search

arobson / rabbot

Deprecated: Please see https://github.com/Foo-Foo-MQ/foo-foo-mq
MIT License
276 stars 129 forks source link

Unacked messages when working with reply and more option #192

Open ptusch opened 5 years ago

ptusch commented 5 years ago

When you work with the rpc feature of rabbot, you may be tempted to use the intermediate callback and more option. If you do that (or plan to do that) be prepared to have a bunch of unacked messages in your queue. There seems to be some weirdness that invalidates previously performed acks. It's a bit hard to explain, please have a look at the attached examples.

A workaround would be to use the noAck: true option upon consuming things. Of course, this may break your workflow so be vary.

ptusch commented 5 years ago

rabbot_sample.tar.gz

ptusch commented 5 years ago

I've pinpointed the issue down to the ackBatch processing. Since my usecase uses the batchAacking, I have an interval that fires each 500ms.

So imagine using msg.reply before and the next msg.reply after the batch processing, you end up in invalid states. The messages count is down to 0 and further acks will not be performed, resulting in unacked messages.

A better workaround (though, requires code change) is to remove the raw.ack() call and call msg.ack() in your business logic.

ptusch commented 5 years ago

I wad able to fix the issue. It's a bit disgusting but what can I say. It's working. Please have a look if you feel like it: https://github.com/hufsm/rabbot/pull/21/files#diff-25b7d53c91b664dd589db8a4e4e02119