First Check

• I added a very descriptive title here.
• I used the GitHub search to find a similar question and didn't find it.
• I searched the FastAPI documentation, with the integrated search.
• I already searched in Google "How to X in FastAPI" and didn't find any information.
• I already read and followed all the tutorial in the docs and didn't find an answer.
• I already checked if it is not related to FastAPI but to Pydantic.
• I already checked if it is not related to FastAPI but to Swagger UI.
• I already checked if it is not related to FastAPI but to ReDoc.

Commit to Help

• I commit to help with one of those options 👆

Example Code

import uvicorn
from typing import Literal

from fastapi import FastAPI, Query
from pydantic import BaseModel, ConfigDict, Field
from pydantic.alias_generators import to_camel

app = FastAPI()


class FilterParams(BaseModel):
    model_config = ConfigDict(alias_generator=to_camel)

    limit: int = Field(100, gt=0, le=100)
    offset: int = Field(0, ge=0)
    order_by: Literal['created_at', 'updated_at'] = 'created_at'
    tags: list[str] = []


@app.get('/items/')
async def read_items(filter_query: FilterParams = Query()):
    return filter_query


if __name__ == '__main__':
    uvicorn.run(app='app:app')

Description

Running the code in the example above, I encountered an incorrect result when accessing http://127.0.0.1:8000/items/?offset=1&orderBy=updated_at in the browser, orderBy did not receive successfully.

{
    "limit": 100,
    "offset": 1,
    "orderBy": "created_at",
    "tags": []
}

The correct result should be as follows

{
    "limit": 100,
    "offset": 1,
    "orderBy": "updated_at",
    "tags": []
}

Operating System

Windows

Operating System Details

No response

FastAPI Version

0.115.0

Pydantic Version

2.9.2

Python Version

3.9.19

Additional Context

No response