A model driven approach for service based system design using interaction templates
Autori
Viac o knihe
Based on the increasing complexity of modern avionics, the associated system design processes moved towards Model Driven Architecture (MDA) based processes. Additionally, the demand for higher system autonomy features requires means to further modularise mission systems and to define and establish interactions among the systems’ individual components. Therefore, the ideas of service-oriented computing are currently adapted to established, model driven design processes. With respect to modelling interactions for service components, current approaches are limited to only a fixed set of communication primitives, restricting a service designer’s expressiveness to specify service interaction. In consequence, interaction patterns not included in this basic set have to be reflected in application code, mangling application and communication logic. Furthermore, when service functionality relies on communication semantics which are not provided by the underlying set of primitives, additional emulation behaviour has to be added to the service which makes this mangling even worse. Platform independence is reduced as services can not easily be ported to platforms not natively supporting the selected primitives which contradicts the ideas of model-driven development. Addressing these limitations, this thesis proposes a new model-driven service development process based on Interaction Templates (ITs), promoting interactions among service participants to first class modelling entities. The process focuses on modelling the interactions among service participants. Interaction semantics are explicitly specified in models, beyond pure stereotyping, and gain increased platform independence for services with respect to communication. The process exploits automated Model-to-Model (M2M) and Model-to-Text (M2T) transformations to assist service implementation and to automatically derive interaction realisations on concrete target platforms. This allows for easy replacement and inter-mixing of communication middleware to realise a service’s interactions. This way, services become independent of the underlying communication primitives by only relying on ITs and not platform primitives which are hidden behind ITs. In turn, realising ITs on concrete platforms is not affected by their utilisation for service interaction. Beside the novel modelling process itself, the presented work defines a Unified Modeling Language (UML) profile, referred to as UML Profile for Interaction-centric Services (UP4IS), which directly supports the adaptation of standard UML language constructs and tools for the proposed modelling approach. The whole development process is demonstrated via the specification of a simple video recording systems consisting of two services. The services themselves are based on a representative IT library which forms an essential part of the presented case study. Using these service and IT models, the thesis emphasises the necessary model transformation and code generation steps to derive service implementations based on the abstract models.