A Model-Driven Approach to Discovery, Testing and Monitoring of Web Services

Service-oriented computing is distinguished by its use of dynamic discovery and binding for the integration of services at runtime. This poses a challenge for testing, in particular, of the interaction between services. We propose a model-driven solution to address this challenge. Service descriptions are promoted from largely syntactical to behavioural specifications of services in terms of contracts (pre-conditions and effects of operations), expressed in a visual UML-like notion. Through mappings to semantic web languages and the Java Modeling Language (JML) contracts support the automatic discovery of services as well as the derivation of test cases and their execution and monitoring. We discuss an extended life cycle model for services based on the model-driven approach and illustrate its application using a model of a hotel reservation service.