Ack only successful messages and expose ways to control nacks for users that want them #10
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This will allow them to actually be used.
The existing behaviour is basically the same as always having no_ack=TRUE, in that messages are unequivocally acknowledged. However, it is sometimes desirable to distinguish processing which fails from that which succeeds, so callbacks which throw an error will now nack messages instead -- without requeing them. Since nack without requeue is only *semantically* (not operationally) different than acknowledgment, existing workflows are unlikely to be affected. Documentation has been updated to reflect this behaviour. Part of #2.
This gives users complete control over nacks.
Closed
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Follows discussion in #2.
Changes:
Consumers created with
amqp_consume()will now acknowledge messages only after the callback has run. Moreover, when a callback fails the message in question will be nacked instead. The newrequeue_on_errorparameter controls whether messages should be redelivered when callbacks error; by default it isFALSE, in line with current behaviour.For complete control over when and how messages are nacked, one can use the new
amqp_nack()function, which works likestop()inside a message handler. This allows for complex acknowledgement behaviour for a consumer, which might e.g. be used in combination with a dead letter exchange.Includes tests and documentation updates.