Modélisation et Test Fonctionnel de l'Orchestration de Services Web. (Modelisation & Functional Testing of Web Services Orchestration)

Last years have seen the emergence of the service oriented architecture (SOA) designed to facilitate the creation, the publication, the networking and the reuse of applications based on services. Web services are the most important realization of the SOA architecture. They are self descriptive and modular entities which provide a simple model of programming and application deployment. Web services composition, especially orchestration, is at the heart of service oriented computing (SOC), since it supports the construction of new composite services out of basic services. WS-BPEL (BPEL for short) has emerged since 2005 as the standard language for Web service orchestration. This PhD thesis focuses on functional testing of service orchestrations described in BPEL, which aims to establish the conformance of a composite service implementation to its specification. Our research activities have been motivated by specific features of the BPEL composition, and the need for test automation. The objective of this thesis is twofold : on the one hand, to propose a formal modeling of service orchestration, and on the other hand, to propose a comprehensive testing approach for orchestrations, ranging from orchestration modeling to tests execution, including automatic test case generation. Compared to existing work, our formal model covers a large subset of BPEL constructs and focuses on the temporal properties of the composition. The formal model is a first step of our testing approach. Afterwards, we use the model to generate the test cases according to test purposes. We automate the test generation by implementing an efficient state space search strategy inside an open-source simulator, i.e. the IF simulator. In our case, to focus on the potential errors of the orchestrator, we propose a gray box approach which consists on the simulation of the partners of this orchestrator. We have addressed these issues both from a theoretical and practical perspective. Therefore, besides proposing expressive orchestration models and test case generation algorithm, we have developed prototypes (BPEL2IF and TestGen-IF) as a proof of concepts. BPEL2IF transforms a BPEL orchestration into a formal specification based on timed automata (IF specification). TestGenIF generates automatically timed test cases. Moreover, to validate our proposal, we have applied our testing approach on real size case studies.