Lukas Renggli, Stéphane Ducasse, Adrian Kuhn. Magritte - A Meta-driven Approach to Empower Developers and End Users. In Gregor Engels, Bill Opdyke, Douglas C. Schmidt, Frank Weil, editors, Model Driven Engineering Languages and Systems, 10th International Conference, MoDELS 2007, Nashville, USA, September 30 - October 5, 2007, Proceedings. Volume 4735 of Lecture Notes in Computer Science, pages 106-120, Springer, 2007. [doi]
Developing applications that end users can customize is a challenge, since end users are domain experts but still have concrete requirements. In this master thesis we present how we used a meta-driven approach to support the end user customization of Web applications. We present Magritte, a recursive meta-data meta-model integrated into the Smalltalk reflective meta-model. The adaptive model of Magritte enables to not only describe existing classes but also let end users build their own meta-models on the fly. Further on we describe how meta-interpreters automatically build views, reports, validating editors and persistency mechanisms. As a complete example of how we applied a meta-model to a Web application we present Pier, the second version of a fully object-oriented implementation of a content management system and Wiki engine. Pier is implemented with objects from the top to the bottom and is designed to be customizable to accommodate new needs. The integration of a powerful meta-description layer makes it a breeze to extend the running system with new functionality without having to patch the core engine. We describe the lessons learned from using the Magritte meta-model to build applications. Both projects described in this thesis are open source and can be downloaded from the Web site of the author.