Legacy Web Application Modernization by Generating a REST Service Layer

Web 2.0 phenomenon, REST services and growing mobile service consumption, among other factors, are leading the development of web applications to a new paradigm, named cross-device web application. Those web sites let organizations of all sizes provide a pervasive and contextual access to their information and services, to customers, employees and partners via potentially any kind of device. Most organizations often possess legacy systems that should face an ongoing evolution process to enhance its accessibility and interoperability. Yesterday they had to evolve to provide the user with a Web layer, and now they should evolve again to adapt to the new ways of data and services consumption on the Web. In such scenario, REST services play a key role, defining the interaction layer between the legacy system and all its heterogeneous front ends. This work presents a model-driven approach to derive a REST service layer from a legacy web application within the frame defined by a modernization process. This approach departs from a conceptual model of the legacy application generated by reverse engineering techniques. In this work we detail the generation process and provide a sample implementation instrumenting one of the studied web development frameworks to evaluate the suitability of the approach.