Api Slicer: A Feature-Based Approach to Decomposing Monolithic Apis into Microservices

Many approaches related to decomposing monolithic applications have been proposed in recent studies. However, such studies are not sensitive to the decomposition of Monolithic APIs into microservices, resulting in the manual decomposition of monolithic APIs, based solely on the developer's experience. This article introduces the API Slicer, a similarity level-based approach between features, which uses the execution trace to understand the monolithic API and generate suggestions for microservices. The API Slicer stands out for showing which functionalities should be transformed into microservices and which should remain in the monolithic API, being agnostic of the technology, as long as the target application is object-oriented, and the similarity is made based on the list of packages that the user provides at the beginning of the recommendation process. The new aspect of our article is the proposed feature-based approach to decompose monolithic APIs into microservices. Furthermore, we propose an intelligible workflow and an architectural model for assisting software developers in the decomposition of monolithic APIs. Developers benefit from the API Slicer because it allows the semi-automatic decomposition of a monolithic API. The approach was evaluated through a case study, where 3 target applications were tested to verify the effectiveness of the microservice recommendation.