[Thanatos9404]

Issue number: closes #8577

Summary

Changes

APIGatewayProxyEventV2.path removed len("/" + stage) characters from rawPath for every named stage. Through the execute-api endpoint the stage is part of rawPath, so that worked. Behind a custom domain API mapping, or in SAM local, rawPath has no stage, so the path got cut (/my/path became path for stage dev) and APIGatewayHttpResolver returned 404 for every route.

path now strips the stage only when rawPath is /{stage} or starts with /{stage}/. Otherwise it returns rawPath as is. $default is unchanged.

• rawPath equal to /{stage} (the root of a named stage) now gives / instead of an empty string, so it matches a / route like /{stage}/ already did. The empty string didn't match any route.
• A path that only starts with the stage name, like /devices for stage dev, is no longer cut (it used to become ices).
• LambdaFunctionUrlEvent inherits path, but its stage is always $default, so nothing changes there. APIGatewayProxyEvent (REST), ALBEvent and the VPC Lattice events don't strip a stage in path, so they don't have this bug.

Tests

• tests/functional/event_handler/required_dependencies/test_api_gateway.py: test_api_gateway_v2_stage_prefix_in_raw_path sends a GET through APIGatewayHttpResolver for 7 shapes: named stage with and without the stage in rawPath, $default, rawPath equal to /dev and to /dev/, /devices on stage dev, and /dev/devices. It checks the status code and app.current_event.path.
• tests/unit/data_classes/required_dependencies/test_api_gateway_proxy_event.py: the same shapes against APIGatewayProxyEventV2.path, plus /dev/dev to show the stage is stripped once.

6 of the 14 new cases fail on develop (no stage in rawPath, rawPath equal to the stage, and /devices, in both files). All 14 pass with this change.

Checks

• tests/functional/event_handler, tests/functional/data_classes, tests/unit/event_handler and tests/unit/data_classes: 1385 passed, 1 skipped. Three tests fail on my Windows machine and fail the same way on develop (test_openapi_encode_purepath, test_load_resolver_file_not_found, test_code_pipeline_get_artifact; path separators and temp file locking).
• ruff check and ruff format --check on the changed files: clean.
• mypy and ty check on api_gateway_proxy_event.py: clean.

User experience

Before, with the snippet from the issue (stage dev, custom domain, rawPath /my/path):

print(app.resolve(ev, None)["statusCode"])  # 404
print(app.current_event.path)               # "path"

After: 200, and app.current_event.path == "/my/path". Requests through the execute-api URL (rawPath /dev/my/path) still resolve to /my/path.

This also fixes strip_prefixes for an API mapping path on a named stage. With APIGatewayHttpResolver(strip_prefixes=["/payment"]), stage dev and rawPath /payment/my/path, path used to be ment/my/path, so the prefix never matched and the request got a 404. Now it routes to /my/path.

Risk: code that reads event.path for a named stage behind a custom domain gets the real path instead of a truncated one. If a custom domain request's own path starts with /{stage}/ (a /dev/items route on stage dev), the stage is still stripped, because rawPath alone can't tell the two cases apart. That part behaves as it did before.

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[boring-cyborg]

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[leandrodamascena]

Thanks @Thanatos9404, really appreciate this one! I ran the suites and also deployed it behind a real HTTP API with $default, dev and stage-1 stages, plus direct invokes with the custom-domain event shape. Everything that worked before still works, and the cases that change were all returning garbage before. I even found one more on develop: stage dev with rawPath /api/users was routed to /users by accident because the stage length matched the segment. Your fix handles it.

I'm approving now, but this will go out in 3.38.0, so it will sit here for a bit before I merge. You don't need to rebase or touch anything in the meantime, I'll take care of that, and you'll get the credit in the release notes. Thank you so much!

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.94%. Comparing base (6c841da) to head (d875c05).
⚠️ Report is 1 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #8605   +/-   ##
========================================
  Coverage    96.93%   96.94%           
========================================
  Files          318      318           
  Lines        16045    16051    +6     
  Branches      1425     1427    +2     
========================================
+ Hits         15554    15560    +6     
  Misses         349      349           
  Partials       142      142           

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[boring-cyborg]

Awesome work, congrats on your first merged pull request and thank you for helping improve everyone's experience!

[powertools-for-aws-oss-automation]

Awesome work, congrats on your first merged pull request and thank you for helping improve everyone's experience!