Runtime Verification of Web Service Interface Contracts

Amazon Web Services (AWS) provides diverse services, among them the Amazon Associates Web Service (also known as the Amazon E-Commerce Service or ECS), a free service that exposes Amazon's product data with the goal of driving traffic back to the Amazon website. An Ajax application using the AWS-ECS was built, consisting of six operations. Runtime testing helped discover whether the programmer correctly understand the service implementation and check that the Web service fulfills the constraints described in its documentation. The experiments with the AWS-ECS demonstrated the advantages of using a model-based approach for the runtime testing and monitoring of Web applications. In a first step, programmers can verify their understanding of the documentation by automatically producing test sequences that are run on the actual Web service implementation. Then, BeepBeep can seamlessly and easily enforce interface contracts on the client side, warning the user of violations and preventing erroneous messages from reaching their destination.