Towards autonomic service-oriented applications

The integration of third-party web services can solve complex business problems and can reduce risks, costs and time-to-market. However, the task of the integrators is challenged by services that are maintained by different organisations, and that may evolve dynamically and autonomously. The impossibility of statically determining which service implementation will be bound at runtime may lead to unexpected failures. This paper presents a novel approach for designing self-adaptive service-oriented applications, which autonomously react to changes in the implementation of the services, automatically detect possible integration mismatches and dynamically execute suitable adaptation strategies. The solution proposed in this paper is based on a taxonomy of integration faults that helps developers anticipate potential mismatches between discovered web services and applications, and design test cases and adaptors for each mismatch. A simple tool facilitates the deployment of a runtime infrastructure that embeds the test cases and the adaptors, automatically runs the test cases against newly discovered web services, uses the test results to diagnose service mismatches and executes the adaptors to overcome the revealed problems without user intervention.