Generic disclaimer: This is a general checklist and the specific steps for your project may vary based on the complexity and scale of your system.
- Define the events: Identify the actions that take place in the system, such as "user created", "order placed", etc. These actions will be the events that drive the system.
- Separate Read and Write models: Divide the existing CRUD models into separate read and write models to reflect the separation of concerns in a CQRS architecture.
- Create Event Store: Store the events that occur in the system in a central event store.
- Implement Command Handlers: Write handlers for each command that maps to an event and stores it in the event store.
- Implement Event Handlers: Write handlers for each event that updates the read model and any relevant domain entities.
- Create Query Handlers: Write handlers for each query that retrieves data from the read model.
- Update API: Update the API to use commands and queries instead of CRUD operations.
- Test and Validate: Test the system to make sure all the changes work as expected and validate the read and write models.
- Deploy: Deploy the refactored event-driven CQRS system.
- Monitor and Improve: Monitor the system for any issues and continuously improve it to meet evolving needs.