Patterns for Service-Oriented Architectures

DW Article series on SOA patterns

IBM's James Snell has a series of articles on SOA patterns. Part 1 talks about the 'asynchronous query pattern' and Part 2 covers the 'command facade pattern'.

Web Services Integration Patterns

Massimiliano Bigatti, in his article on xml.com, introduces some design patterns applicable to Web service that his team came across while developing an application for the banking industry.

Facade pattern and Web services

The Facade pattern, defined by the GoF, provides a simplified/unified interface to a larger system.

The use case below explores how a Facade pattern can be implemented via a Web service interface.

SOA Blueprints: Best practices for service-oriented architectures

The Middleware Company, in conjunction with other companies like BEA, recently published an example architecture utilizing SOA best practices. This architecture is available at the SOA blueprints website (registration required). The architecture demonstrates how an example HR system/Employee portal and Product services system can be designed using SOA. It also describes (briefly) the provisioning of an enterprise wide security service to provide authentication, authorization and auditing capabilities for all enterprise applications.

IBM's Pattern website

IBM has a e-business Patterns website that really good. It classifies it's patterns as

• Business patterns
• Integration patterns
• Composite patterns
• Custom designs
• Application patterns
• Runtime patterns

Though these patterns are for Web applications, some of the runtime patterns I've looked at (and used), such as the High Availability Pattern and the High Performance Pattern are clearly applicable for Web services too.

Microsoft's Patterns and Practices

Microsoft has 'patterns & practices' websites that have catalogs of patterns. Some of them are Microsoft-centric, but many have applicability to any enterprise scenario. The websites are :

• .NET Architecture Center: Patterns
• Patterns Community
• Microsoft Patterns and Practices

There is also a useful document on Enterprise Solution Patterns Using Microsoft .NET in the MSDN library.

A great website for Enterprise Java Patterns

I'm sure every Enterprise Java developer/architect knows of this resource, but I'm listing it here nonetheless: the patterns webpage at TheServerSide.

You should subscribe to their RSS feed, if you haven't already done so. The website also has a free book and source code download for the EJB Design Patterns book that covers many of the patterns discussed there.

Web service patterns

I've started a new weblog for exploring design patterns and their applicability to Web services. I'm armed with three good books for my journey- the classic Design Patterns book by the gang-of-four (Erich Gamma, Richard Helm, Ralph Johnson, John Vlissides), Core J2EE Patterns: Best Practices and Design Strategies, Second Edition by Deepak Alur, Dan Malks and John Crupi and Patterns of Enterprise Application Architecture by Martin Fowler. Hopefully these Web service patterns should translate into the .NET world too.

My intention is to see which of these pattens are applicable to Web services (and how) and also to explore new patterns of usage.

At first glance, there are three patterns that may apply (below), and I'll be exploring these in the months to come:

• Adapter
• Facade
• Proxy