From c80a9fe13dc098037a37bb0920a00b2c8cb53174 Mon Sep 17 00:00:00 2001
From: Erik Johnston <erik@matrix.org>
Date: Thu, 30 Jan 2020 15:06:58 +0000
Subject: [PATCH] When a client asks for remote keys check if should resync.
(#6797)
If we detect that the remote users' keys may have changed then we should
attempt to resync against the remote server rather than using the
(potentially) stale local cache.
---
changelog.d/6797.misc | 1 +
synapse/storage/data_stores/main/devices.py | 32 +++++++++++++++++++--
2 files changed, 30 insertions(+), 3 deletions(-)
create mode 100644 changelog.d/6797.misc
diff --git a/changelog.d/6797.misc b/changelog.d/6797.misc
new file mode 100644
index 000000000..e9127bac5
--- /dev/null
+++ b/changelog.d/6797.misc
@@ -0,0 +1 @@
+When a client asks for a remote user's device keys check if the local cache for that user has been marked as potentially stale.
diff --git a/synapse/storage/data_stores/main/devices.py b/synapse/storage/data_stores/main/devices.py
index 30bf66b2b..a34415ff1 100644
--- a/synapse/storage/data_stores/main/devices.py
+++ b/synapse/storage/data_stores/main/devices.py
@@ -32,7 +32,7 @@ from synapse.logging.opentracing import (
from synapse.metrics.background_process_metrics import run_as_background_process
from synapse.storage._base import SQLBaseStore, db_to_json, make_in_list_sql_clause
from synapse.storage.database import Database
-from synapse.types import get_verify_key_from_cross_signing_key
+from synapse.types import Collection, get_verify_key_from_cross_signing_key
from synapse.util.caches.descriptors import (
Cache,
cached,
@@ -443,8 +443,15 @@ class DeviceWorkerStore(SQLBaseStore):
"""
user_ids = set(user_id for user_id, _ in query_list)
user_map = yield self.get_device_list_last_stream_id_for_remotes(list(user_ids))
- user_ids_in_cache = set(
- user_id for user_id, stream_id in user_map.items() if stream_id
+
+ # We go and check if any of the users need to have their device lists
+ # resynced. If they do then we remove them from the cached list.
+ users_needing_resync = yield self.get_user_ids_requiring_device_list_resync(
+ user_ids
+ )
+ user_ids_in_cache = (
+ set(user_id for user_id, stream_id in user_map.items() if stream_id)
+ - users_needing_resync
)
user_ids_not_in_cache = user_ids - user_ids_in_cache
@@ -641,6 +648,25 @@ class DeviceWorkerStore(SQLBaseStore):
return results
+ @defer.inlineCallbacks
+ def get_user_ids_requiring_device_list_resync(self, user_ids: Collection[str]):
+ """Given a list of remote users return the list of users that we
+ should resync the device lists for.
+
+ Returns:
+ Deferred[Set[str]]
+ """
+
+ rows = yield self.db.simple_select_many_batch(
+ table="device_lists_remote_resync",
+ column="user_id",
+ iterable=user_ids,
+ retcols=("user_id",),
+ desc="get_user_ids_requiring_device_list_resync",
+ )
+
+ return {row["user_id"] for row in rows}
+
def mark_remote_user_device_cache_as_stale(self, user_id: str):
"""Records that the server has reason to believe the cache of the devices
for the remote users is out of date.