage that the required data elements have been consolidated from 200,000 to 8,000... [From the Altova announcement:] "Comprehensive support for working with Extensible Business Reporting Language (XBRL) data is now available in the Altova MissionKit Version 2009 (v2009), its integrated suite of XML, database, and UML tools. A host of powerful, new features allow users to view, edit, validate, map, and publish XBRL data. With intelligent wizards, graphical drag-and-drop design models, and various code generation capabilities, the MissionKit Version 2009 gives developers, technical professionals, and power users one easy-to-use suite of tools for transforming XBRL data into content that can be shared with business partners, stakeholders, and regulatory commissions... Altova's XML editor for modeling, editing, transforming, and debugging XML technologies now delivers new support for XBRL validation and taxonomy editing. A new engine in XMLSpy supports the validation of documents created based on XBRL 2.1 and XBRL Dimensions 1.0. This allows users to view and analyze XBRL taxonomies as well as validate XBRL instance documents against taxonomies. A powerful, graphical XBRL taxonomy editor has also been added in XMLSpy 2009. The XBRL taxonomy editor uses the same editing paradigm as the popular XMLSpy graphical XML schema editor, providing a visual representation of XBRL taxonomies. Altova's graphical data mapping, conversion, and integration tool now supports drag-and-drop mapping of XBRL taxonomies as a source or target in any data mapping project..."

Implementing AtomPub in Less Than a Thousand Lines of XQuery
Norman Walsh, Blog

A few weeks ago, I decided to build a conformant AtomPub server implementation on MarkLogic Server. Mosty for fun, but partly with an eye towards using it for some future reimplementation of this weblog. In any event, it's up and running on my test server... The executive summary: dead easy to implement in MarkLogic Server. I built a flexible, conformant AtomPub server in less than a thousand lines of XQuery. The only tricky part, really, was getting the security right. But when isn't it tricky to get security right? It's very convenient in a lot of applications to rely on 'application level' security. You give all your XQuery code full privileges to the whole system and rely on your coding skills to manage access. This is very flexible and convenient, but it doesn't work for AtomPub. AtomPub clients expect to use HTTP authentication to gain access to the server, so that's what you have to provide. Unlike a human user on a web browser, where you might implement a floating, 'web 2.0' style login box, or its accessible equivalent, for a machine operating over a wire protocol, you have to reply with and respond to the proper HTTP authentication challenges. Generally speaking, what this means is that you have to provide two URIs for each resource on the server: one URI provides read-only, public access, the other provides authenticated read-write access. If you're developing on an Apache server (and I assume the same is true for a lot of other servers), it's often convenient to do this by hacking the path component and using '.htaccess' files... My implementation passes Joe Gregorio's APP Test Client and Tim Bray's Atom Protocol Exerciser so I think it's ready for real world use. Feel free to give it a try on Microwave (Experimental AtomPub Server)...

See also: Atom references

Resource Reservation Protovol (RSVP) Extensions for Emergency Services
Francois Le Faucheur, James Polk (et al, eds), IETF Internet Draft

Members of the IETF Transport Area Working Group (TSVWG) released a new version of the specification "Resource Reservation Protovol (RSVP) Extensions for Emergency Services." Summary: "An Emergency Telecommunications Service (ETS) requires the ability to provide an elevated probability of session establishment to an authorized user in times of network congestion (typically, during a crisis). When supported over the Internet Protocol suite, this may be facilitated through a network layer admission control solution, which supports prioritized access to resources (e.g., bandwidth). These resources may be explicitly set aside for emergency services, or they may be shared with other sessions. This document specifies extensions to the Resource reSerVation Protocol (RSVP) that can be used to support such an admission priority capability at the network layer. Note that these extensions represent one possible solution component in satisfying ETS requirements. Other solution components, or other solutions, are outside the scope of this document. The mechanisms defined in this document are applicable to controlled environments formed by either a single administrative domain or a set of administrative domains that closely coordinate their network policy and network design. The mechanisms defined in this document can be used for a session whose path spans over such a controlled environment in order to elevate the session establishment probability through the controlled environment, thereby elevating the end to end session establishment probability."

Developing a CICS-Based Web Service
G. Subrahmanyam, G. Mokhasi, S. Kusumanchi; SOA World Magazine

Web services have opened opportunities to integrate the applications at an enterprise level irrespective of the technology they have been implemented in. IBM's CICS transaction server for z/OS v3.1 can support web services. It can help expose existing applications as web services or develop new functionality to invoke web services. One of the commonly used protocols for CICS web services is SOAP for CICS. It enables the communication of applications through XML. It supports as a service provider and service consumer independent of platform and language. SOAP for CICS enables CICS applications to be integrated with the enterprise via web services as part of lowering the cost of integration and retaining the value of the legacy application. SOAP for CICS also comes along with the implementation encoder and decoder. This article describes two cases where CICS acts as a service provider and also as a consumer for complex datatype objects. CICS SOAP 1.2 is the SOAP implementation and encoding and decoding is done by the PIPELINE programs. Two exclusive PIPELINEs need to be defined, one for the provider and the other for the consumer. IBM provides CICS Web Services Assistants, namely, DFHLS2WS and DFHWS2LS. The DFHLS2WS utility takes a language data structure used by the service provider and generates the WSDL and WSBIND files. The WSBIND file is used at runtime to convert a SOAP body to a language data structure and vice-a-versa. The DFHWS2LS takes the WSDL provided by a service and generates the language data structure and a WSBIND file. Complex data types are handled by these utilities. The languages supported by these utilities include COBOL, Java, C++, and PL1. The web services are registered in the CICS region using the PIPELINE SCAN command... With the increasing demand for integration of enterprise applications with complex data type structures that have an advantage for manipulating large and complex data, developers have looked at various options one of which is web services. In this article, we have developed a CICS-based program to act as web service provider and consumer using complex data types.

Letter to Obama: Consider Open Source
Jeffrey Schwartz, Application Development Trends

The Collaborative Software Initiative (CSI) today posted an open letter to U.S. President Barak Obama on open source software. The letter urges him to mandate that the U.S. government consider open source software for federal IT initiatives. The letter was signed by top executives of companies with a vested interest in open source, including Alfresco, Ingres, Jaspersoft, OpenLogic and Unisys Open Source Business. It was subsequently signed by several dozen others. "We urge you to make it mandatory to consider the source of an application solution (open or closed) as part of the government's technology acquisition process, just as considering accessibility by the handicapped is required today (as defined by section 508)," the letter said. CSI helps companies and public organizations build solutions based on open source software and methodologies. For example, the CSI-supported TriSano effort is an open source system designed to support infectious disease surveillance and outbreak management. The letter was the brainchild of David Christiansen, a CSI senior developer, who decided to write the letter upon reading that creating electronic medical records was a priority for the president. In an interview on Tuesday, Christiansen emphasized that the letter is not intended to suggest that open source software be required. Instead, CSI's view is that open source should be considered in RFPs and federally funded programs.


SEARCH \| ABOUT \| INDEX \| NEWS \| CORE STANDARDS \| TECHNOLOGY REPORTS \| EVENTS \| LIBRARY

Headlines

Sponsors