OTTL: Allow copying attributes with a regex

[gouthamve]

Component(s)

pkg/ottl, processor/transform

Is your feature request related to a problem? Please describe.

A common usecase in Prometheus is to copy all resource attributes matching a prefix / regex into metric attributes.

Right now its not possible and users are asking for workaround features in the exporter itself: #22914

The usecase in the above issue is that they'd like to copy all the resource attributes withk8s.* regex into metric attributes. And right now they're doing the following:

transform:
  metric_statements:
    - context: datapoint
      statements:
        - set(attributes["k8s_replicaset_name"], resource.attributes["k8s.replicaset.name"])
        - set(attributes["k8s_deployment_name"], resource.attributes["k8s.deployment.name"])
        - set(attributes["k8s_statefulset_name"], resource.attributes["k8s.statefulset.name"])
        - set(attributes["k8s_hpa_name"], resource.attributes["k8s.hpa.name"])
        - set(attributes["k8s_volume_name"], resource.attributes["k8s.volume.name"])
        - set(attributes["k8s_job_name"], resource.attributes["k8s.job.name"])
        ....

This is not scalable as new attributes that are added will be missed.

Describe the solution you'd like

Something like: copy_keys(target, source, regex)

transform:
  metric_statements:
    - context: datapoint
      statements:
        - copy_keys(attributes, resource.attributes, "k8s.*")

Describe alternatives you've considered

No response

Additional context

No response

[github-actions]

Pinging code owners:

• pkg/ottl: @TylerHelmuth @kentquirk @bogdandrutu @evan-bradley
• processor/transform: @TylerHelmuth @kentquirk @bogdandrutu @evan-bradley

See Adding Labels via Comments if you do not have permissions to add labels yourself.

[TylerHelmuth]

We have had similar requests before (#14946) and it continues to be a valuable function to add. @gouthamve is this something you want to work on?

[TylerHelmuth]

I wonder if merge_maps can be used somehow.

[jmichalek132]

I wonder if merge_maps can be used somehow.

Hi, I wrote the referenced issue, that wouldn't work on our use case, since we want to keep the full set of resource attributes on target_info metrics and copy over their subset on the actual metric itself. To be able to use merge_maps we would need to remove items from resource attributes which would remove them from the target_info metric.

[github-actions]

This issue has been inactive for 60 days. It will be closed in 60 days if there is no activity. To ping code owners by adding a component label, see Adding Labels via Comments, or if you are unsure of which component this issue relates to, please ping @open-telemetry/collector-contrib-triagers. If this issue is still relevant, please ping the code owners or leave a comment explaining why it is still relevant. Otherwise, please close it.

Pinging code owners:

• processor/transform: @TylerHelmuth @kentquirk @bogdandrutu @evan-bradley
• pkg/ottl: @TylerHelmuth @kentquirk @bogdandrutu @evan-bradley

See Adding Labels via Comments if you do not have permissions to add labels yourself.

[github-actions]

This issue has been inactive for 60 days. It will be closed in 60 days if there is no activity. To ping code owners by adding a component label, see Adding Labels via Comments, or if you are unsure of which component this issue relates to, please ping @open-telemetry/collector-contrib-triagers. If this issue is still relevant, please ping the code owners or leave a comment explaining why it is still relevant. Otherwise, please close it.

Pinging code owners:

• processor/transform: @TylerHelmuth @kentquirk @bogdandrutu @evan-bradley
• pkg/ottl: @TylerHelmuth @kentquirk @bogdandrutu @evan-bradley

See Adding Labels via Comments if you do not have permissions to add labels yourself.

[github-actions]

This issue has been closed as inactive because it has been stale for 120 days with no activity.