Design Patterns and Microservices for Reengineering of Legacy Web Applications

Financial management system (FMS) is a software application that enables any organization to manage its income and expenses with the goal of maximizing profits and making the system long-lasting. FMS performs business activities like invoicing and billing with minimal accounting errors. In this research work, we have taken up Andhra Pradesh Government legacy FMS package as a case study for the diagnosis of its rudimentary code and its characterization for the poor performance. Our investigation revealed various design anomalies that are spread across multiple modules of FMS. In order to fix the performance problems, we have adapted the Mikado graphs-driven sprint methodology and reengineering approach to redesign the codebase. The fundamental goal of this research is to identify and incorporate suitable design patterns to improve the reliability and extendability parameters. The other major contribution of this research work is about modernizing the FMS through refactoring and restructuring. Strangler fig pattern-driven microservices architecture is implemented, and the resulting product is referred to as pattern-oriented FMS(PoFMS). The solution offered by this research work reduces the CAPex and OPex components of the FMS project and improved its business capabilities.