Add support to purge rows from MSC2716 and other tables when purging a room (#13825)

`event_failed_pull_attempts` added in #13589

MSC2716 related tables added in:

 - https://github.com/matrix-org/synapse/pull/10245/files#diff-3d42dfb44d02f7de3aada105e0bdc1cc9dd7f953cbf0f36c5d0f50827bf0320aR1
    - Renamed in https://github.com/matrix-org/synapse/pull/10838/files#diff-2730bfbe9e688b55e46f9371aefe67dac2bd2b2b7d9d6b92774eea1fcfae156dR1
 - https://github.com/matrix-org/synapse/pull/10498/files#diff-c52bbfbb5921a3f6f023b24343668479d966fac164f13b7c39d2197ce3afa7a5R1

Author: MadLittleMods

changelog.d/13825.bugfix

@@ -0,0 +1 @@
+Delete associated data from `event_failed_pull_attempts`, `insertion_events`, `insertion_event_extremities`, `insertion_event_extremities`, `insertion_event_extremities` when purging the room.

synapse/storage/databases/main/purge_events.py

@@ -419,6 +419,7 @@ def _purge_room_txn(self, txn: LoggingTransaction, room_id: str) -> List[int]:
             "event_forward_extremities",
             "event_push_actions",
             "event_search",
+            "event_failed_pull_attempts",
             "partial_state_events",
             "events",
             "federation_inbound_events_staging",
@@ -441,6 +442,10 @@ def _purge_room_txn(self, txn: LoggingTransaction, room_id: str) -> List[int]:
             "e2e_room_keys",
             "event_push_summary",
             "pusher_throttle",
+            "insertion_events",
+            "insertion_event_extremities",
+            "insertion_event_edges",
+            "batch_events",
             "room_account_data",
             "room_tags",
             # "rooms" happens last, to keep the foreign keys in the other tables

synapse/storage/schema/__init__.py

@@ -83,6 +83,8 @@
       event_push_summary, receipts_linearized, and receipts_graph.
     - Add table `event_failed_pull_attempts` to keep track when we fail to pull
       events over federation.
+    - Add indexes to various tables (`event_failed_pull_attempts`, `insertion_events`,
+      `batch_events`) to make it easy to delete all associated rows when purging a room.
 """
 
 

synapse/storage/schema/main/delta/73/02room_id_indexes_for_purging.sql

@@ -0,0 +1,22 @@
+/* Copyright 2022 The Matrix.org Foundation C.I.C
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- Add index so we can easily purge all rows from a given `room_id`
+CREATE INDEX IF NOT EXISTS event_failed_pull_attempts_room_id ON event_failed_pull_attempts(room_id);
+
+-- MSC2716 related tables:
+-- Add indexes so we can easily purge all rows from a given `room_id`
+CREATE INDEX IF NOT EXISTS insertion_events_room_id ON insertion_events(room_id);
+CREATE INDEX IF NOT EXISTS batch_events_room_id ON batch_events(room_id);