opentelemetry-exporter-prometheus: add support to configure Resource attributes as metric labels

[herin049]

Description

Adds support for adding Resource attributes as metric labels for the Prometheus exporter in accordance to the Prometheus spec.

Fixes #5110

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

uv run tox -e py314-test-opentelemetry-exporter-prometheus

Does This PR Require a Contrib Repo Change?

• Yes. - Link to PR:
• No.

Checklist:

• Followed the style guidelines of this project
• Changelogs have been updated
• Unit tests have been added
• Documentation has been updated

[MikeGoldsmith]

🎉

[github-actions]

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[Copilot]

Pull request overview

This PR adds a configuration hook to the Prometheus exporter that allows selected OpenTelemetry Resource attributes to be copied onto exported Prometheus metrics as labels, aligning the Python Prometheus exporter with the Prometheus compatibility guidance in the OpenTelemetry specification.

Changes:

• Introduces a resource_attr_filter callback on PrometheusMetricReader to select which Resource attributes should become metric labels (sanitized to valid Prometheus label names).
• Updates label construction so copied Resource labels are included on exported samples, while preserving precedence (metric point attributes override copied Resource attributes).
• Adds unit tests and documentation describing the new configuration, plus a changelog entry.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
exporter/opentelemetry-exporter-prometheus/src/opentelemetry/exporter/prometheus/init.py	Adds resource_attr_filter wiring and includes filtered Resource attributes in label generation.
exporter/opentelemetry-exporter-prometheus/tests/test_prometheus_exporter.py	Adds tests covering default behavior, filtering, sanitization, and precedence with point/scope labels.
docs/exporter/prometheus/prometheus.rst	Documents how to enable Resource attributes as metric labels via resource_attr_filter.
.changelog/5122.added	Records the new Prometheus exporter feature in the changelog.

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Pull request dashboard status

Merged · refreshed 2026-08-17 08:17 UTC

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