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How to customize API validation error response in Flask

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#564 2 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
25/100
Issue type
Feature
Clarity
Needs clarification
Activity status
Stale
Tech stack
flask, python
Domain
api, backend

Research direction

Start with the Flask integration instructions linked in the issue and trace how incoming validation errors are turned into the generic response. Determine how an application could customize the response while accessing the status code, validation message, and title; done should include documented, working behavior for custom responses.

Written by the indexing model from the issue text.

Description

area/documentation kind/bug kind/missing-implementation
Actual Behavior

Getting generic resposne on validation error

{
    "errors": [
        {
            "class": "<class 'openapi_core.validation.schemas.exceptions.InvalidSchemaValue'>",
            "status": 400,
            "title": "Value {'flag': 'testF'} not valid for schema of type object: (<ValidationError: \"'testF' is too short\">,)"
        }
    ]
}
Expected Behavior

We should be able to generate custom responses, and should be able to capture the validation error info e.g. status code, validation error message, and title

Steps to Reproduce

I set up a flask server and followed the instructions provided here

Currently openapi-core is validating the incoming requets properly, however the response generated is as follows

{
    "errors": [
        {
            "class": "<class 'openapi_core.validation.schemas.exceptions.InvalidSchemaValue'>",
            "status": 400,
            "title": "Value {'flag': 'testF'} not valid for schema of type object: (<ValidationError: \"'testF' is too short\">,)"
        }
    ]
}

I want to customize the response body as per my application,

I wanted to know if is there any provision using which we can provide custom responses.

or even if we somehow capture the validation error info e.g. status code, validation error message, and title then we can generate our own response with the available information.

Thanks in advance

OpenAPI Core Version

0.17.1

OpenAPI Core Integration

Flask

Affected Area(s)

No response

References

No response

Anything else we need to know?

No response

Would you like to implement a fix?

None

Dominant language
Python
Stars
368
Forks
140
PR merge metrics
No merged PRs in 30d

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