REST and ESBs
The evolution of Representational State Transfer (REST) as an Architecture style is having a strong influence in the way developers think about to accessing and exposing data. This influence is especially notable in Service Oriented (SOA) technologies such as Service Repositories, SOA Governance Servers, Enterprise Service Buses (ESB) and Integration Servers. Particularly, Integration servers and ESBs are a natural fit for RESTful services given its applicability of data exchange scenarios. In my opinion Integration servers and ESBs will embrace REST in two fundamental ways:
- Exposing RESTful resources: Integration services and ESBs are normally composed by a set of resource-rich technologies such as Business Rules, Business Activity Monitoring, orchestration monitoring, etc. One of the main challenges of adopting those technologies is that their interfaces are often limited to a particular programming language or to a set of SOAP-based services that can only be consumed by technologies that provide rich SOAP frameworks such as WCF or J2EE application servers. Exposing RESTful interfaces to these technologies will expand their use on emerging programming paradigms such as dynamic languages, AJAX toolkits etc.
- Consuming RESTful services: Complementarily to the previous topic, integration servers and ESBs should embrace the consumption of RESTful services into technologies such as orchestrations or business rules. Although most of the integration servers and ESBs on the market provide a strong support for HTTP as a transport protocol, embracing REST entails natively supporting other Web based protocols such as Atom/AtomPub, RDF or JSON as well as a beter support or manipulating URLs. The recent release of MuleSource RESTpack it's a good example of this approach.
Although today technologies such as BizTalk Server R2 or Oracle BPEL PM provide the basic infrastructure to consume and expose RESTful services, in the near future we should see REST become a fundamental component of integration servers and ESBs.
On my next post I plan to illustrate an example of how to consume RESTful services using AtomPub from BizTalk Server.