In this week’s CTO Tuesday, I addressed the question of whether the architectural style called “REST” is well suited to BPM. I’ll save you the suspense and tell you the answer is no. That isn’t to say that ActiveVOS doesn’t support REST. It does. But if you have a choice, should you follow that style? That is where the answer is no.

Contrary to many of the APIs that call themselves REST-based, REST means more than using HTTP GET to call the service and getting plain XML documents back as results. The talk describes the five key principals of REST, including the most important one, which is called HATEOAS. It is an interesting principal that works well for the Web, but it is antithetical to design-time type checking. In fact the REST style is, in general, in conflict with any kind of design-time typing (Roy Fielding refers to typing as “out-of-band” information that creates a tight coupling between client and server).

However, design-time typing is just part of a well-defined service contract and good service contracts are one of the most important characteristics of a service-oriented architecture. I describe this more fully in the talk and also describe the critical value of design-time typing for BPM. I also show how fragile business processes become when they have to depend on REST.

You can view the talk using one of the formats below or just look at the slides (the PDF at the bottom).

Tags: BPM, CTO Tuesdays, HATEOAS, rest, SOA

This entry was posted on Wednesday, August 11th, 2010 at 2:18 pm and is filed under BPM, BPMS, CTO, CTO Tuesdays, SOA, iTunes. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.