Replace noop background updates with DELETE. (#12954)

Removes the `register_noop_background_update` and deletes the background
updates directly in a delta file.

12 files changed, 61 insertions, 118 deletions

diff --git a/synapse/_scripts/synapse_port_db.py b/synapse/_scripts/synapse_port_db.py
index c753dfa7cb..9586086c03 100755
--- a/synapse/_scripts/synapse_port_db.py
+++ b/synapse/_scripts/synapse_port_db.py
@@ -61,7 +61,6 @@ from synapse.storage.databases.main.end_to_end_keys import EndToEndKeyBackground
 from synapse.storage.databases.main.events_bg_updates import (
     EventsBackgroundUpdatesStore,
 )
-from synapse.storage.databases.main.group_server import GroupServerStore
 from synapse.storage.databases.main.media_repository import (
     MediaRepositoryBackgroundUpdateStore,
 )
@@ -218,7 +217,6 @@ class Store(
     PushRuleStore,
     PusherWorkerStore,
     PresenceBackgroundUpdateStore,
-    GroupServerStore,
 ):
     def execute(self, f: Callable[..., R], *args: Any, **kwargs: Any) -> Awaitable[R]:
         return self.db_pool.runInteraction(f.__name__, f, *args, **kwargs)
diff --git a/synapse/storage/background_updates.py b/synapse/storage/background_updates.py
index b1e5208c76..555b4e77d2 100644
--- a/synapse/storage/background_updates.py
+++ b/synapse/storage/background_updates.py
@@ -507,25 +507,6 @@ class BackgroundUpdater:
             update_handler
         )
 
-    def register_noop_background_update(self, update_name: str) -> None:
-        """Register a noop handler for a background update.
-
-        This is useful when we previously did a background update, but no
-        longer wish to do the update. In this case the background update should
-        be removed from the schema delta files, but there may still be some
-        users who have the background update queued, so this method should
-        also be called to clear the update.
-
-        Args:
-            update_name: Name of update
-        """
-
-        async def noop_update(progress: JsonDict, batch_size: int) -> int:
-            await self._end_background_update(update_name)
-            return 1
-
-        self.register_background_update_handler(update_name, noop_update)
-
     def register_background_index_update(
         self,
         update_name: str,
diff --git a/synapse/storage/databases/main/__init__.py b/synapse/storage/databases/main/__init__.py
index 11d9d16c19..9121badb3a 100644
--- a/synapse/storage/databases/main/__init__.py
+++ b/synapse/storage/databases/main/__init__.py
@@ -45,7 +45,6 @@ from .event_push_actions import EventPushActionsStore
 from .events_bg_updates import EventsBackgroundUpdatesStore
 from .events_forward_extremities import EventForwardExtremitiesStore
 from .filtering import FilteringStore
-from .group_server import GroupServerStore
 from .keys import KeyStore
 from .lock import LockStore
 from .media_repository import MediaRepositoryStore
@@ -117,7 +116,6 @@ class DataStore(
     DeviceStore,
     DeviceInboxStore,
     UserDirectoryStore,
-    GroupServerStore,
     UserErasureStore,
     MonthlyActiveUsersWorkerStore,
     StatsStore,
diff --git a/synapse/storage/databases/main/deviceinbox.py b/synapse/storage/databases/main/deviceinbox.py
index 599b418383..422e0e65ca 100644
--- a/synapse/storage/databases/main/deviceinbox.py
+++ b/synapse/storage/databases/main/deviceinbox.py
@@ -834,8 +834,6 @@ class DeviceInboxWorkerStore(SQLBaseStore):
 
 class DeviceInboxBackgroundUpdateStore(SQLBaseStore):
     DEVICE_INBOX_STREAM_ID = "device_inbox_stream_drop"
-    REMOVE_DELETED_DEVICES = "remove_deleted_devices_from_device_inbox"
-    REMOVE_HIDDEN_DEVICES = "remove_hidden_devices_from_device_inbox"
     REMOVE_DEAD_DEVICES_FROM_INBOX = "remove_dead_devices_from_device_inbox"
 
     def __init__(
@@ -857,15 +855,6 @@ class DeviceInboxBackgroundUpdateStore(SQLBaseStore):
             self.DEVICE_INBOX_STREAM_ID, self._background_drop_index_device_inbox
         )
 
-        # Used to be a background update that deletes all device_inboxes for deleted
-        # devices.
-        self.db_pool.updates.register_noop_background_update(
-            self.REMOVE_DELETED_DEVICES
-        )
-        # Used to be a background update that deletes all device_inboxes for hidden
-        # devices.
-        self.db_pool.updates.register_noop_background_update(self.REMOVE_HIDDEN_DEVICES)
-
         self.db_pool.updates.register_background_update_handler(
             self.REMOVE_DEAD_DEVICES_FROM_INBOX,
             self._remove_dead_devices_from_device_inbox,
diff --git a/synapse/storage/databases/main/devices.py b/synapse/storage/databases/main/devices.py
index 71e7863dd8..2414a7dc38 100644
--- a/synapse/storage/databases/main/devices.py
+++ b/synapse/storage/databases/main/devices.py
@@ -1240,15 +1240,6 @@ class DeviceBackgroundUpdateStore(SQLBaseStore):
             self._remove_duplicate_outbound_pokes,
         )
 
-        # a pair of background updates that were added during the 1.14 release cycle,
-        # but replaced with 58/06dlols_unique_idx.py
-        self.db_pool.updates.register_noop_background_update(
-            "device_lists_outbound_last_success_unique_idx",
-        )
-        self.db_pool.updates.register_noop_background_update(
-            "drop_device_lists_outbound_last_success_non_unique_idx",
-        )
-
     async def _drop_device_list_streams_non_unique_indexes(
         self, progress: JsonDict, batch_size: int
     ) -> int:
diff --git a/synapse/storage/databases/main/events_bg_updates.py b/synapse/storage/databases/main/events_bg_updates.py
index d5f0059665..bea34a4c4a 100644
--- a/synapse/storage/databases/main/events_bg_updates.py
+++ b/synapse/storage/databases/main/events_bg_updates.py
@@ -177,11 +177,6 @@ class EventsBackgroundUpdatesStore(SQLBaseStore):
             self._purged_chain_cover_index,
         )
 
-        # The event_thread_relation background update was replaced with the
-        # event_arbitrary_relations one, which handles any relation to avoid
-        # needed to potentially crawl the entire events table in the future.
-        self.db_pool.updates.register_noop_background_update("event_thread_relation")
-
         self.db_pool.updates.register_background_update_handler(
             "event_arbitrary_relations",
             self._event_arbitrary_relations,
diff --git a/synapse/storage/databases/main/group_server.py b/synapse/storage/databases/main/group_server.py
deleted file mode 100644
index c15a7136b6..0000000000
--- a/synapse/storage/databases/main/group_server.py
+++ /dev/null
@@ -1,34 +0,0 @@
-# Copyright 2017 Vector Creations Ltd
-# Copyright 2018 New Vector Ltd
-#
-# 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.
-
-from typing import TYPE_CHECKING
-
-from synapse.storage._base import SQLBaseStore
-from synapse.storage.database import DatabasePool, LoggingDatabaseConnection
-
-if TYPE_CHECKING:
-    from synapse.server import HomeServer
-
-
-class GroupServerStore(SQLBaseStore):
-    def __init__(
-        self,
-        database: DatabasePool,
-        db_conn: LoggingDatabaseConnection,
-        hs: "HomeServer",
-    ):
-        # Register a legacy groups background update as a no-op.
-        database.updates.register_noop_background_update("local_group_updates_index")
-        super().__init__(database, db_conn, hs)
diff --git a/synapse/storage/databases/main/media_repository.py b/synapse/storage/databases/main/media_repository.py
index d028be16de..9b172a64d8 100644
--- a/synapse/storage/databases/main/media_repository.py
+++ b/synapse/storage/databases/main/media_repository.py
@@ -37,9 +37,6 @@ from synapse.types import JsonDict, UserID
 if TYPE_CHECKING:
     from synapse.server import HomeServer
 
-BG_UPDATE_REMOVE_MEDIA_REPO_INDEX_WITHOUT_METHOD = (
-    "media_repository_drop_index_wo_method"
-)
 BG_UPDATE_REMOVE_MEDIA_REPO_INDEX_WITHOUT_METHOD_2 = (
     "media_repository_drop_index_wo_method_2"
 )
@@ -111,13 +108,6 @@ class MediaRepositoryBackgroundUpdateStore(SQLBaseStore):
             unique=True,
         )
 
-        # the original impl of _drop_media_index_without_method was broken (see
-        # https://github.com/matrix-org/synapse/issues/8649), so we replace the original
-        # impl with a no-op and run the fixed migration as
-        # media_repository_drop_index_wo_method_2.
-        self.db_pool.updates.register_noop_background_update(
-            BG_UPDATE_REMOVE_MEDIA_REPO_INDEX_WITHOUT_METHOD
-        )
         self.db_pool.updates.register_background_update_handler(
             BG_UPDATE_REMOVE_MEDIA_REPO_INDEX_WITHOUT_METHOD_2,
             self._drop_media_index_without_method,
diff --git a/synapse/storage/databases/main/registration.py b/synapse/storage/databases/main/registration.py
index 4991360b70..cb63cd9b7d 100644
--- a/synapse/storage/databases/main/registration.py
+++ b/synapse/storage/databases/main/registration.py
@@ -1805,21 +1805,10 @@ class RegistrationBackgroundUpdateStore(RegistrationWorkerStore):
             columns=["creation_ts"],
         )
 
-        # we no longer use refresh tokens, but it's possible that some people
-        # might have a background update queued to build this index. Just
-        # clear the background update.
-        self.db_pool.updates.register_noop_background_update(
-            "refresh_tokens_device_index"
-        )
-
         self.db_pool.updates.register_background_update_handler(
             "users_set_deactivated_flag", self._background_update_set_deactivated_flag
         )
 
-        self.db_pool.updates.register_noop_background_update(
-            "user_threepids_grandfather"
-        )
-
         self.db_pool.updates.register_background_index_update(
             "user_external_ids_user_id_idx",
             index_name="user_external_ids_user_id_idx",
diff --git a/synapse/storage/databases/main/search.py b/synapse/storage/databases/main/search.py
index 78e0773b2a..f6e24b68d2 100644
--- a/synapse/storage/databases/main/search.py
+++ b/synapse/storage/databases/main/search.py
@@ -113,7 +113,6 @@ class SearchBackgroundUpdateStore(SearchWorkerStore):
 
     EVENT_SEARCH_UPDATE_NAME = "event_search"
     EVENT_SEARCH_ORDER_UPDATE_NAME = "event_search_order"
-    EVENT_SEARCH_USE_GIST_POSTGRES_NAME = "event_search_postgres_gist"
     EVENT_SEARCH_USE_GIN_POSTGRES_NAME = "event_search_postgres_gin"
     EVENT_SEARCH_DELETE_NON_STRINGS = "event_search_sqlite_delete_non_strings"
 
@@ -132,15 +131,6 @@ class SearchBackgroundUpdateStore(SearchWorkerStore):
             self.EVENT_SEARCH_ORDER_UPDATE_NAME, self._background_reindex_search_order
         )
 
-        # we used to have a background update to turn the GIN index into a
-        # GIST one; we no longer do that (obviously) because we actually want
-        # a GIN index. However, it's possible that some people might still have
-        # the background update queued, so we register a handler to clear the
-        # background update.
-        self.db_pool.updates.register_noop_background_update(
-            self.EVENT_SEARCH_USE_GIST_POSTGRES_NAME
-        )
-
         self.db_pool.updates.register_background_update_handler(
             self.EVENT_SEARCH_USE_GIN_POSTGRES_NAME, self._background_reindex_gin_search
         )
diff --git a/synapse/storage/databases/main/stats.py b/synapse/storage/databases/main/stats.py
index b95dbef678..538451b05f 100644
--- a/synapse/storage/databases/main/stats.py
+++ b/synapse/storage/databases/main/stats.py
@@ -120,11 +120,6 @@ class StatsStore(StateDeltasStore):
         self.db_pool.updates.register_background_update_handler(
             "populate_stats_process_users", self._populate_stats_process_users
         )
-        # we no longer need to perform clean-up, but we will give ourselves
-        # the potential to reintroduce it in the future – so documentation
-        # will still encourage the use of this no-op handler.
-        self.db_pool.updates.register_noop_background_update("populate_stats_cleanup")
-        self.db_pool.updates.register_noop_background_update("populate_stats_prepare")
 
     async def _populate_stats_process_users(
         self, progress: JsonDict, batch_size: int
diff --git a/synapse/storage/schema/main/delta/70/02remove_noop_background_updates.sql b/synapse/storage/schema/main/delta/70/02remove_noop_background_updates.sql
new file mode 100644
index 0000000000..fa96ac50c2
--- /dev/null
+++ b/synapse/storage/schema/main/delta/70/02remove_noop_background_updates.sql
@@ -0,0 +1,61 @@
+/* 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.
+ */
+
+-- Clean-up background updates which should no longer be run. Previously these
+-- used the (now removed) register_noop_background_update method.
+
+-- Used to be a background update that deletes all device_inboxes for deleted
+-- devices.
+DELETE FROM background_updates WHERE update_name = 'remove_deleted_devices_from_device_inbox';
+-- Used to be a background update that deletes all device_inboxes for hidden
+-- devices.
+DELETE FROM background_updates WHERE update_name = 'remove_hidden_devices_from_device_inbox';
+
+-- A pair of background updates that were added during the 1.14 release cycle,
+-- but replaced with 58/06dlols_unique_idx.py
+DELETE FROM background_updates WHERE update_name = 'device_lists_outbound_last_success_unique_idx';
+DELETE FROM background_updates WHERE update_name = 'drop_device_lists_outbound_last_success_non_unique_idx';
+
+-- The event_thread_relation background update was replaced with the
+-- event_arbitrary_relations one, which handles any relation to avoid
+-- needed to potentially crawl the entire events table in the future.
+DELETE FROM background_updates WHERE update_name = 'event_thread_relation';
+
+-- A legacy groups background update.
+DELETE FROM background_updates WHERE update_name = 'local_group_updates_index';
+
+-- The original impl of _drop_media_index_without_method was broken (see
+-- https://github.com/matrix-org/synapse/issues/8649), so we replace the original
+-- impl with a no-op and run the fixed migration as
+-- media_repository_drop_index_wo_method_2.
+DELETE FROM background_updates WHERE update_name = 'media_repository_drop_index_wo_method';
+
+-- We no longer use refresh tokens, but it's possible that some people
+-- might have a background update queued to build this index. Just
+-- clear the background update.
+DELETE FROM background_updates WHERE update_name = 'refresh_tokens_device_index';
+
+DELETE FROM background_updates WHERE update_name = 'user_threepids_grandfather';
+
+-- We used to have a background update to turn the GIN index into a
+-- GIST one; we no longer do that (obviously) because we actually want
+-- a GIN index. However, it's possible that some people might still have
+-- the background update queued, so we register a handler to clear the
+-- background update.
+DELETE FROM background_updates WHERE update_name = 'event_search_postgres_gist';
+
+-- We no longer need to perform clean-up.
+DELETE FROM background_updates WHERE update_name = 'populate_stats_cleanup';
+DELETE FROM background_updates WHERE update_name = 'populate_stats_prepare';