This article will teach you how to create a Spring Cloud Stream app that works with a messaging service (like Apache Kafka, RabbitMQ, etc.), You’ll be using functional, reactive code—leveraging Spring’s WebFlux—and Spring Cloud Stream’s functional building model,
Today, you are going to make an app that has a publisher, a processor, and a consumer. It will leverage two topics to publish a stream of integers, process the integers to calculate a running total, and consume the processed data. In the beginning, these messages will be simple (strings/integers)—but later you’ll see how Spring Cloud Stream makes mapping POJOs (Plain Old Java Objects) to messages using JSON mapping simple!