From 373c485d8c7f39206bac60c6ef313b4a1978bbc0 Mon Sep 17 00:00:00 2001 From: Sean Quah <8349537+squahtx@users.noreply.github.com> Date: Fri, 9 Dec 2022 23:02:11 +0000 Subject: [PATCH] Handle half-created indices in receipts index background update (#14650) When Synapse is terminated while running the background update to create the `receipts_graph` or `receipts_linearized` indexes, the indexes may be successfully created (or marked as invalid on postgres) while the background update remains unfinished. When Synapse next starts up, the background update will fail because the index already exists, or exists but is invalid on postgres. Use the existing code to create indices in background updates, since it handles these edge cases. Signed-off-by: Sean Quah --- changelog.d/14650.bugfix | 2 + synapse/storage/background_updates.py | 55 ++++++++++++++++++---- synapse/storage/databases/main/receipts.py | 51 +++++--------------- 3 files changed, 60 insertions(+), 48 deletions(-) create mode 100644 changelog.d/14650.bugfix diff --git a/changelog.d/14650.bugfix b/changelog.d/14650.bugfix new file mode 100644 index 000000000..5e18641bf --- /dev/null +++ b/changelog.d/14650.bugfix @@ -0,0 +1,2 @@ +Fix a bug introduced in Synapse 1.72.0 where the background updates to add non-thread unique indexes on receipts would fail if they were previously interrupted. + diff --git a/synapse/storage/background_updates.py b/synapse/storage/background_updates.py index 2056ecb2c..a99aea892 100644 --- a/synapse/storage/background_updates.py +++ b/synapse/storage/background_updates.py @@ -544,6 +544,48 @@ class BackgroundUpdater: The named index will be dropped upon completion of the new index. """ + async def updater(progress: JsonDict, batch_size: int) -> int: + await self.create_index_in_background( + index_name=index_name, + table=table, + columns=columns, + where_clause=where_clause, + unique=unique, + psql_only=psql_only, + replaces_index=replaces_index, + ) + await self._end_background_update(update_name) + return 1 + + self._background_update_handlers[update_name] = _BackgroundUpdateHandler( + updater, oneshot=True + ) + + async def create_index_in_background( + self, + index_name: str, + table: str, + columns: Iterable[str], + where_clause: Optional[str] = None, + unique: bool = False, + psql_only: bool = False, + replaces_index: Optional[str] = None, + ) -> None: + """Add an index in the background. + + Args: + update_name: update_name to register for + index_name: name of index to add + table: table to add index to + columns: columns/expressions to include in index + where_clause: A WHERE clause to specify a partial unique index. + unique: true to make a UNIQUE index + psql_only: true to only create this index on psql databases (useful + for virtual sqlite tables) + replaces_index: The name of an index that this index replaces. + The named index will be dropped upon completion of the new index. + """ + def create_index_psql(conn: Connection) -> None: conn.rollback() # postgres insists on autocommit for the index @@ -618,16 +660,11 @@ class BackgroundUpdater: else: runner = create_index_sqlite - async def updater(progress: JsonDict, batch_size: int) -> int: - if runner is not None: - logger.info("Adding index %s to %s", index_name, table) - await self.db_pool.runWithConnection(runner) - await self._end_background_update(update_name) - return 1 + if runner is None: + return - self._background_update_handlers[update_name] = _BackgroundUpdateHandler( - updater, oneshot=True - ) + logger.info("Adding index %s to %s", index_name, table) + await self.db_pool.runWithConnection(runner) async def _end_background_update(self, update_name: str) -> None: """Removes a completed background update task from the queue. diff --git a/synapse/storage/databases/main/receipts.py b/synapse/storage/databases/main/receipts.py index a580e4bdd..e06725f69 100644 --- a/synapse/storage/databases/main/receipts.py +++ b/synapse/storage/databases/main/receipts.py @@ -924,39 +924,6 @@ class ReceiptsBackgroundUpdateStore(SQLBaseStore): return batch_size - async def _create_receipts_index(self, index_name: str, table: str) -> None: - """Adds a unique index on `(room_id, receipt_type, user_id)` to the given - receipts table, for non-thread receipts.""" - - def _create_index(conn: LoggingDatabaseConnection) -> None: - conn.rollback() - - # we have to set autocommit, because postgres refuses to - # CREATE INDEX CONCURRENTLY without it. - if isinstance(self.database_engine, PostgresEngine): - conn.set_session(autocommit=True) - - try: - c = conn.cursor() - - # Now that the duplicates are gone, we can create the index. - concurrently = ( - "CONCURRENTLY" - if isinstance(self.database_engine, PostgresEngine) - else "" - ) - sql = f""" - CREATE UNIQUE INDEX {concurrently} {index_name} - ON {table}(room_id, receipt_type, user_id) - WHERE thread_id IS NULL - """ - c.execute(sql) - finally: - if isinstance(self.database_engine, PostgresEngine): - conn.set_session(autocommit=False) - - await self.db_pool.runWithConnection(_create_index) - async def _background_receipts_linearized_unique_index( self, progress: dict, batch_size: int ) -> int: @@ -999,9 +966,12 @@ class ReceiptsBackgroundUpdateStore(SQLBaseStore): _remote_duplicate_receipts_txn, ) - await self._create_receipts_index( - "receipts_linearized_unique_index", - "receipts_linearized", + await self.db_pool.updates.create_index_in_background( + index_name="receipts_linearized_unique_index", + table="receipts_linearized", + columns=["room_id", "receipt_type", "user_id"], + where_clause="thread_id IS NULL", + unique=True, ) await self.db_pool.updates._end_background_update( @@ -1050,9 +1020,12 @@ class ReceiptsBackgroundUpdateStore(SQLBaseStore): _remote_duplicate_receipts_txn, ) - await self._create_receipts_index( - "receipts_graph_unique_index", - "receipts_graph", + await self.db_pool.updates.create_index_in_background( + index_name="receipts_graph_unique_index", + table="receipts_graph", + columns=["room_id", "receipt_type", "user_id"], + where_clause="thread_id IS NULL", + unique=True, ) await self.db_pool.updates._end_background_update(