A Framework for Testing Semantic Web Services Using Model Checking

Web Services (WS), which are based on standard XML protocols, such as, WSDL, SOAP and UDDI, are the building blocks of Service Oriented Architecture (SOA). The aim of SOA is to automate web service tasks, such as, web service discovery, selection, composition and execution. Since XML is a syntax-based language, the automation of these tasks is still a challenge. To overcome this, web services can be described semantically using an ontology description language, e.g., Web Ontology Language (OWL), giving rise to semantic web services (SWS). Because semantic web services are relatively new, there has been little research into testing and quality assurance aspects. In this paper, we propose a novel approach for generating test cases based on user requirements for testing semantic web services. In SWS frameworks, such as, Web Service Modelling Ontology (WSMO), the user requirements are presented as a goal specification in terms of a state model. We use a model checking approach to generate test cases from this state model. To achieve this, we represent a set of rules for translation from a goal specification to a formal B abstract state machine. The B representation of the goal specification is given as input to the model checker to generate concrete test cases using the assertion violation property of the model checker. Finally, the proposed framework is evaluated using a real world case study based on, the Amazon E-commerce Service.