feat: added "last-modified" header to supported record types (#1379)

* fixed type error

* exposed created/updated timestamps to shopping list schema

* added custom route to mix in "last-modified" header when available in CRUD routes

* mixed in MealieCrudRoute to APIRouters

* added HEAD route for shopping lists/list-items

* replaced default serializer with FastAPI's

mealie/routes/_base/routers.py

@@ -1,6 +1,11 @@
-from typing import Optional
+import json
+from collections.abc import Callable
+from enum import Enum
+from json.decoder import JSONDecodeError
+from typing import Optional, Union
 
-from fastapi import APIRouter, Depends
+from fastapi import APIRouter, Depends, Request, Response
+from fastapi.routing import APIRoute
 
 from mealie.core.dependencies import get_admin_user, get_current_user
 
@@ -8,20 +13,34 @@ from mealie.core.dependencies import get_admin_user, get_current_user
 class AdminAPIRouter(APIRouter):
     """Router for functions to be protected behind admin authentication"""
 
-    def __init__(
-        self,
-        tags: Optional[list[str]] = None,
-        prefix: str = "",
-    ):
-        super().__init__(tags=tags, prefix=prefix, dependencies=[Depends(get_admin_user)])
+    def __init__(self, tags: Optional[list[Union[str, Enum]]] = None, prefix: str = "", **kwargs):
+        super().__init__(tags=tags, prefix=prefix, dependencies=[Depends(get_admin_user)], **kwargs)
 
 
 class UserAPIRouter(APIRouter):
     """Router for functions to be protected behind user authentication"""
 
-    def __init__(
-        self,
-        tags: Optional[list[str]] = None,
-        prefix: str = "",
-    ):
-        super().__init__(tags=tags, prefix=prefix, dependencies=[Depends(get_current_user)])
+    def __init__(self, tags: Optional[list[Union[str, Enum]]] = None, prefix: str = "", **kwargs):
+        super().__init__(tags=tags, prefix=prefix, dependencies=[Depends(get_current_user)], **kwargs)
+
+
+class MealieCrudRoute(APIRoute):
+    """Route class to include the last-modified header when returning a MealieModel, when available"""
+
+    def get_route_handler(self) -> Callable:
+        original_route_handler = super().get_route_handler()
+
+        async def custom_route_handler(request: Request) -> Response:
+            try:
+                response = await original_route_handler(request)
+                response_body = json.loads(response.body)
+                if type(response_body) == dict:
+                    if last_modified := response_body.get("updateAt"):
+                        response.headers["last-modified"] = last_modified
+
+            except JSONDecodeError:
+                pass
+
+            return response
+
+        return custom_route_handler