Formal Verification of Stateful Services with REST APIs Using Event-B

REST APIs are being increasingly used in the industry including their application in safety-critical domain and in the IoT world. They offer basic CRUD (create, retrieve, update and delete) interfaces. However, REST APIs can be used to build services with more advanced scenarios. Developing such services with REST constraints requires rigorous approaches that are capable of creating services that can be trusted for their behavior. In this work, we present an approach based on formal verification technique for a development of REST services using Event-B. We focus on deriving a correct system architecture by refinement and consistency verification of service design models. We illustrate our approach on a Hotel Reservation System.