Analyzing Consistency of Behavioral REST Web Service Interfaces

TL;DR

This paper presents a method to analyze the consistency of behavioral REST web service interfaces by defining resource and behavioral models with UML and using reasoning tools to verify their validity.

Contribution

It introduces a UML-based approach to model and verify the consistency of resource and behavioral models in REST web services.

Findings

State invariants can identify inconsistent service states

Reasoning tools can verify model consistency

Ensures valid service interface design

Abstract

REST web services can offer complex operations that do more than just simply creating, retrieving, updating and deleting information from a database. We have proposed an approach to design the interfaces of behavioral REST web services by defining a resource and a behavioral model using UML. In this paper we discuss the consistency between the resource and behavioral models that represent service states using state invariants. The state invariants are defined as predicates over resources and describe what are the valid state configurations of a behavioral model. If a state invariant is unsatisfiable then there is no valid state configuration containing the state and there is no service that can implement the service interface. We also show how we can use reasoning tools to determine the consistency between these design models.