Does RabbitMQ (called from a c# client) have the ability to distribute work on a queue and allow the publisher to receive confirmations that that work processed successfully?
It seems like it should be possible without adding an extra queue, but unless I'm missing something acknowledgements/confirms don't tell the original publisher that a message was dealt with successfully. So it has no way of knowing if all of its work was handled.
I'm currently using the standard rabbit c# client, but I know easynetq is also very mature so suggestions for a good way to achieve this with either would be appreciated.
No, absolutely nothing in RabbitMQ will do that. The most you get out of RabbitMQ is an acknowledgment that the message was delivered to a worker, which you may interpret as "someone started work on the task". Your workers will need to find a way to communicate back to the caller with the results of the task, which could well be another exchange-queue mechanism but it is more likely that your workers will put the results of the task in Redis or database and if properly written, even a way to communicate failure codes via the same.