How to run this project

Requirements

• You need Docker in your machine to run this project
• This project is written in Java, because KStreams is a library only available for Java and Scala. Use IntelliJ or other IDE to run the Java project.

Kafka containers

You have to run the following command, to run the containers:

docker-compose up -d

Now you should have Kafka, Zookeepeer and KafDrop (UI for Kafka) running.

Open in your browser, the next URL:

http://localhost:9000

Now you are in Kafdrop, you have to create the following topics:

• fruits
• fruitsCounter

How to run this project

• Run the containers
• Run the Java project
• Send events to fruits topic

Use this command for sending events:

docker-compose exec kafka kafka-console-producer.sh --topic fruits --bootstrap-server localhost:9092

• In Kafdrop, you can see the topic fruitsCounter is receiving messages, but the counter is not visible.

You can run the following command to watch this events as a consumer in the terminal:

docker-compose exec kafka kafka-console-consumer.sh --bootstrap-server localhost:9092 \             
--topic fruitsCounter \
--from-beginning \
--formatter kafka.tools.DefaultMessageFormatter \
--property print.key=true \
--property print.value=true \
--property key.deserializer=org.apache.kafka.common.serialization.StringDeserializer \
--property value.deserializer=org.apache.kafka.common.serialization.LongDeserializer