MAINTAINING A GRASP on Web services development platforms and environments can be a challenge. To help developers remain familiar with these innovations, IBM has released the next iteration of its alphaWorks tools, WSTK (Web Services Toolkit) 3.01, available free from the alphaWorks Web site ( www.alphaworks.ibm.com ).
This Web Services Toolkit includes run-time platforms and utilities for services-based development, delivery, and consumption, including: the WebSphere Application Server (MicroEdition); a private UDDI (Universal Description, Discovery, and Integration) registry for local test publishing and lookup of services; and several demos and tutorials to highlight the plentiful new capabilities.
We found the most interesting features in this release to be the technology previews, which are the next wave of products and standards maturing to address many of the deficiencies in services-oriented architectures. Among them is Axis, an alpha version of the new Apache SOAP (Simple Object Access Protocol) 3 implementation; HTTPr, the next-generation protocol for HTTP-based messaging; security functions for digital signatures and encrypted payloads in SOAP; and a new class of pluggable utilities for, among other possibilities, metering and billing for services usage.
What this product lacks is a comprehensive Web services deployment platform or graphical development IDE (integrated development environment). In fact, IBM has removed tools, such as the Web Services Tooling for EJBs (Enterprise JavaBeans), that came with previous versions of the kit. Now tools are included in commercial products such as IBM's WebSphere Studio Application Developer. But that level of support is not the intention of this toolkit. The alphaWorks tools are delivered as-is, free of charge, to provide an advance look at new functionality.
The wizard-driven installation shield deployed easily and the configuration utility made the process of readying our Web services environment uncomplicated.
The toolkit's Web services stack includes a lightweight version of the WebSphere 4.0 application server, and XML processing support brought by Apache XML utilities such as Xerces and Xalan. But for any additional capabilities -- such as support for EJB 1.1, transaction management, connection pooling, or performance monitoring -- you will need to look elsewhere.
Furthermore, the UDDI (Universal Description, Discovery, and Integration) implementation is a lightweight rendition that cannot be used with any application servers outside this Web services stack.
However, the configuration wizard helped to set dependencies in the runtime stack environment and can configure use with the full-blown WebSphere application server as well as Jakarta Tomcat 4.
Although setup was easy, we felt the kit could benefit from some additional shortcuts for quick access to tasks such as starting of the Web services stack and UDDI registry, for example.
In addition to server-side components, the kit contains a number of client-side APIs for accessing the UDDI registry and WSDL (Web Services Description Language) documents. WSTK also implements the relatively new WSIL (Web Services Inspection Language) that allows Web services to be discovered straight from a Web server URL, bypassing the need for a UDDI lookup.