Visualizing and Exploring Data Access in Microservices Using Interactive Treemaps

The popularity of microservices has grown significantly over the past decade. This architectural style is praised for its ability to ease software evolution, particularly due to the modular, heterogeneous, and dynamic communication nature of microservices. This new way of designing applications has also impacted how databases are integrated. Practitioners generally opt for polyglot persistence, meaning that each microservice manages its own database(s). Decoupling, heterogeneity, and distribution introduce implicit dependencies and multiply data access endpoints. This results in added complexity and challenges in understanding change propagation, which can only be addressed through manual browsing of the codebase, a time-consuming, error-prone, and cumbersome process. A holistic view of such architectures is essential, especially for enabling developers to understand, maintain, and optimize the complex interactions across microservices, particularly from a data perspective.We extend a visualization-based approach to support both a high-level view and fine-grained inspection of microservices. Based on static analysis, we generate an interactive treemap for an entire microservices architecture, providing both an overview and the means for more detailed exploration.We evaluated our approach by assessing the scalability and effectiveness of our visualization. First, we generated interactive treemaps for 10 non-trivial microservices architectures. Then, in a qualitative user study, we asked 6 professional developers to perform specific exploration and understanding tasks (e.g., understanding architectural structure, assessing concept spreading, evaluating technology breakdown, comparing versions, identifying anti-patterns). Our results show that interactive treemaps provide the holistic view needed to aid in evolution tasks.