What ensures the absence of conflicts between consumer groups when processing a single message in a message consumption system?

The absence of conflicts between consumer groups when processing a single message in messaging systems (e.g., Kafka) is ensured by the concept of consumer groups. Each message from a topic is delivered to only one consumer within a group, and different groups can independently read the same messages.

Thus, if you have multiple consumer groups, they do not conflict because each group receives its own copy of the message. Within a group, messages are distributed among consumers, which prevents duplicate processing.

Example: in Apache Kafka, if you have a topic with multiple partitions and two consumer groups, each group will receive all messages, but within the group, each message will be processed by only one consumer.