In this course you will learn how to create Spring Boot microservices that comply to the CQRSand Event Sourcing patterns.

You will not use any CQRS framework, but you will write every line of code that is required to effectively create your own CQRSand Event Sourcing framework using Java and Apache Kafka. While this might sound a little daunting, you will be carefully guided step by step, and gain all the know-how and confidence to become an expert in CQRSand Event Sourcing.

By the end of this course you will know how to:

• Handle commands and raise events.

• Use the mediator pattern to implement command and query dispatchers.

• Create and change the state of an aggregate with event messages.

• Implement an event store / write database in MongoDB.

• Create a read database in MySQL.

• Apply event versioning.

• Implement optimistic concurrency control.

• Produce events to Apache Kafka.

• Consume events from Apache Kafka to populate and alter the read database.

• Replay the event store and recreate the state of the aggregate.

• Separate read and write concerns.

• Structure your code using Domain-Driven-Design best practices.

• Replay the event store to recreate the entire read database.

• Replay the event store to recreate the entire read database into a different database type - PostgreSQL.

The ultimate goal of this course is to take a deep-dive into the world of CQRS and Event Sourcing to enable you to create microservices that are super decoupled and extremely scalable.