[herin049]

Description

Implements the OTel metrics Bind API.

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-api

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

[Copilot]

Pull request overview

This PR adds support for “bound” synchronous metric instruments (per the OTel Metrics Bind concept), allowing instruments to be pre-associated with a set of attributes and to merge those attributes with per-call attributes at recording time.

Changes:

• Adds _bind() to synchronous instrument types and introduces bound-instrument wrappers that delegate recording while merging/deepcopying attributes.
• Adds API-level tests covering delegation behavior, attribute merging semantics, deepcopy behavior, rebinding flattening, and proxy instrument interaction.
• Adds SDK-level tests validating that bound recordings flow through the measurement consumer and preserve existing validation behavior.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 4 comments.

File	Description
opentelemetry-api/src/opentelemetry/metrics/_internal/instrument.py	Adds _bind() and bound instrument wrapper implementations for synchronous instruments.
opentelemetry-api/tests/metrics/test_instruments.py	Adds API tests for bound instrument semantics (merge/deepcopy/rebind/proxy).
opentelemetry-sdk/tests/metrics/test_instrument.py	Adds SDK tests to ensure bound instruments propagate measurements/validation correctly.

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[github-actions]

This PR has been automatically marked as stale because it has not had any activity for 14 days. It will be closed if no further activity occurs within 14 days of this comment.
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[opentelemetry-pr-dashboard]

Pull request dashboard status

Waiting on the author · refreshed 2026-10-26 20:54 UTC

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[github-actions]

This PR has been automatically marked as stale because it has not had any activity for 14 days. It will be closed if no further activity occurs within 14 days of this comment.
If you're still working on this, please add a comment or push new commits.

[opentelemetry-pr-dashboard]

Hi @herin049 — just a friendly reminder that this pull request is waiting on you. The dashboard status comment has the open items and is kept current.

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