JavaScript Cloud Native Development Cookbook

Creating a micro event store

In the Creating a data lake recipe, we will discuss how the Event Sourcing pattern provides the system with an audit trail of all the state-change events in the system. An event stream essentially provides a temporal event store that feeds downstream event processors in near real-time. The data lake provides a high durability, perpetual event store that is the official source of record. However, we have a need for a middle ground. Individual stream processors need the ability to source specific events that support their processing requirement. In this recipe, we will implement a micro event store in AWS DynamoDB that is owned by and tailored to the needs of a specific service.