[QUESTION]Using a single Body parameter, the JSON format will report an error

Description

Using a single Body parameter, the JSON format will report an error

Additional context

@router.post("/test/")
async def test(abd: str=Body(...)):
    print(abd)               ---error

@router.post("/test/")
async def test(abd: str=Body(...), acd: str=Body(...)):
    print(abd)               ---right

Using a single Body parameter, the JSON format will report an error

[BillGrim]

@ wxq0309您如何解决此问题？我有相同的问题

This can be done by setting the Embed property

item: Item = Body(..., embed=True)

example:
from fastapi import Body, FastAPI
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    description: str = None
    price: float
    tax: float = None


@app.put("/items/{item_id}")
async def update_item(*, item_id: int, item: Item = Body(..., embed=True)):
    results = {"item_id": item_id, "item": item}
    return results

In my opinion, the condition of your solution is already different from the problem you met, which is “Single parameter declared with fastapi.Body requests str formatted rather than json formatted request body”.

I read the official doc singular-values-in-body, but the demo contains extra paramters(request param, pydantic model).

In my case, I have many apis that needs only a single post body param.

So Is there a way to declare a single param in body of a post api without using pydantic?

[tiangolo]

Thanks for the discussion here everyone! And thanks @wxq0309 for closing the issue and reporting back your solution. 👍