FastAPI deployed to an azure web app - getting environments variables

I have deployed a FastAPI application to an azure web app. I would like to access the environment variables from the web app in fast api. Is that possible and if yes or do you do that? Both from azure ofcource, but also how do you manage locally when developing. As we speak I am only using a basic hello world template:

from fastapi import FastAPI,Request
from fastapi.middleware.cors import CORSMiddleware
from fastapi_azure_auth import SingleTenantAzureAuthorizationCodeBearer
import uvicorn
from fastapi import FastAPI, Security
import os
from typing import Dict

from settings import Settings

from pydantic import AnyHttpUrl,BaseModel

from contextlib import asynccontextmanager
from typing import AsyncGenerator

from fastapi_azure_auth.user import User

settings = Settings()

@asynccontextmanager
async def lifespan(app: FastAPI) -> AsyncGenerator[None, None]:
    """
    Load OpenID config on startup.
    """
    await azure_scheme.openid_config.load_config()
    yield


app = FastAPI(
    swagger_ui_oauth2_redirect_url='/oauth2-redirect',
    swagger_ui_init_oauth={
        'usePkceWithAuthorizationCodeGrant': True,
        'clientId': settings.OPENAPI_CLIENT_ID,
        'scopes': settings.SCOPE_NAME,
    },
)

if settings.BACKEND_CORS_ORIGINS:
    app.add_middleware(
        CORSMiddleware,
        allow_origins=[str(origin) for origin in settings.BACKEND_CORS_ORIGINS],
        allow_credentials=True,
        allow_methods=['*'],
        allow_headers=['*'],
    )

azure_scheme = SingleTenantAzureAuthorizationCodeBearer(
    app_client_id=settings.APP_CLIENT_ID,
    tenant_id=settings.TENANT_ID,
    scopes=settings.SCOPES,
)

class User(BaseModel):
    name: str
    roles: list[str] = []


@app.get("/", dependencies=[Security(azure_scheme)])
async def root():
    print("Yo bro")
    return {"whoIsTheBest": "DNA Team is"}

@app.get("/test", dependencies=[Security(azure_scheme)])
async def root():
    print("Yo test")
    return {"whoIsTheBest": "DNA Team is!"}

@app.get("/me", dependencies=[Security(azure_scheme)])
async def me(request: Request):
    print("Me")
    return User(roles=request.state.user.roles,name=request.state.user.name)

if __name__ == '__main__':
    uvicorn.run('main:app', reload=True) 

   

Thanks @jonrsharpe for comment.

I created simple FastAPI app to fetch environment variables and deployed to Azure App service.

The os module is important for accessing the environment variables in Python.

We need to install python-dotenv package to retrieve environment variables from .env file.

.env:

GREETING_MESSAGE=Hello, World!

main. py

from fastapi import FastAPI
import os
from dotenv import load_dotenv
load_dotenv()
app = FastAPI()
@app.get("/")
def read_root():
    greeting = os.getenv("GREETING_MESSAGE", "Hello from FastAPI!")
    return {"message": greeting}

requirements.txt:

fastapi
uvicorn
python-dotenv

Below is my local Output:

After deploying to azure I added below Startup Command in Configuration section of Azure Web app.

 gunicorn --worker-class uvicorn.workers.UvicornWorker --timeout 600 --access-logfile '-' --error-logfile '-' main:app

To securely access environment variables in Azure, add them to the Environment Variables section of the Azure Web App, as shown below.

Azure Output: