Integrations with databases and message brokers

Stateful services need a datastore. You can store state using Event Sourcing or CRUD (Create, Read, Update, Delete). The example in the tutorial demonstrates the Event Sourcing option. The tutorial uses PostgreSQL for storing the events and creating a Projection for queries. An alternative to using an RDBMS is described in Use Cassandra instead of PostgreSQL. For more details on migrating your model from CRUD to Event Sourcing review How to migrate from CRUD to Event Sourcing.

To decouple communication between different Microservices, you can publish messages to a broker, such as Apache Kafka. The tutorial illustrates how to use Apache Kafka in a projection publishing to Kafka. See Internal and External Communication concepts for more information.

Data store integrations

You can find examples of data store integrations on the following pages:

Message broker integrations

You can find examples of message broker integrations on the following pages: