Define delayed event ratelimit category (#18019)

Apply ratelimiting on delayed event management separately from messages.

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---------

Co-authored-by: Andrew Morgan <1342360+anoadragon453@users.noreply.github.com>

1 files changed, 35 insertions, 0 deletions

diff --git a/tests/rest/client/test_rooms.py b/tests/rest/client/test_rooms.py

index a7108b905a..dd8350ddd1 100644
--- a/tests/rest/client/test_rooms.py
+++ b/tests/rest/client/test_rooms.py
@@ -2399,6 +2399,41 @@ class RoomDelayedEventTestCase(RoomBase):
         )
         self.assertEqual(HTTPStatus.OK, channel.code, channel.result)
 
+    @unittest.override_config(
+        {
+            "max_event_delay_duration": "24h",
+            "rc_message": {"per_second": 1, "burst_count": 2},
+        }
+    )
+    def test_add_delayed_event_ratelimit(self) -> None:
+        """Test that requests to schedule new delayed events are ratelimited by a RateLimiter,
+        which ratelimits them correctly, including by not limiting when the requester is
+        exempt from ratelimiting.
+        """
+
+        # Test that new delayed events are correctly ratelimited.
+        args = (
+            "POST",
+            (
+                "rooms/%s/send/m.room.message?org.matrix.msc4140.delay=2000"
+                % self.room_id
+            ).encode("ascii"),
+            {"body": "test", "msgtype": "m.text"},
+        )
+        channel = self.make_request(*args)
+        self.assertEqual(HTTPStatus.OK, channel.code, channel.result)
+        channel = self.make_request(*args)
+        self.assertEqual(HTTPStatus.TOO_MANY_REQUESTS, channel.code, channel.result)
+
+        # Add the current user to the ratelimit overrides, allowing them no ratelimiting.
+        self.get_success(
+            self.hs.get_datastores().main.set_ratelimit_for_user(self.user_id, 0, 0)
+        )
+
+        # Test that the new delayed events aren't ratelimited anymore.
+        channel = self.make_request(*args)
+        self.assertEqual(HTTPStatus.OK, channel.code, channel.result)
+
 
 class RoomSearchTestCase(unittest.HomeserverTestCase):
     servlets = [