What does the consumer do after receiving a message from RabbitMQ? What happens to the message after processing?

After receiving a message, a RabbitMQ consumer typically performs the following actions:

1. Processes the message — executes business logic, such as saving data to a database, calling external services, etc.
2. Acknowledges receipt of the message to the RabbitMQ server if processing was successful.

What happens to the message after processing:

• If the consumer sends an acknowledgment (ack), RabbitMQ removes the message from the queue, considering it processed.
• If the consumer does not acknowledge the message (for example, in case of an error), the message may be re-sent to another consumer or placed in a dead-letter queue, depending on the configuration.

Example in Python using pika:

channel.basic_consume(queue='task_queue', on_message_callback=callback, auto_ack=False)

def callback(ch, method, properties, body):
    # process the message
    process(body)
    # acknowledge
    ch.basic_ack(delivery_tag=method.delivery_tag)