kafka-streams-flatmap-values

Kafka Streams FlatMap Values

This module demonstrates the following:

• The usage of the Kafka Streams DSL, including flatMapValues() and peek().
• Unit testing using the Topology Test Driver.

In this module, records of type <String, KafkaPerson> are streamed from a topic named PERSON_TOPIC. The following tasks are performed:

1. Map the KafkaPerson value to extract both the first name and last name.
2. Flatten the resulting values.
3. Write the flattened values into a new topic named PERSON_FLATMAP_VALUES_TOPIC.

Requirements

To compile and run this demo, you will need the following:

• Java 21
• Maven
• Docker

Running the Application

To run the application manually, please follow the steps below:

• Start a Confluent Platform in a Docker environment.
• Produce records of type <String, KafkaPerson> to a topic named PERSON_TOPIC. You can use the producer person to do this.
• Start the Kafka Streams.

To run the application in Docker, please use the following command:

docker-compose up -d

This command will start the following services in Docker:

• 1 Zookeeper
• 1 Kafka broker
• 1 Schema registry
• 1 Control Center
• 1 producer person
• 1 Kafka Streams flatmap values