JavaScript Cloud Native Development Cookbook

How it works...

Event Sourcing facilitates idempotence because events are immutable. The same event with the same unique ID can be published or processed multiple times with the same outcome. The micro event store serves as a buffer that weeds out duplicates. The service consumes desired events and stores them in a micro event store with a hashkey that groups related events, such as the uow.event.thing.id of the domain object, and a range key based on the uow.event.id. This primary key is also immutable. As a result, the same event can be saved multiple times, but only a single event is produced on the database stream. Thus, the business logic, which is discussed in the Creating a micro event store or Implementing an analytics BFF recipe, ...