A Saga Pattern Microservice Reference Architecture for an Elastic SLO Violation Analysis

Reference architectures are becoming increasingly popular for industry and researchers as benchmark solutions to test their novel concepts and tools. While many reference architectures exist in the microservice domain, they are often not built on state-of-the-art technologies. Furthermore, many existing reference architectures do not use lightweight and asynchronous communications, such as messaging, do not have out-of-the-box self-adaptation and do not consider state-of-the-art microservice patterns. Therefore, this paper proposes a self-adaptive microservice reference architecture that implements the microservice saga pattern. The architecture is implemented in Java Spring Boot and uses the Eventuate Tram framework for the saga orchestration. Moreover, the architecture is instrumented to export performance metrics for monitoring and data for system-wide tracing to check for correct execution of the system and its adaptations. The objective of this reference architecture is to provide a benchmark for explaining self-adaptation and propagation of service-level objective (SLOs) violations across an architecture with complex patterns. In addition to the architecture, we provide defined SLOs and load profiles to stress the architecture.