From 9e617cd4c2da527caf93799e286b42352ad492d2 Mon Sep 17 00:00:00 2001
From: Erik Johnston <erik@matrix.org>
Date: Mon, 13 Feb 2017 13:50:03 +0000
Subject: [PATCH] Cache get_presence storage

---
 synapse/handlers/presence.py                  |  2 +-
 synapse/replication/slave/storage/presence.py |  4 +++-
 synapse/storage/presence.py                   | 14 +++++++++++---
 3 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/synapse/handlers/presence.py b/synapse/handlers/presence.py
index fdfce2a88c..da610e430f 100644
--- a/synapse/handlers/presence.py
+++ b/synapse/handlers/presence.py
@@ -531,7 +531,7 @@ class PresenceHandler(object):
             # There are things not in our in memory cache. Lets pull them out of
             # the database.
             res = yield self.store.get_presence_for_users(missing)
-            states.update({state.user_id: state for state in res})
+            states.update(res)
 
             missing = [user_id for user_id, state in states.items() if not state]
             if missing:
diff --git a/synapse/replication/slave/storage/presence.py b/synapse/replication/slave/storage/presence.py
index 703f4a49bf..40f6c9a386 100644
--- a/synapse/replication/slave/storage/presence.py
+++ b/synapse/replication/slave/storage/presence.py
@@ -18,6 +18,7 @@ from ._slaved_id_tracker import SlavedIdTracker
 
 from synapse.util.caches.stream_change_cache import StreamChangeCache
 from synapse.storage import DataStore
+from synapse.storage.presence import PresenceStore
 
 
 class SlavedPresenceStore(BaseSlavedStore):
@@ -35,7 +36,8 @@ class SlavedPresenceStore(BaseSlavedStore):
 
     _get_active_presence = DataStore._get_active_presence.__func__
     take_presence_startup_info = DataStore.take_presence_startup_info.__func__
-    get_presence_for_users = DataStore.get_presence_for_users.__func__
+    _get_presence_for_user = PresenceStore.__dict__["_get_presence_for_user"]
+    get_presence_for_users = PresenceStore.__dict__["get_presence_for_users"]
 
     def get_current_presence_token(self):
         return self._presence_id_gen.get_current_token()
diff --git a/synapse/storage/presence.py b/synapse/storage/presence.py
index 7460f98a1f..4d1590d2b4 100644
--- a/synapse/storage/presence.py
+++ b/synapse/storage/presence.py
@@ -15,7 +15,7 @@
 
 from ._base import SQLBaseStore
 from synapse.api.constants import PresenceState
-from synapse.util.caches.descriptors import cached, cachedInlineCallbacks
+from synapse.util.caches.descriptors import cached, cachedInlineCallbacks, cachedList
 
 from collections import namedtuple
 from twisted.internet import defer
@@ -85,6 +85,9 @@ class PresenceStore(SQLBaseStore):
                 self.presence_stream_cache.entity_has_changed,
                 state.user_id, stream_id,
             )
+            self._invalidate_cache_and_stream(
+                txn, self._get_presence_for_user, (state.user_id,)
+            )
 
         # Actually insert new rows
         self._simple_insert_many_txn(
@@ -143,7 +146,12 @@ class PresenceStore(SQLBaseStore):
             "get_all_presence_updates", get_all_presence_updates_txn
         )
 
-    @defer.inlineCallbacks
+    @cached()
+    def _get_presence_for_user(self, user_id):
+        raise NotImplementedError()
+
+    @cachedList(cached_method_name="_get_presence_for_user", list_name="user_ids",
+                num_args=1, inlineCallbacks=True)
     def get_presence_for_users(self, user_ids):
         rows = yield self._simple_select_many_batch(
             table="presence_stream",
@@ -165,7 +173,7 @@ class PresenceStore(SQLBaseStore):
         for row in rows:
             row["currently_active"] = bool(row["currently_active"])
 
-        defer.returnValue([UserPresenceState(**row) for row in rows])
+        defer.returnValue({row["user_id"]: UserPresenceState(**row) for row in rows})
 
     def get_current_presence_token(self):
         return self._presence_id_gen.get_current_token()