made things prettier

app/utils.py

@@ -1,11 +1,12 @@
 import os
 import logging
-
+from cachetools import TTLCache, cached
+from eventlet.semaphore import Semaphore
 from flask import request, session, redirect, url_for, current_app, abort, make_response
 from typing import cast
 from itsdangerous import BadSignature, URLSafeSerializer
 from xkcdpass import xkcd_password
-from functools import wraps, lru_cache
+from functools import wraps
 from urllib.parse import urlparse, urljoin
 
 from .models import Deck, InfoBanner, Token, db, Course
@@ -13,7 +14,8 @@ from .models import Deck, InfoBanner, Token, db, Course
 
 # Create a module-level logger per Flask/Python standards
 logger = logging.getLogger(__name__)
-
+_deck_cache = TTLCache(maxsize=1000, ttl=10)
+_deck_cache_lock = Semaphore()
 
 
 def init_password_generator():
@@ -190,12 +192,14 @@ def token_required(f):
     return decorated_function
 
 
-# Cache the last 1000 lookups per worker. 
-@lru_cache(maxsize=1000)
+
+
+
+@cached(_deck_cache, lock=_deck_cache_lock)
 def get_cached_deck_info(token_id, course_folder, deck_slug):
     """
     Returns a dictionary of primitive types for route authorization and routing.
-    Never return raw SQLAlchemy models from an lru_cache!
+    Never return raw SQLAlchemy models from a cache!
     """
     # 1. Fetch Token
     token = db.session.get(Token, token_id)
@@ -221,7 +225,6 @@ def get_cached_deck_info(token_id, course_folder, deck_slug):
     # 4. Check Authorization
     is_unlocked = deck_slug in [d.deck for d in token.decks]
 
-    # Return only primitive data (bools, strings) so the cache is thread-safe!
     return {
         "auth": is_unlocked,
         "course_exists": True,