Programming Distributed Adaptive Applications: A Choreographic Approach

We present AIOCJ, a choreographic language for programming microservice-based applications which can be updated at runtime. The compilation of a single AIOCJ program generates the whole set of distributed microservices that compose the application. Adaptation is performed using adaptation rules. Abstractly, each rule replaces a pre-delimited part of the program with the new code contained in the rule itself. Concretely, at runtime, the application of a rule updates part of the microservices that compose the application so to match the behavior specified by the updated program. Thanks to the properties of choreographies, the adaptive application is free from communication deadlocks and message races even after adaptation.