When do aggregators remove or delete processed messages or events from a queue or storage?

Aggregators remove or delete processed messages or events from the queue or storage after successful confirmation of their processing. This usually occurs when the message handler has completed all necessary actions without errors, and the system has received confirmation that the message was processed correctly.

For example, in message queue systems (RabbitMQ, Kafka), the consumer sends an acknowledgment (ack) after processing, and only then is the message removed from the queue to prevent reprocessing. If acknowledgment is not received, the message may remain in the queue for a retry.

Thus, deletion occurs:

• after successful processing;
• after receiving confirmation from the handler;
• to prevent reprocessing and free resources.