In this article, we’ll introduce the main concepts and constructs of Spring Cloud Stream with some simple test-examples based on EmbeddedKafkaRule using MessageCollector

Now let’s see the main concepts:

Bindings: a collection of interfaces that identify the input and output channels declaratively

Binder: messaging middleware implementation such as Kafka or another

Channel: represents the communication pipe between messaging middleware and the application

StreamListeners: message-handling methods in beans that will be automatically invoked on a message from the channel after the MessageConverter does the serialization or deserialization between middleware specific events and domain object types or “POJO”

Message Schemas: used for serialization and deserialization of messages, these schemas can be statically read from a location or loaded dynamically

We will need at least one producer and a consumer to test the message and send and receive operations. Below is the sample code for a producer and consumer in its simplest form, developed using Spring Cloud Stream.

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