How to post dictionary data type in FastAPI Request Forms ?

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Example Code

@menu.post("/add-menu")
async def addmenu(
    ItemName: str = Form(...),
    ItemShortDesc: str = Form(...),
    ItemPrice: str = Form(...),
    ItemCategory: list = Form(...),
    ItemStatus: str = Form(...),
    ItemChoices: list[dict[str,str]] = Form(...)):
    
    return ItemChoices

Description

POST Method using FastAPI Request Form Request Body | application/x-www-form-urlencoded

I am trying to do,

1. “list” of “dict” using request form - error Code:422
2. Only “dict” using request form - error Code:422
3. without “dict” - Its Worked

I got the below error, error Code:422

“detail”: [ { “loc”: [ “body”, “ItemChoices”, 0 ], “msg”: “value is not a valid dict”, “type”: “type_error.dict” } ] }

How can I use “dict” or “list” of “dict” in FastAPI request form? Please help me out of any possible chance.

Operating System

Linux

Operating System Details

No response

FastAPI Version

0.73.0

Python Version

python3.9

Additional Context

[upeshjindal]

@growwithsundar You cannot send the data as a json in form fields. It needs to be sent as a stringified JSON and on the FastAPI side, you need convert this to your desired object.

Form fields work okay for simple datatypes.

See the link for reference: https://stackoverflow.com/questions/60127234/how-to-use-a-pydantic-model-with-form-data-in-fastapi

[growwithsundar]

@growwithsundar You cannot send the data as a json in form fields. It needs to be sent as a stringified JSON and on the FastAPI side, you need convert this to your desired object.

Form fields work okay for simple datatypes.

See the link for reference: https://stackoverflow.com/questions/60127234/how-to-use-a-pydantic-model-with-form-data-in-fastapi

Thanks it worked