Towards UML Modelling Extra-Functional Properties in Web Services and their Clients

Web Services provide our systems with a platform independent and loosely coupled implementation environment, being time to face how the named systems can be modelled. Service Component Architecture (SCA) allows us to define services independently of the final implementation technology; however, it does not integrate the remaining development stages. Model Driven Architecture provides a method to face all stages in development from the platform independent model to final code, although it is not specific to service technologies. Regarding web service extra-functional properties, WS-Policy establishes how to describe them in a loosely coupled manner; however the loosely coupled environment is not always maintained when modelling or implementing these properties, which can be solved by using aspect-oriented techniques. In this paper, we propose to use a model driven approach for extra-functional properties in SCA service based models, where generated code will consist of the policy description and an aspect-oriented implementation.