[herin049]

Description

Omit http.route when the matched Starlette route has no path template instead of using the raw request path. Host-routed spans fall back to the HTTP method as their name.

Per HTTP semantic conventions:

The matched route template for the request. This MUST be low-cardinality and include all static path segments, with dynamic path segments represented with placeholders. [5] http.route: MUST NOT be populated when this is not supported by the HTTP server framework as the route attribute should have low-cardinality and the URI path can NOT substitute it.

Fixes #5275

Type of change

• Bug fix (non-breaking change which fixes an issue)

Validation: 67 tests passed with Starlette 0.13.8 and 67 with 0.46.2; Ruff lint/format and Pylint passed.

Checklist:

• I am a human and not a bot
• I have run tox -e precommit
• I have run tox -e typecheck
• I have run the relevant tests and linting tox environments

[opentelemetry-pr-dashboard]

Pull request dashboard status

Waiting on the author · refreshed 2026-11-01 16:55 UTC

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[Copilot]

🟡 Changes recommended

Host-routed WebSocket connections lose their server span name because their scopes lack a method, requiring a scope-type fallback and a regression test.

1 open issue

• Preserve span names for host-routed WebSocket connections · New

What changed in this PR

This PR addresses #5275 by preventing Starlette instrumentation from using raw request paths as http.route when a matched route has no path template.

Changes:

• Omit unavailable route attributes and use the HTTP method as the fallback span name.
• Add a regression test for host-routed HTTP requests.
• Document the fix in the changelog.

File	Description
instrumentation/​opentelemetry-instrumentation-starlette/​tests/​test_starlette_instrumentation.py	Verify host routing omits http.route and uses GET as the span name.
instrumentation/​opentelemetry-instrumentation-starlette/​src/​opentelemetry/​instrumentation/​starlette/​__init__.py	Remove the raw request path fallback for routes without a template.
.changelog/​5276.fixed	Record the route-attribute fix.

_{Review effort: Balanced}