Add authorization

src/allmende_payment_system/app.py

@@ -1,9 +1,25 @@
-# backend/app/main.py
-from fastapi import FastAPI, Request
+import os
+from typing import Annotated
+
+from fastapi import Depends, FastAPI, HTTPException, Request
 from fastapi.staticfiles import StaticFiles
 from fastapi.templating import Jinja2Templates
 
-app = FastAPI()
+
+async def get_user(request: Request) -> dict:
+
+    if username := os.environ.get("APS_username", None):
+        return {"username": username}
+    if "ynh_user" not in request.headers:
+        raise HTTPException(status_code=401, detail="Missing ynh_user header")
+    return {"username": request.headers["ynh_user"]}
+
+
+UserDep = Annotated[dict, Depends(get_user)]
+
+
+app = FastAPI(dependencies=[Depends(get_user)])
+
 templates = Jinja2Templates(directory="src/allmende_payment_system/templates")
 app.mount(
     "/static",