The BizTalk team announced last week the availability of the Community Technology Preview 3 of the ESB Guidance. The download is available on CodePlex, Microsoft's open source project hosting web site.
This latest release includes:
- Windows Communication Foundation (WCF) adapter integration
- Further integration into BizTalk Server 2006 R2
- Partial Request-Response support for on/off ramps (up until now the ESB guidance only supported a message sender/receiver pattern)
- Resolvers and the Adapter Provider Framework which supports policy-driven end point resolution.
- Tighter integration with key SOA Governance vendors such as Amberpoint and SOA Software.
Marty Wasznicky, Field Program Manager in the Connected System Division (CSD), comments :
Our [..] goal was to develop a robust architecture for high performance yet flexible runtime resolution and transformation at the messaging level, without the need for the existing Orchestration-based services developed in previous releases of the ESB Guidance. [...] The result is the Resolver and Adapter Provider Framework, which supports dynamic loading, caching, and invocation of registered Resolvers. The Resolver determines the end-point configuration and URI, given certain facts.
A detailed overview (functional and technical) can be downloaded from the ESB guidance community website.
The BizTalk team delivered the guidance based on Gartner's definition of an ESB:
“A Web-services-capable infrastructure that supports intelligently directed communication and mediated relationships among loosely coupled and decoupled biz components.” (Source: Gartner Group)
which translated into 5 key capabilities:
- Message brokering
- Message transformation
- Message validation
- Adaptation
- Service Orchestration
Loose-coupling is achieved via an interceptor pattern associated to both consumers and providers. This is within these interceptors that routing, transformation, validation,... occurs. Orchestration is provided by the BizTalk Server. Microsoft qualifies its architecture as an hybrid hub/bus architecture.
One of the core function of the interceptors is to decorate every message that flows through the ESB with ESB specific metadata that can be interpreted by the underlying BizTalk server.
The source code and the documentation can be downloaded here. I have heard that a VM is available (since it requires the BTS 2006 R2 beta) but could not find a pointer to download it.