A Novel Method for Identifying Microservices by Considering Quality Expectations and Deployment Constraints

Abstract

Nowadays, microservice architecture has become a dominant software development and deployment paradigm. Decomposing a system into loosely coupled, highly cohesive, and fine-grained microservices while meeting various technical constraints and implementing business capabilities is particularly important for microservice system (MS) designers. When an MS has a large number of functionalities and complex interconnections, it is a big challenge to identify microservices solely based on the experience of MS designers. We propose a structured and automated microservice identification method to decompose a system into appropriate microservices for this challenge. We model a system as unified modeling language (UML) class and sequence diagrams. In the identification phase, we take into account not only the traditional coupling-related criteria but also the quality expectation and deployment constraints, both of which have not yet been fully concerned in previous studies. Based on the criteria, a microservice identification algorithm using the clustering technique is designed. A case study of elderly care services illustrates the identification process. Experiments are conducted to evaluate and compare the proposed method against state-of-the-art methods. Results indicate that the proposed method significantly outperforms those compared from the literature.