FastAPI/Pydantic accept arbitrary post request body?

Question

I want to create a FastAPI endpoint that just accepts an arbitrary post request body and returns it.

If I send {"foo" : "bar"} , I want to get {"foo" : "bar"} back. But I also want to be able to send {"foo1" : "bar1", "foo2" : "bar2"} and get that back.

I tried:

from fastapi import FastAPI
app = FastAPI()

app.post("/")
async def handle(request: BaseModel):
    return request

But that returns an empty dictionary, no matter what I send it.

Any ideas?

Answer 1

You can use type hint Dict[Any, Any] to tell FastAPI you're expecting any valid JSON:

from typing import Any, Dict
from fastapi import FastAPI

app = FastAPI()

@app.post("/")
async def handle(request: Dict[Any, Any]):
    return request