feat(flask): Add http.route attribute

[alexander-alderman-webb]

Description

Set the http.route attribute on the server span in patches for Flask endpoints.

Issues

Reminders

• Please add tests to validate your changes, and lint your code using uv run ruff.
• Add GH Issue ID & Linear ID (if applicable)
• PR title should use conventional commit style (feat:, fix:, ref:, meta:)
• For external contributors: CONTRIBUTING.md, Sentry SDK development docs, Discord community

[sentry-warden]

http.route access crashes when request.url_rule is None

In _request_started, request.url_rule.rule is used without a null check; unmatched routes leave url_rule as None and will raise AttributeError under span streaming. Guard like FastAPI (route_path is not None) or wrap with capture_internal_exceptions, matching _set_transaction_name_and_source.

Evidence

• Hunk adds SPANDATA import used by the new http.route write in _request_started.
• That path does server_span.set_attribute(SPANDATA.HTTP_ROUTE, request.url_rule.rule) with only a server_span is not None guard.
• Nearby _set_transaction_name_and_source already try/excepts the same request.url_rule access because it can be missing.
• FastAPI only sets HTTP_ROUTE when route_path is not None; Flask does not.
• test_http_route only covers a matched /message/123456 path, not 404/unmatched routing.

Also found at 2 additional locations

• sentry_sdk/integrations/flask.py:154-156
• tests/integrations/flask/test_flask.py:162-162

_{Identified by Warden · code-review, find-bugs · FE7-QHG}

[github-actions]

Codecov Results 📊

✅ 130423 passed | ❌ 1 failed | ⏭️ 7110 skipped | Total: 137534 | Pass Rate: 94.83% | Execution Time: 471m 33s

📊 Comparison with Base Branch

Metric	Change
Total Tests	📈 +32133
Passed Tests	📈 +31501
Failed Tests	📈 +1
Skipped Tests	📈 +631

➕ New Tests (1)

View new tests

• test_continuous_profiler_auto_start_and_stop_sampled_span_streaming[experiment-thread]
  • File: tests.profiler.test_continuous_profiler
  • Status: ❌ Failing

❌ Failed Tests

test_continuous_profiler_auto_start_and_stop_sampled_span_streaming[experiment-thread]

File: tests.profiler.test_continuous_profiler
Suite: py3.15-common
Error: AssertionError: profiler should not be running assert 'ec68987471e1484dadf859f0946ed39a' is None + where 'ec68987471e1484dadf859f0946ed39a' = get_profiler_id()

Stack Trace

tests/profiler/test_continuous_profiler.py:896: in test_continuous_profiler_auto_start_and_stop_sampled_span_streaming
    assert get_profiler_id() is None, "profiler should not be running"
E   AssertionError: profiler should not be running
E   assert 'ec68987471e1484dadf859f0946ed39a' is None
E    +  where 'ec68987471e1484dadf859f0946ed39a' = get_profiler_id()

✅ Patch coverage is 100.00%. Project has 2498 uncovered lines.
✅ Project coverage is 90.27%. Comparing base (base) to head (head).

Coverage diff

@@            Coverage Diff             @@
##          main       #PR       +/-##
==========================================
+ Coverage    90.27%    90.27%        —%
==========================================
  Files          193       193         —
  Lines        25682     25686        +4
  Branches      9468      9470        +2
==========================================
+ Hits         23184     23188        +4
- Misses        2498      2498         —
- Partials      1442      1442         —

---

Generated by Codecov Action