Sample Kafka Streams in Kotlin using:

• Json Serde using Kotlin reified
• There is a Avro version of the Kafka Streams too
• A Topology with a Transformer, and a state, to prevent sending duplicate downstream
• JUnit 5 tests using TopologyTestDriver

The program:

• Rely on localhost:9092
• creates the necessary topics (in and out) if necessary (using the AdminClient)
• produce random data in the input topic every seconds

If you look in Conduktor, you will see 3 topics with data: