caches: Only take the realm_id, not the Realm, as a cache key function.

This saves a hit to the database to fetch the Realm of a UserProfile
that we are trying to flush.

zerver/actions/message_send.py

@@ -122,7 +122,7 @@ def compute_jabber_user_fullname(email: str) -> str:
 def get_user_profile_delivery_email_cache_key(
     realm: Realm, email: str, email_to_fullname: Callable[[str], str]
 ) -> str:
-    return user_profile_delivery_email_cache_key(email, realm)
+    return user_profile_delivery_email_cache_key(email, realm.id)
 
 
 @cache_with_key(

zerver/actions/user_settings.py

@@ -109,7 +109,7 @@ def send_delivery_email_update_events(
 
 @transaction.atomic(savepoint=False)
 def do_change_user_delivery_email(user_profile: UserProfile, new_email: str) -> None:
-    delete_user_profile_caches([user_profile], user_profile.realm)
+    delete_user_profile_caches([user_profile], user_profile.realm_id)
 
     user_profile.delivery_email = new_email
     if user_profile.email_address_is_realm_public():

zerver/lib/cache.py

@@ -431,8 +431,8 @@ def user_profile_cache_key(email: str, realm: "Realm") -> str:
     return user_profile_cache_key_id(email, realm.id)
 
 
-def user_profile_delivery_email_cache_key(delivery_email: str, realm: "Realm") -> str:
+def user_profile_delivery_email_cache_key(delivery_email: str, realm_id: int) -> str:
-    return f"user_profile_by_delivery_email:{hashlib.sha1(delivery_email.strip().encode()).hexdigest()}:{realm.id}"
+    return f"user_profile_by_delivery_email:{hashlib.sha1(delivery_email.strip().encode()).hexdigest()}:{realm_id}"
 
 
 def bot_profile_cache_key(email: str, realm_id: int) -> str:
@@ -515,7 +515,7 @@ def bot_dicts_in_realm_cache_key(realm_id: int) -> str:
     return f"bot_dicts_in_realm:{realm_id}"
 
 
-def delete_user_profile_caches(user_profiles: Iterable["UserProfile"], realm: "Realm") -> None:
+def delete_user_profile_caches(user_profiles: Iterable["UserProfile"], realm_id: int) -> None:
     # Imported here to avoid cyclic dependency.
     from zerver.lib.users import get_all_api_keys
     from zerver.models.users import is_cross_realm_bot_email
@@ -524,11 +524,11 @@ def delete_user_profile_caches(user_profiles: Iterable["UserProfile"], realm: "R
     for user_profile in user_profiles:
         keys.append(user_profile_by_id_cache_key(user_profile.id))
         keys += map(user_profile_by_api_key_cache_key, get_all_api_keys(user_profile))
-        keys.append(user_profile_cache_key(user_profile.email, realm))
+        keys.append(user_profile_cache_key_id(user_profile.email, realm_id))
-        keys.append(user_profile_delivery_email_cache_key(user_profile.delivery_email, realm))
+        keys.append(user_profile_delivery_email_cache_key(user_profile.delivery_email, realm_id))
         if user_profile.is_bot and is_cross_realm_bot_email(user_profile.email):
             # Handle clearing system bots from their special cache.
-            keys.append(bot_profile_cache_key(user_profile.email, realm.id))
+            keys.append(bot_profile_cache_key(user_profile.email, realm_id))
             keys.append(get_cross_realm_dicts_key())
 
     cache_delete_many(keys)
@@ -563,7 +563,7 @@ def flush_user_profile(
     **kwargs: object,
 ) -> None:
     user_profile = instance
-    delete_user_profile_caches([user_profile], user_profile.realm)
+    delete_user_profile_caches([user_profile], user_profile.realm_id)
 
     # Invalidate our active_users_in_realm info dict if any user has changed
     # the fields in the dict or become (in)active
@@ -603,7 +603,7 @@ def flush_realm(
 ) -> None:
     realm = instance
     users = realm.get_active_users()
-    delete_user_profile_caches(users, realm)
+    delete_user_profile_caches(users, realm.id)
 
     if (
         from_deletion

zerver/lib/cache_helpers.py

@@ -19,7 +19,7 @@ from zerver.lib.cache import (
     get_remote_cache_requests,
     get_remote_cache_time,
     user_profile_by_api_key_cache_key,
-    user_profile_cache_key,
+    user_profile_cache_key_id,
 )
 from zerver.lib.safe_session_cached_db import SessionStore
 from zerver.lib.sessions import session_engine
@@ -33,7 +33,7 @@ def user_cache_items(
 ) -> None:
     for api_key in get_all_api_keys(user_profile):
         items_for_remote_cache[user_profile_by_api_key_cache_key(api_key)] = (user_profile,)
-    items_for_remote_cache[user_profile_cache_key(user_profile.email, user_profile.realm)] = (
+    items_for_remote_cache[user_profile_cache_key_id(user_profile.email, user_profile.realm_id)] = (
         user_profile,
     )
     # We have other user_profile caches, but none of them are on the

zerver/tests/test_soft_deactivation.py

@@ -398,7 +398,7 @@ class SoftDeactivationMessageTest(ZulipTestCase):
         idle_user_msg_list = get_user_messages(long_term_idle_user)
         idle_user_msg_count = len(idle_user_msg_list)
         self.assertNotEqual(idle_user_msg_list[-1], sent_message)
-        with self.assert_database_query_count(6):
+        with self.assert_database_query_count(5):
             add_missing_messages(long_term_idle_user)
         idle_user_msg_list = get_user_messages(long_term_idle_user)
         self.assert_length(idle_user_msg_list, idle_user_msg_count + 1)