Enqueue acknowledgements with EasyNetQ

Question

I want to receive async acknowledgements that a message has, in fact, been placed in a queue. I've searched quite a bit, and tried various ways of using EasyNetQ's PublishAsync for confirmations, but can't seem to find the Bus connection configuration and code combination that will give me such an acknowledgement.

Perhaps PublishAsync is not the way to go for this, and I've overlooked something else in the EasyNetQ API? Anyone else have experience with implementing this scenario with EasyNetQ?

score 1 · Accepted Answer · answered Oct 30 '14 at 20:44

1

For that kind of guarantee you need to turn on publisher confirms. See the documentation:

https://github.com/mikehadlow/EasyNetQ/wiki/Publisher-Confirms

answered Oct 30 '14 at 20:44

Mike Hadlow

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1

Publish Confirms wouldn't be enough -- the confirm only an acknowledgement from the broker. You need to set `mandatory` to `true` when performing the publish. – pardahlman Oct 20 '16 at 06:16
The link needs updating to https://github.com/EasyNetQ/EasyNetQ/wiki/Publisher-Confirms – Boggin Aug 14 '17 at 10:35

score 1 · Answer 2 · answered Oct 20 '16 at 06:33

The official documentation on Publish Confirm states that

For unroutable messages, the broker will issue a confirm once the exchange verifies a message won't route to any queue (returns an empty list of queues)

This means that you will get a Publish Confirm, even though there is no queues bound to the exchange with matching routing key. If you want to make sure that the message is published to at least one queue, you need to make sure that the mandatory flag is set to true in the BasicPublish

channel.BasicPublish(
    exchange: "my_exchange",
    routingKey:"routingkey",
    mandatory: true, // at least one queue
    basicProperties: null,
    body: new byte[0]
);

The default value when mandatory is not provided is false. So Mike Hadlow's answer is not 100% accurate. There is an open issue for RawRabbit regarding this, that is due in the next release.

Enqueue acknowledgements with EasyNetQ

2 Answers2