fix(event_handler): fix forward references resolution in OpenAPI

[xdxindustries]

Issue number: #5884

Summary

Changes

Fix type resolution for forward references in Annotated type hints to correctly handle body parameters in API Gateway handlers. Currently, when using quoted type annotations with Annotated and Body, parameters are incorrectly treated as query parameters instead of body parameters due to improper globals resolution in get_typed_signature().

The fix updates the globals retrieval logic to properly resolve forward references in type annotations.

User experience

Before:

@app.post("/users")
def create_user(
    user_create_request: 'Annotated[UserCreate, Body()]',
) -> dict:
    return {"message": "success"}

Results in a 422 error treating user_create_request as a missing query parameter, even when the JSON body is correctly provided.

After:

# Same code works as expected

Correctly identifies the parameter as a body parameter and properly validates the incoming JSON request body.

Checklist

• Meet tenets criteria
• I have performed a self-review of this change
• Changes have been tested
• Changes are documented
• PR title follows conventional commit semantics

Is this a breaking change?

No, this is a bug fix that restores expected functionality for forward references in type annotations.

Acknowledgment

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Disclaimer: We value your time and bandwidth. As such, any pull requests created on non-triaged issues might not be successful.

[boring-cyborg]

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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

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.17%. Comparing base (4a8d4e8) to head (ddb46b5).
Report is 2 commits behind head on develop.

Additional details and impacted files

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  Coverage    96.17%   96.17%           
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  Files          232      232           
  Lines        10941    10941           
  Branches      2023     2023           
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  Hits         10522    10522           
  Misses         329      329           
  Partials        90       90           

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[leandrodamascena]

Hi @xdxindustries! Thank you SO MUCH for fixing this! This also paves the way to solve this other bug: #5098.

I'll send some PRs to resolve this other bug definitively and add more tests. I hope to make a release today or tomorrow and will ping you to test.

[leandrodamascena]

Approved!!!

[boring-cyborg]

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

[xdxindustries]

@leandrodamascena as you work on the other issues I will say there was one thing that took a lot of debugging when working on complicated types/this issue. that might help your fix/debugging other bugs, you really want the @app decorator directly next to your function, opposite of docs examples. Otherwise types were not getting resolved correctly even when getting the globals, as it ends up getting the globals of the wrapper:

@app.post(...)
@tracer.capture_method
def function_with_forwardTypes(some_var: "Annotated[ ....etc"

^--- This fails as when resolving the globals it gets the globals of the tracer capture function instead of the target function
/---- this works
@tracer.capture_method
@app.post(...)
def function_with_forwardTypes(some_var: "Annotated[ ....etc"