Automatic production of transformation chains using structural constraints on output models

Model transformations are usually difficult to automate as they require to transform graphs into other graphs while the result must respect a set of predefined constraints. In previous works, we described how to compose competing model transformations addressing the same objective with different non-functional results. In this paper, we focus on the composition of complementary transformations addressing different needs. In particular, the order in which model transformations are applied must be determined when they are not commutative. However, preconditions and post conditions must still be valid and the evaluation of chains alternatives can be time consuming. We propose to solve this problem by abstracting models, transformations, and chaining process with a formal logic in order to fasten the discovery of valid transformation chains. Our solution first translates model transformations as Alloy constrained binary relations between input and output models and second exhibits a valid chain of transformations.