Consumer Group

What is a consumer group?

A consumer group is a group of consumers, usually multiple clients grouped with the same characteristics and/or replicas/workers of the same application/client.

The added layer of a consumer group enables ordering control and avoids duplicate processing of messages within the same type of consumer(s).

Each message will be delivered in parallel to all consumer groups.

Each consumer group gets the same messages

Inside the consumer group, a message will be delivered to only one consumer

There is no consumer without a consumer group.

FAQ

Q: "How can I ensure that only one consumer processes a message?"

A: At Memphis.dev, our consumption pattern ensures that all connected consumer groups simultaneously receive each message. Within each consumer group, only a single consumer processes a message. This approach guarantees that, for use cases requiring exactly-once processing, a single consumer group is the way to go. To further enhance this, consider implementing ack-based retention.