I am writing an app where I need to have two completely different set of response structures depending on logic.
Is there any way to handle this so that I can have two different response models serialized, validated and returned and reflect in OpenAPI JSON?
I am using pydantic to write models.
Thank you!
Yes this is possible. You can use Union for that in the response_model= parameter in your path decorator (I used the new python 3.10 style below). Here is a full example, this will work as is.
from typing import Union
from fastapi import FastAPI, Query
from pydantic import BaseModel
class responseA(BaseModel):
name: str
class responseB(BaseModel):
id: int
app = FastAPI()
@app.get("/", response_model=responseA|responseB )
def base(q: int|str = Query(None)):
if q and isinstance(q, str):
return responseA(name=q)
if q and isinstance(q, int):
return responseB(id=q)
raise HTTPException(status_code=400, detail="No q param provided")
if __name__ == "__main__":
import uvicorn
uvicorn.run(app, host="0.0.0.0", port=8000, )
Result in your documentation:
