Enterprises in their journey to the cloud, want to decompose their monolith applications into microservices to maximize cloud benefits. Current research focuses a lot on how to partition the monolith into smaller clusters that perform well across standard metrics like coupling, cohesion etc. However, there is little research done on taking the partitions, identifying their dependencies between the microservices, exploring ways to further reduce the dependencies, and making appropriate code changes to enable robust communication without modifying the application behaviour.

In this work, we discuss the challenges with the conventional techniques of communication using JSON and propose an alternate way of ID-passing via APIs. We also devise an algorithm to reduce the number of APIs. For this, we construct subgraphs of methods and their associated variables in each class, and relocate them to their more functionally aligned microservices. Our experiments and qualitative study on five public Java applications clearly demonstrate that our refactored microservices using ID approach have decidedly better time and memory complexities than JSON and reduces 40-60% of the manual refactoring efforts.