opentelemetry-util-http: don't raise on unparsable request targets

[henry3260]

Description

_parse_url_query in opentelemetry-util-http called urlparse on request targets that come
straight off the request line. urlparse raises ValueError ("Invalid IPv6 URL") on targets such
as //exa[mple, and because the exception propagated out of instrumentation, tornado turned those
requests into 500s. It now returns empty components instead.

The components are deliberately not recovered by splitting on ?: url.query is optional under the
semantic conventions, and every current caller sources url.path from the framework
(request.path in tornado, the route template in asgi), so nothing downstream regresses. Preserving
the query for unparsable targets would be a separate change.

Related to #4447, which was closed by #4551 by avoiding _parse_url_query in the WSGI
instrumentation; the same root cause remained in the shared helper for the other callers.

Fixes # (issue)

Type of change

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

How Has This Been Tested?

• New util/opentelemetry-util-http/tests/test_parse_url_query.py covers absolute urls,
  request-target-only urls, no query, empty url, and unparsable urls.
• New tornado regression test test_invalid_request_uri_does_not_break_request asserts that
  //exa[mple still answers 404 with http.target and http.status_code set. Reverting the
  helper makes it fail with 500 != 404.
• uv run tox -e py313-test-util-http — 66 passed.
• uv run tox -e py313-test-instrumentation-tornado — 46 passed. test_remove_sensitive_params
  fails locally because http_server_mock cannot bind port 5000; it fails the same way without
  this change.
• uv run pre-commit run ruff --all-files and ruff-format pass.

Does This PR Require a Core Repo Change?

• Yes. - Link to PR:
• No.

Checklist:

See contributing.md for styleguide, changelog guidelines, and more.

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

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Pull request dashboard status

Waiting on maintainers · refreshed 2026-08-21 01:51 UTC

Merge when ready.

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