Implement NamespacedCache.get_or_set, reduce default caching time

src/pretix/base/cache.py

@@ -1,6 +1,6 @@
 import hashlib
 import time
-from typing import Dict, List
+from typing import Callable, Dict, List
 
 from django.core.cache import caches
 from django.db.models import Model
@@ -41,12 +41,19 @@ class NamespacedCache:
             prefix = int(time.time())
             self.cache.set(self.prefixkey, prefix)
 
-    def set(self, key: str, value: str, timeout: int=3600):
+    def set(self, key: str, value: str, timeout: int=300):
         return self.cache.set(self._prefix_key(key), value, timeout)
 
     def get(self, key: str) -> str:
         return self.cache.get(self._prefix_key(key, known_prefix=self._last_prefix))
 
+    def get_or_set(self, key: str, default: Callable, timeout=300) -> str:
+        return self.cache.get_or_set(
+            self._prefix_key(key, known_prefix=self._last_prefix),
+            default=default,
+            timeout=timeout
+        )
+
     def get_many(self, keys: List[str]) -> Dict[str, str]:
         values = self.cache.get_many([self._prefix_key(key) for key in keys])
         newvalues = {}
@@ -54,7 +61,7 @@ class NamespacedCache:
             newvalues[self._strip_prefix(k)] = v
         return newvalues
 
-    def set_many(self, values: Dict[str, str], timeout=3600):
+    def set_many(self, values: Dict[str, str], timeout=300):
         newvalues = {}
         for k, v in values.items():
             newvalues[self._prefix_key(k)] = v