is it possible in a post to select the body from the value of another parameter?

[DSO01]

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• I already checked if it is not related to FastAPI but to Swagger UI.
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Example Code

class Item(BaseModel):
    name: str
    description: str | None = None
    cpu: int
    ram: int

@deploy.post('/create')
def deploy_item_in_vra(item:Item,catalog,env:VraEnv = VraEnv.dev):
    response = vra_deploy_item(env=env,item=item)
    return response

Description

is it possible in fastapi to select a body according to the value of another parameter?

Operating System

Windows

Operating System Details

No response

FastAPI Version

0.105.0

Pydantic Version

2.5.2

Python Version

3.10.6

Additional Context

is it possible in fastapi to select a body according to the value of another parameter?

[heysaeid]

I don't understand why such an action is necessary, but you should have it in the following form (if I have understood the meaning correctly):

from config import settings

class Item1(BaseModel):
    name: str
    description: str | None = None
    cpu: int
    ram: int
    env: str

class Item2(BaseModel):
    name: str
    description: str | None = None
    env: str
 
models = {
    "dev": Item1,
    "stage": Item2,
}

@app.post("/create")
def deploy_item_in_vra(item: models[settings.env] = Depends()):
    response = vra_deploy_item(item=item)
    return response

[DSO01]

Hello heysaeid, thankyou for your answer.
I am using fastapi as a catalog of tools and not as an API. that is the reason why I would like to have functions in the swagger parameters.

I try to use your code but I have an issue with the package config I can not find "settings" module
the line "from config import settings" failed even if I install the config package "pip install config"

[heysaeid]

In general, by adding the setting in the following manner, you can make use of it. However, for more information, please refer to https://fastapi.tiangolo.com/advanced/settings/

from pydantic import BaseSettings

class Settings(BaseSettings):
    env: str = "DEV"

settings = Settings()

[DSO01]

thankyou, unfortunatly this can not be a solution for me cause settings variable is initialized each time the main:app is reinitiated
what I need is a variable that is reinitiated each time I launch a specific function
I have found an other way to solve it. when using main:app --reload
my first function creates a file that initiate the pydantic Models needed in the second function
the file when created or modified activates the reload of the API and the second function can accès the new model as a parameter type

the issue now is for my prod catalog which is started without reload in a windows service.
is it possible to reload a pydantic model from a file in a child function of the API?

[YuriiMotov]

Let's close this for now to keep the discussions clean and organized.
If you’ve found a solution, please share it here.
If you still need help, feel free to let us know.