Tolerant Consistency Management in Model-Driven Engineering

Model-driven engineering (MDE) enables domain experts to specify, validate and maintain software systems without requiring advanced programming skills. An important challenge when treating models as primary artifacts in the software development process is maintaining consistency between them. Consistency management subsumes tasks such as consistency checking, model transformation and update propagation. However, strict consistency is almost impossible to achieve in practical applications and is often not even a desirable goal. For instance, small updates in a source model can lead to substantial changes in the respective target model, making automated steps incomprehensible for the user and therefore decreasing the trustworthiness of the software system. Ongoing research explores how to deal with inconsistency while still guaranteeing formal properties. However, conceptual and practical work on systems that tolerate inconsistencies to a certain extent is rather sparse. To the best of our knowledge, there is no MDE tool which supports all consistency management tasks mentioned before in a tolerant manner. This short paper provides a roadmap for possible approaches to address the problem of handling inconsistencies with help of bidirectional transformation (bx) tools. The bx tool eMoflon will be taken as a concrete example to demonstrate the theoretical concepts. It uses Triple Graph Grammars (TGGs) as an underlying formalism to express the consistency relation between source and target models.