Towards Semantics Driven Generation of Executable Web Services Compositions

Web services composition is a very active area of research due to the growing interest of public and private organizations in services integration and/or low cost development of value added services. The problem of building an executable web service from a service description has many faces since it involves web services discovery, matching, and integration according to a composition process. In this paper we propose a life cycle for the automated composition of web services which is based on the usage of Domain Ontologies for the description of data and services, and on workflow patterns for the generation of executable processes. In particular the paper focuses on the integration of the matching and composition phases. The approach aims at producing executable processes that can be formally verified and validated. This is achieved by exploiting formal definitions of composition rules and of BPEL4WS constructs. These definitions are expressed in operational semantics and are translated into Prolog programs in order to be throughout the composition process. A reference architecture for implementing the proposed life cycle is also describe