== What is this app?
This is an example of a Spring Cloud Stream processor using Kafka Streams support.
This example is a Spring Cloud Stream adaptation of this Kafka Streams sample: https://github.com/confluentinc/kafka-streams-examples/blob/4.0.0-post/src/test/java/io/confluent/examples/streams/StreamToTableJoinIntegrationTest.java
The application uses two inputs - one KStream for user-clicks and a KTable for user-regions.
Then it joins the information from stream to table to find out total clicks per region.
=== Running the app:
Go to the root of the repository.
`docker-compose up -d`
`./mvnw clean package`
`java -jar target/kafka-streams-table-join-0.0.1-SNAPSHOT.jar`
`docker exec -it kafka-join /opt/kafka/bin/kafka-console-consumer.sh --bootstrap-server 127.0.0.1:9092 --topic output-topic --key-deserializer org.apache.kafka.common.serialization.StringDeserializer --value-deserializer org.apache.kafka.common.serialization.LongDeserializer --property print.key=true --property key.separator="-"`
Run the stand-alone `Producers` application to generate some data and watch the output on the console consumer above.