[QUESTION] How can I validate request body as is?

Description

How can I validate request body as is?

Additional context

I try to use fastapi. First I wrote simple api, as shown below.

from fastapi import FastAPI, Body


app = FastAPI()


@app.post("/test")
def test(i: int = Body(..., embed=True),
         f: float = Body(..., embed=True),
         s: str = Body(..., embed=True),
         b: bool = Body(..., embed=True)):
    return {'int': i, 'float': f, 'str': s, 'bool': b}

And request with valid body shown below. I think this result is correct.

$ curl localhost:8000/test -X POST -d '{"i": 1, "f": 1.0, "s": "abc", "b": true}'
{"int":1,"float":1.0,"str":"abc","bool":true}

Then, I try to request with invalid body I think. Result is shown below.

$ curl localhost:8000/test -X POST -d '{"i": true, "f": true, "s": true, "b": true}'
{"int":1,"float":1.0,"str":"True","bool":true}

true value is converted to each types(int, float, str).

When I want to validate request body as is, how can I do that?

[tiangolo]

The request is validated by Pydantic. If you want to make sure that each type is exactly that type before doing any conversion, you can create a sub-class for each type, and then use Pydantic validators to ensure that it’s exactly that type.

Check the example for StrictStr. It ensures that the value is an instance of str before trying to convert it to something else: https://pydantic-docs.helpmanual.io/#custom-data-types

[gs11]

Sure, see here https://pydantic-docs.helpmanual.io/usage/types/#strict-types @carlosvbhenriques