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Not able to handle URL-encoded GET parameters - Response code 422 - Expected?

See original GitHub issue

Is it expected that FastAPI cannot handle URL-encoded GET parameters? I searched the docs and via google but couldn’t find any hints why this is or how to change the behaviour.

See the example below. I’m trying to pass float numbers as GET parameters with the . being URL-encoded. I’m getting the response that the number isn’t a valid float.

Example

from pydantic import BaseModel
from fastapi import FastAPI

app = FastAPI()

class LongitudinalDiameterAndQuantity(BaseModel):
    diameter: float
    quantity_a: float
    quantity_b: float

@app.get("/column/longitudinal/diameter_quantity", response_model=LongitudinalDiameterAndQuantity)
def read_root(As: float, a: float, b: float):
    # TODO: Feed parameters into ML model and get results
    return LongitudinalDiameterAndQuantity(diameter=As, quantity_a=a, quantity_b=b)

Description

Non-URL-Encoded - working

URL: http://localhost:8000/column/longitudinal/diameter_quantity?As=1.2&a=1.2&b=1.2 As expected: Response code 200, content: {"diameter":1.2,"quantity_a":1.2,"quantity_b":1.2}

URL-Encoded - not working

URL: http://localhost:8000/column/longitudinal/diameter_quantity?As=1%2C2&a=1%2C2&b=1%2C2 Not expected: Response code 422, content:

{
   "detail":[
      {
         "loc":[
            "query",
            "As"
         ],
         "msg":"value is not a valid float",
         "type":"type_error.float"
      },
      {
         "loc":[
            "query",
            "a"
         ],
         "msg":"value is not a valid float",
         "type":"type_error.float"
      },
      {
         "loc":[
            "query",
            "b"
         ],
         "msg":"value is not a valid float",
         "type":"type_error.float"
      }
   ]
}