Hands-On Reactive Programming in Spring 5

Sharing data across microservices

In real business systems, it is often required to query data owned by two or more services in order to process a client request. For example, a client may want to see all their orders and the payment statuses corresponding to their orders. Before the microservices architecture, this could be implemented with a single join query, but now this is against best practices. To handle a multi-service request, it is required to implement an adapter service that queries both order and payment services, applies all required transformations, and returns an aggregated result to the client. Also, it is quite evident that if two services communicate a lot or highly depend on each other, they may be the right candidates ...