From Monolithic Architecture Style to Microservice one Based on a Semi-automatic Approach

Due to its tremendous advantages, microservice architectural style has become an essential element for the development of applications deployed on the cloud and for those adopting the DevOps practices. Nevertheless, while microservices can be used to develop new applications, there are monolithic ones, that are not well adapted neither to the cloud nor to DevOps. Migrating these applications towards microservices appears as a solution to adapt them to both. In this context, we propose an approach aiming to achieve this objective by focusing on the step of microservices identification. The proposed identification, in this paper, is based on an analysis of the relationships between source code elements, their relationships with the persistent data manipulated in this code and finally the knowledge, often partial, of the architect concerning the system to migrate. A function that measures the quality of a microservice based on its ability to provide consistent service and its interdependence with others microservice in the resulting architecture was defined. Moreover, the architect recommendations are used, when available, to guide the identification process. The conducted experiment shows the relevance of the obtained microservices by our approach.