Scaling out with Kafka Streams

To scale out the architecture as promised, we must follow these steps:

1. Run a console consumer for the uptimes topic, shown as follows:

$ ./bin/kafka-console-consumer --bootstrap-server localhost:9092 
--topic uptimes --property print.key=true

2. Run the application jar from the command line, shown in the following code:

$ java -cp ./build/libs/kioto-0.1.0.jar 
kioto.plain.PlainStreamsProcessor

This is when we verify that our application really scales out.

3. From a new command-line window, we execute the same command, shown as follows:

$ java -cp ./build/libs/kioto-0.1.0.jar 
kioto.plain.PlainStreamsProcessor

The output should be something like the following:

2017/07/05 15:03:18.045 INFO ... Setting newly assigned 
partitions [healthchecks-2, healthchecks -3]

If we remember the theory of Chapter 1, Configuring Kafka, when we created our topic, we specified...