Using Test Cases as Contract to Ensure Service Compliance Across Releases

摘要

Web Services are entailing a major shift of perspective in software engineering: software is used and not owned, and operation happens on machines that are out of the user control. This means that the user cannot decide the strategy to migrate to a new version of a service, as it happens with COTS. Therefore, a key issue is to provide users with means to build confidence that a service ⅰ) delivers over the time the desired function and ⅱ) at the same time it is able to meet Quality of Service requirements. This paper proposes the use of test cases as a form of contract between the provider and the users of a service, and describes an approach and a tool to allow users running a test suite against a service, to discover if functional or non-functional expectations are maintained over the time. The approach has been evaluated by applying it to two case studies.