Initial commit

backend/app/access.py

@@ -0,0 +1,30 @@
+from sqlmodel import Session, select
+
+from app.models import Dish, DishShare
+
+
+def dish_for_barcode(session: Session, barcode: str) -> Dish | None:
+    if not barcode.startswith("dish-"):
+        return None
+    return session.exec(select(Dish).where(Dish.product_barcode == barcode)).first()
+
+
+def user_can_access_dish(session: Session, dish: Dish, user_id: int) -> bool:
+    if dish.user_id == user_id:
+        return True
+    return (
+        session.exec(
+            select(DishShare).where(
+                DishShare.dish_id == dish.id,
+                DishShare.shared_with_user_id == user_id,
+            )
+        ).first()
+        is not None
+    )
+
+
+def product_barcode_accessible(session: Session, barcode: str, user_id: int) -> bool:
+    dish = dish_for_barcode(session, barcode)
+    if dish is None:
+        return True
+    return user_can_access_dish(session, dish, user_id)