BPEL conformance in open source engines

Measuring the Portability of Executable Service-Oriented Processes

“…If all runtimes available support all of the language elements available in the same manner with respect to semantics, then any compilable program will be portable to any runtime and there are no portability issues. Language runtimes for Java come close to this property, but for BPEL and serviceoriented process languages in general, the situation is rather different, as demonstrated in recent benchmarks [10]. There, each runtime typically supports a specific language subset, as outlined in Fig.…”

“…In [10], even the top three engines in terms of successful conformance tests share only 45 % of the total test set. This implies that engines implement relatively disjoint sets of the language (cf.…”

“…The Web Services Business Process Execution Language (BPEL) [7], which can be used to build stateful services by orchestrating other services using a control-and data-flow definition between the different invocations, provides a platform-independent format and has attracted a huge amount of interest in serviceoriented computing. In previous work [10], we presented a tool for benchmarking BPEL engines and could show that current engines are limited in terms of their support for the language specification and the portability of process definitions among them cannot be taken for granted. As a consequence, even services that are designed to be portable by being implemented in BPEL, tend not to be so.…”

“…Thus, we support the development of portable process definitions. We define, formalize and validate a set of metrics for assessing process definitions, in contrast to engines as in [10]. Benchmarking results from the tool are one of several factors fed into the metrics computation (cf.…”

“…section III). Finally, the data set used in this paper is a considerable extension of the data underlying [10], by roughly 30%. Although we build on BPEL, the approach we take for measurement and the metrics we propose are independent of it and applicable to service-oriented processes in general.…”