[processor/metricstransform] support value regex matching pattern when renaming label values

[karmingc]

Component(s)

processor/metricstransform

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

Currently, the metricstranform processor support renaming label values such as the following:

# from https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/processor/metricstransformprocessor#rename-label-values
# rename the label value slab_reclaimable to sreclaimable, slab_unreclaimable to sunreclaimable
include: system.memory.usage
action: update
operations:
  - action: update_label
    label: state
    value_actions:
      - value: slab_reclaimable
        new_value: sreclaimable
      - value: slab_unreclaimable
        new_value: sunreclaimable

However, there might be situations where we want to use a regex matching pattern instead of a strict one. For example, when dealing with http.status_code, the range goes from 1xx to 5xx so adding these values 1 by 1 is long and can be error-prone.

The goal is to reduce cardinality such as 200, 201, 202... to 2xx to reduce cardinality.

Describe the solution you'd like

Potentially add a value_match_type field under the operations field. But open to suggestion.

Describe alternatives you've considered

We can leverage the transform processor such as:

  transform/metric:
    error_mode: ignore
    metric_statements:
      - context: datapoint
        statements:
          - replace_pattern(attributes["http.status_code"], "\\b1\\d{2}\\b", "1xx")
          - replace_pattern(attributes["http.status_code"], "\\b2\\d{2}\\b", "2xx")
          - replace_pattern(attributes["http.status_code"], "\\b3\\d{2}\\b", "3xx")
          - replace_pattern(attributes["http.status_code"], "\\b4\\d{2}\\b", "4xx")
          - replace_pattern(attributes["http.status_code"], "\\b5\\d{2}\\b", "5xx")

Additional context

No response

[github-actions]

Pinging code owners:

• processor/metricstransform: @dmitryax

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[github-actions]

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Pinging code owners:

• processor/metricstransform: @dmitryax
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[crobert-1]

I believe this is a duplicate of #24366, but please let me know if I've misunderstood