Correct-by-Construction Web Service Architecture

Service-Oriented Computing aims to facilitate development of large-scale applications out of loosely coupled services. The service architecture sets the framework for achieving coherence and interoperability despite service autonomy and the heterogeneity in data representation and protocols. Service-Oriented Architectures are based on standardized service contracts, in order to infuse characteristic properties (stateless interactions, atomicity etc). However, contracts cannot ensure correctness of services if essential operational details are overlooked, as is usually the case. We introduce a modeling framework for the specification of Web Service architectures, in terms of formal operational semantics. Our approach aims to enable rigorous design of Web Services, based on the Behaviour Interaction Priorities (BIP) component framework and the principles of correctness-by construction. We provide executable BIP models for SOAP-based and RESTful Web Services and for a service architecture with session replication. The architectures are treated as reusable design artifacts that may be composed, such that their characteristic properties are preserved.