Transactional composite applications

Composite applications leveraging the functionalities offered by Web services are today the underpinnings of enterprise computing. However, current Web services composition systems make only use of functional requirements in the selection process of component Web services while transactional consistency is a crucial parameter of most business applications. The transactional challenges raised by the composition of Web services are twofold: integrating relaxed atomicity constraints at both design and composition time and coping with the dynamicity introduced by the service oriented computing paradigm. In this chapter, we present a new procedure towards automating the composition of transactional Web services. This composition procedure does not take into account functional requirements only but also transactional ones based on the Acceptable Termination States model. The resulting composite Web service is compliant with the consistency requirements expressed by business application designers and its execution can easily be coordinated using the coordination rules provided as an outcome of our approach. An implementation of our theoretical results based on OWL-S and BPEL technologies is further detailed as a proof of concept