Book Image

Event-Driven Architecture in Golang

By : Michael Stack
5 (1)
Book Image

Event-Driven Architecture in Golang

5 (1)
By: Michael Stack

Overview of this book

Event-driven architecture in Golang is an approach used to develop applications that shares state changes asynchronously, internally, and externally using messages. EDA applications are better suited at handling situations that need to scale up quickly and the chances of individual component failures are less likely to bring your system crashing down. This is why EDA is a great thing to learn and this book is designed to get you started with the help of step-by-step explanations of essential concepts, practical examples, and more. You’ll begin building event-driven microservices, including patterns to handle data consistency and resiliency. Not only will you learn the patterns behind event-driven microservices but also how to communicate using asynchronous messaging with event streams. You’ll then build an application made of several microservices that communicates using both choreographed and orchestrated messaging. By the end of this book, you’ll be able to build and deploy your own event-driven microservices using asynchronous communication.
Table of Contents (18 chapters)
1
Part 1: Event-Driven Fundamentals
5
Part 2: Components of Event-Driven Architecture
12
Part 3: Production Ready

Tracking Changes with Event Sourcing

In the previous chapter, our MallBots application was updated to use events to communicate the side effects of changes to other parts of a module. These domain events are transient and disappear once the process ends. This chapter will build on the previous chapter’s efforts by recording these events in the database to maintain a history of the modifications made to the aggregate.

In this chapter, we will be updating our domain events to support event sourcing, add an event sourcing package with new types, and create and use Command and Query Responsibility Segregation (CQRS) read models projected from our domain events. Finally, we will learn how to implement aggregate snapshots. Here is a quick rundown of the topics that we will be covering:

  • What is event sourcing?
  • Adding event sourcing to the monolith
  • Using just enough CQRS
  • Aggregate event stream lifetimes

By the end of this chapter, you will understand how...