Understanding consumer-timeout behaviour

[Gary]

Using RabbitMQ v3.13.7 in a Docker container I am trying to understand how queues configured with a consumer-timeout behave if a message is NOT acknowledged within the timeout. From the docs, "if a consumer does not ack its delivery within the timeout value its channel is closed ... with a channel exception".

Using either a classic or quorum durable queue, configured with x-consumer-timeout set during creation via the management console (and confirmed via the management console it is configured so), I ran a simple Spring Boot rabbit listener configured to MANUALLY acknowledge messages. What I found was that the message remained unacknowledged beyond the queue consumer-timeout value as shown in the management console, no exception was thrown and the message was not automatically dead-lettered/discarded/re-queued. I repeated the same test with a Python application also  configured to manually acknowledge messages. The result was the same. I could only get the message to be re-queued if I stopped either application.

The Spring application:

@SpringBootApplication
public class RabbitMQMinimalApplication {
    static void main(String[] args) {
        SpringApplication.run(RabbitMQMinimalApplication.class, args);
    }

    @RabbitListener(queues = "incomingQueue")
    public void listen(String in)  {
        log.info(in);
    }
}

Its configuration:

spring.rabbitmq.listener.simple.acknowledge-mode=manual
spring.rabbitmq.listener.direct.acknowledge-mode=manual

The python application:

import pika

def callback(ch, method, properties, body):
    print(f" [x] Received {body}")

if __name__ == '__main__':
    connection = pika.BlockingConnection(pika.ConnectionParameters('localhost'))
    channel = connection.channel()
    channel.basic_consume(queue='incomingQueue', on_message_callback=callback, auto_ack=False)
    print(' [*] Waiting for messages. To exit press CTRL+C')
    channel.start_consuming()

It appears that consumer-timeouts are not working as per the documentation. Could anyone confirm this?

Thanks

Gary