Human-in-the-Loop Large-Scale Model Transformations with the VICToRy Debugger

By: Nils Weidmann, Enes Yigitbas, Anthony Anjorin, Ankita Srivastava, Jane Jose

Abstract

Model-Driven Engineering (MDE) is an approach to software engineering with a well-defined formal basis and rich tool-support. For MDE tools to be actually usable by practitioners in industry, adequate debugging facilities must be provided. This is especially true for model transformation tools, which are often declarative in the sense that they intentionally hide low-level details such as the exact order of pattern matching and rule selection. Building debuggers for such tools is challenging, as users require enough information to locate and understand problematic parts, but do not want to be swamped with the technical bits and pieces of a transformation possibly consisting of hundreds of steps. In this paper, we report on our continued research on the VICToRy debugger, a debugger for rule-based bidirectional model transformation tools. After presenting the general idea for VICToRy in prior work, we focus in this paper on closing two gaps we have observed in research: (i) exploring how best to support breakpoints as a means of efficiently debugging large-scale human-in-the-loop model transformations, and (ii) how to debug the propagation of concurrent updates between multiple models, i. e., concurrent model synchronisation. Both features allow the user to actively interact with the transformation tool: the former by switching between manual and automated selection and application of rules, the latter by involving the user in the choice of conflicting rule applications. We provide a qualitative evaluation of these extensions indicating that supporting breakpoints does indeed make the debugger more accessible to users, and that we addressed the most important requirements for debugging concurrent model synchronisation.

Keywords

model transformation, visual debugging, consistency management.

Cite as:

Nils Weidmann, Enes Yigitbas, Anthony Anjorin, Ankita Srivastava, Jane Jose, “Human-in-the-Loop Large-Scale Model Transformations with the VICToRy Debugger”, Journal of Object Technology, Volume 21, no. 3 (July 2022), pp. 3:1-15, doi:10.5381/jot.2022.21.3.a8.