[APM] Bug: Error count threshold alert allows for defining 0 error as threshold, but doesn't show the value

[formgeist]

Kibana version

7.15 BC

APM Server version (if applicable)

No response

Elasticsearch version (if applicable)

No response

Steps to Reproduce

1. Go to create a new rule for an Error count threshold for any service or any environment
2. Change the error count threshold to 0 which is valid, but the expression doesn't show the value selected

Expected Behavior

I'd expect the value to be shown in the expression 0 errors

Actual Behavior

There's no value shown in the expression which can make it difficult to understand whether the input is valid.

[elasticmachine]

Pinging @elastic/apm-ui (Team:apm)

[sorenlouv]

Related #108496

[elasticmachine]

Pinging @elastic/kibana-alerting-services (Team:Alerting Services)

[sorenlouv]

@elastic/kibana-alerting-services Does this belong to you, the elastic-charts team or the apm team?

[afgomez]

@sqren We had a similar error in logs, which was caused by treating the relevant value as falsy when checking for its presence instead of explicitly comparing it with undefined. Maybe something similar happens in APM.

For inspiration, the fix in logs lives in #111150

[sorenlouv]

@afgomez Thanks! So it sounds like this is a problem in APM and not stack alerting. I'll update the labels then

[botelastic]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[formgeist]

This is still an issue since 8.2.0

[kpatticha]

This should be fixed here: #136919

Please feel free to reopen if you think it hasn't be solved