[processor/k8sattributes] Allow specifying that all labels/annotations should be copied

[TylerHelmuth]

Component(s)

processor/k8sattributes

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

Today the processor allows configuring which specific labels and annotations should be added as resource attributes. For users who want all the labels and/or annotations, this requires them to:

1. Know all the possible keys
2. List all the possible keys in the configuration

In my opinion this is a poor user experience.

Describe the solution you'd like

As a quality of life improvement I'd like to be able to specify the "Add all the labels from the pod" or "Add all the annotations from the namespace" and so on. I think the configuration API would look something like:

k8sattributes/:
 extract:
   allAnnotationsFrom:
     - pod
     - namespace
   allLabelsFrom:
     - pod 

I also don't believe this needs to be mutually exclusive from annotations and labels configuration option. Users should be allowed to use allAnnotationsFrom and annotations so that they can specify regexp extractions to get even more attributes. I does sound like a good idea to validate that if both options are used (allAnnotationsFrom and annotations or allLabelsFrom and labels) that each extraction in annotations/labels uses regexp.

[github-actions]

Pinging code owners:

• processor/k8sattributes: @dmitryax @rmfitzpatrick @fatsheep9146

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

[TylerHelmuth]

I started work on this an then realized the current extraction logic already allows grabbing all the labels and annotations:

extract:
  labels:
    - tag_name: $$1
      key_regex: (.*)
      from: pod
    - tag_name: $$1
      key_regex: (.*)
      from: namespace
  annotations:
    - tag_name: $$1
      key_regex: (.*)
      from: pod
    - tag_name: $$1
      key_regex: (.*)
      from: namespace

It is a little more difficult than the config I proposed, but is a useable solution. Based on the ongoing filtering config work (#25128, #25135) I think we hold on this proposal for now.

[dmitryax]

@TylerHelmuth this can be closed right?