An approach to metamorphic testing for WS-BPEL compositions

Nowadays, Web Service (WS) compositions play an important role in business processes. Languages for composing web services, such as the OASIS WS-BPEL 2.0 standard, open a new field for large-scale programming. However, they also present a challenge for traditional quality assurance because of the inclusion of specific instructions for concurrency, fault compensation, and dynamic service discovery and invocation. Metamorphic Testing (MT) has proved useful to test and improve the quality of traditional imperative programs. This paper discusses how to use MT to test WS compositions in WS-BPEL. Although MT has not been previously applied to this area, promising results have been obtained in a number of different applications. A component diagram for a testing framework implementing this approach is included.