Don't cache UserPresence info.

(imported from commit ff590bdf5d84bb9b3cedc561c2f2fbf7f7592a66)

zerver/lib/actions.py

@@ -34,7 +34,7 @@ from django.utils import timezone
 from zerver.lib.create_user import create_user
 from zerver.lib import bugdown
 from zerver.lib.cache import cache_with_key, cache_set, \
-    user_profile_by_email_cache_key, status_dict_cache_key, cache_set_many, \
+    user_profile_by_email_cache_key, cache_set_many, \
     cache_delete, cache_delete_many, message_cache_key
 from zerver.decorator import get_user_profile_by_email, json_to_list, JsonableError, \
      statsd_increment
@@ -1367,7 +1367,6 @@ def gather_subscriptions(user_profile):
 
     return (sorted(subscribed), sorted(unsubscribed))
 
-@cache_with_key(status_dict_cache_key, timeout=60)
 def get_status_dict(requesting_user_profile):
     # Return no status info for MIT
     if requesting_user_profile.realm.domain == 'mit.edu':

zerver/lib/cache.py

@@ -250,19 +250,5 @@ def update_user_profile_cache(sender, **kwargs):
     if kwargs['update_fields'] is None or "alert_words" in kwargs['update_fields']:
         djcache.delete(KEY_PREFIX + realm_alert_words_cache_key(user_profile.realm))
 
-def status_dict_cache_key_for_realm_id(realm_id):
-    return "status_dict:%d" % (realm_id,)
-
-def status_dict_cache_key(user_profile):
-    return status_dict_cache_key_for_realm_id(user_profile.realm_id)
-
-def update_user_presence_cache(sender, **kwargs):
-    # For any status update, flush the user's realm's entry in the
-    # UserPresence cache to avoid giving out stale state.  Since we
-    # get a lot of presence updates, we are likely to get cache misses
-    # when new messages come in, but the query is pretty quick.
-    user_profile = kwargs['instance'].user_profile
-    djcache.delete(KEY_PREFIX + status_dict_cache_key(user_profile))
-
 def realm_alert_words_cache_key(realm):
     return "realm_alert_words:%s" % (realm.domain,)

zerver/lib/cache_helpers.py

@@ -9,8 +9,7 @@ from zerver.models import Message, UserProfile, Stream, get_stream_cache_key, \
     Huddle, huddle_hash_cache_key
 from zerver.lib.cache import cache_with_key, cache_set, message_cache_key, \
     user_profile_by_email_cache_key, user_profile_by_id_cache_key, \
-    get_memcached_time, get_memcached_requests, cache_set_many, \
-    status_dict_cache_key_for_realm_id
+    get_memcached_time, get_memcached_requests, cache_set_many
 from django.utils.importlib import import_module
 from django.contrib.sessions.models import Session
 import logging
@@ -49,9 +48,6 @@ def huddle_cache_items(items_for_memcached, huddle):
 def recipient_cache_items(items_for_memcached, recipient):
     items_for_memcached[get_recipient_cache_key(recipient.type, recipient.type_id)] = (recipient,)
 
-def presence_cache_items(items_for_memcached, status_dict):
-    items_for_memcached[status_dict_cache_key_for_realm_id(status_dict[0])] = (status_dict[1],)
-
 session_engine = import_module(settings.SESSION_ENGINE)
 def session_cache_items(items_for_memcached, session):
     store = session_engine.SessionStore(session_key=session.session_key)

zerver/models.py

@@ -6,7 +6,7 @@ from django.contrib.auth.models import AbstractBaseUser, UserManager, \
     PermissionsMixin
 from zerver.lib.cache import cache_with_key, update_user_profile_cache, \
     user_profile_by_id_cache_key, user_profile_by_email_cache_key, \
-    update_user_presence_cache, generic_bulk_cached_fetch, cache_set, \
+    generic_bulk_cached_fetch, cache_set, \
     display_recipient_cache_key
 from zerver.lib.utils import make_safe_digest, generate_random_token
 from django.db import transaction, IntegrityError
@@ -765,10 +765,6 @@ class UserPresence(models.Model):
     class Meta:
         unique_together = ("user_profile", "client")
 
-# Flush the cached user status_dict whenever a user's presence
-# changes
-post_save.connect(update_user_presence_cache, sender=UserPresence)
-
 class DefaultStream(models.Model):
     realm = models.ForeignKey(Realm)
     stream = models.ForeignKey(Stream)

zerver/tornado_callbacks.py

@@ -8,8 +8,7 @@ from zerver.models import Message, UserProfile, UserMessage, \
 
 from zerver.decorator import JsonableError
 from zerver.lib.cache import cache_get_many, message_cache_key, \
-    user_profile_by_id_cache_key, cache_save_user_profile, \
-    status_dict_cache_key_for_realm_id
+    user_profile_by_id_cache_key, cache_save_user_profile
 from zerver.lib.cache_helpers import cache_save_message
 from zerver.lib.queue import queue_json_publish
 from zerver.lib.event_queue import get_client_descriptors_for_user