Fix room creation being rate limited too aggressively since Synapse v1.69.0. (#14314)

* Introduce a test for the old behaviour which we want to restore

* Reintroduce the old behaviour in a simpler way

* Newsfile

Signed-off-by: Olivier Wilkinson (reivilibre) <oliverw@matrix.org>

* Use 1 credit instead of 2 for creating a room: be more lenient than before

Notably, the UI in Element Web was still broken after restoring to prior behaviour.

After discussion, we agreed that it would be sensible to increase the limit.

Signed-off-by: Olivier Wilkinson (reivilibre) <oliverw@matrix.org>

1 files changed, 7 insertions, 1 deletions

diff --git a/synapse/api/ratelimiting.py b/synapse/api/ratelimiting.py
index 044c7d4926..511790c7c5 100644
--- a/synapse/api/ratelimiting.py
+++ b/synapse/api/ratelimiting.py
@@ -343,6 +343,7 @@ class RequestRatelimiter:
         requester: Requester,
         update: bool = True,
         is_admin_redaction: bool = False,
+        n_actions: int = 1,
     ) -> None:
         """Ratelimits requests.
 
@@ -355,6 +356,8 @@ class RequestRatelimiter:
             is_admin_redaction: Whether this is a room admin/moderator
                 redacting an event. If so then we may apply different
                 ratelimits depending on config.
+            n_actions: Multiplier for the number of actions to apply to the
+                rate limiter at once.
 
         Raises:
             LimitExceededError if the request should be ratelimited
@@ -383,7 +386,9 @@ class RequestRatelimiter:
         if is_admin_redaction and self.admin_redaction_ratelimiter:
             # If we have separate config for admin redactions, use a separate
             # ratelimiter as to not have user_ids clash
-            await self.admin_redaction_ratelimiter.ratelimit(requester, update=update)
+            await self.admin_redaction_ratelimiter.ratelimit(
+                requester, update=update, n_actions=n_actions
+            )
         else:
             # Override rate and burst count per-user
             await self.request_ratelimiter.ratelimit(
@@ -391,4 +396,5 @@ class RequestRatelimiter:
                 rate_hz=messages_per_second,
                 burst_count=burst_count,
                 update=update,
+                n_actions=n_actions,
             )