Sample - Pub-Sub

#####Setup Zookeeper

• Download the ZooKeeper 3.7.0 from here.

• Unzip the file. Inside the conf directory, rename the file zoo_sample.cfg as zoo.cfg.

• The zoo.cfg file keeps configuration for ZooKeeper, i.e. on which port the ZooKeeper instance will listen, data directory, etc.

• The default listen port is 2181. You can change this port by changing clientPort.

• The default data directory is /tmp/data. Change this to ../data, as you will not want ZooKeeper's data to be deleted after some time. Create a folder with the name data in the ZooKeeper directory.

• Go to the bin directory.

• Start ZooKeeper by executing the command zkServer. or zkServer.sh start (on mac os).

#####Setup Kafka Server

• Download the latest stable version of Kafka from here.

• Unzip this file. The Kafka instance (Broker) configurations are kept in the config directory.

• Go to the config directory. Open the file server.properties.

• Remove the comment from listeners property, i.e. listeners=PLAINTEXT://:9092. The Kafka broker will listen on port 9092.

• Check the zookeeper.connect property and change it as per your needs. The Kafka broker will connect to this ZooKeeper instance.

• Go to the Kafka home directory and execute the command .\bin\windows\kafka-server-start.bat .\config\server.properties (on windows) or ./bin/kafka-server-start.sh config/server.properties (on macos).

d We will need to create a topic on kafka to store messages for bank transactions. Please execute the following command to create a topic named sample.

./kafka-topics.bat --create --topic sample --bootstrap-server localhost:9092

You can monitor the Kafka server to see if there is any incoming messages under this topic using the following command.

./kafka-console-consumer.bat --topic sample --from-beginning --bootstrap-server localhost:9092

Goto: http://localhost:8100/message/[some message] and try to send some message. After that, monitor if the consumer can receive the message.