Negative acknowledgment not working anymore when value is set to 0

[Chr3is]

Version: 2.8.4

Describe the bug

With following commit: a1a5d48#diff-49bc63455f16e2f0b1fe17ed1ec885135d494883d5a21a3da53d031098d09a33R2485
the behavior how the nack in the listener container is handled was changed. Allowed values for nack are >=0. However when setting the value to 0 you will end in an endless partition reseeking because the new introduced method pauseForNackSleep checks the nack value against > 0 and NOT against >= 0. Due to this behavior the nack value is never reset to -1.

To Reproduce
execute acknowledgment.nack(0);

Expected behavior
When setting the value to 0 an endless partition reseeking does not happen.

[sta-szek]

Hi @garyrussell , @artembilan
how can i check if i am affected? i also do nack(0) - for the very first event and i faced some infinitive loop issue.
we use:

% mvn dependency:tree | grep spring-kafka                                                   
[INFO] |  +- org.springframework.kafka:spring-kafka:jar:2.8.4:compile

is the issue solved / backported to 2.8.4 already?

--- edit
just check sources for 2.8.4 and looks like we are still affected -> i see old code. since which version it is fixed?
and next quesiton ,not sure if you can answer, would be when it will be in spring-boot?
and :) when the issue was introduced? i would like to switch back to "working" version to confirm my issue is exactly this, otherwise i continue investigations

[Chr3is]

@sta-szek this bug was introduced with be4b1bf which was part of the v2.8.4 release (https://github.com/spring-projects/spring-kafka/releases/tag/v2.8.4) - the last working version should be 2.8.3 therefore. You can also "fix this" problem in 2.8.4 by setting the nack value from 0 to 1.

[artembilan]

This is going to be released as a fix in the next 2.8.5 on April 18th: https://calendar.spring.io/

[sta-szek]

@sta-szek this bug was introduced with be4b1bf which was part of the v2.8.4 release (v2.8.4 (release)) - the last working version should be 2.8.3 therefore. You can also "fix this" problem in 2.8.4 by setting the nack value from 0 to 1.

hi, thanks! indeed.
i switched back to spring-kafka 2.8.3 and the issue gone

however, if i add some events to topic, to avoid nack(0) then in my case the issue still happens in 2.8.4, but its, how to say it, less invasive.

i mean, if i nack(0) then after 1h i have ~200k events repeated.
if i put any event and do nack(x) where x > 0, then i got ~15k events repeated after 1h.

i would be happy to test spring-kafka 2.8.5-SNAPSHOT before release, to make sure the problem is solved fully, how can i do it?

[tomazfernandes]

You can use Spring SNAPSHOT versions by adding the snapshot repositories:

repositories {
    maven {
        url 'https://repo.spring.io/snapshot'
    }
}

dependencies {
    implementation 'org.springframework.kafka:spring-kafka:2.8.5-SNAPSHOT'
}