Kafka vs RabbitMQ — differences. How do consumer groups work in Kafka?

Differences between Kafka and RabbitMQ:

• Kafka is a distributed streaming platform with high throughput and fault tolerance, focused on processing large volumes of data and storing messages in topics with the ability for re-reading.
• RabbitMQ is a message broker supporting various protocols (AMQP), focused on complex routing, guaranteed delivery, and flexibility in integration.

Consumer groups in Kafka:

A consumer group is a group of consumers that jointly read data from a topic. Each partition of a topic can only be read by one consumer from the group, ensuring parallelism and scalability.

Working principle:

• The topic is divided into partitions.
• Each partition is assigned to one consumer from the group.
• If there are fewer consumers than partitions, some consumers read multiple partitions.
• If there are more consumers than partitions, some consumers remain idle.

This allows load distribution and balancing when the number of consumers changes.