From fdce83ee60b3b5ffd0c41d112873a4de52b1e640 Mon Sep 17 00:00:00 2001 From: David Robertson Date: Mon, 30 Oct 2023 14:34:37 +0000 Subject: [PATCH] Claim fallback keys in bulk (#16570) --- changelog.d/16570.feature | 1 + synapse/handlers/e2e_keys.py | 14 ++++ synapse/storage/database.py | 10 +++ .../storage/databases/main/end_to_end_keys.py | 60 +++++++++++++++ tests/handlers/test_e2e_keys.py | 77 +++++++++++++++++++ 5 files changed, 162 insertions(+) create mode 100644 changelog.d/16570.feature diff --git a/changelog.d/16570.feature b/changelog.d/16570.feature new file mode 100644 index 000000000..c807945fa --- /dev/null +++ b/changelog.d/16570.feature @@ -0,0 +1 @@ +Improve the performance of claiming encryption keys. diff --git a/synapse/handlers/e2e_keys.py b/synapse/handlers/e2e_keys.py index 8c6432035..91c5fe007 100644 --- a/synapse/handlers/e2e_keys.py +++ b/synapse/handlers/e2e_keys.py @@ -659,6 +659,20 @@ class E2eKeysHandler: timeout: Optional[int], always_include_fallback_keys: bool, ) -> JsonDict: + """ + Args: + query: A chain of maps from (user_id, device_id, algorithm) to the requested + number of keys to claim. + user: The user who is claiming these keys. + timeout: How long to wait for any federation key claim requests before + giving up. + always_include_fallback_keys: always include a fallback key for local users' + devices, even if we managed to claim a one-time-key. + + Returns: a heterogeneous dict with two keys: + one_time_keys: chain of maps user ID -> device ID -> key ID -> key. + failures: map from remote destination to a JsonDict describing the error. + """ local_query: List[Tuple[str, str, str, int]] = [] remote_queries: Dict[str, Dict[str, Dict[str, Dict[str, int]]]] = {} diff --git a/synapse/storage/database.py b/synapse/storage/database.py index b1ece6384..a4e704836 100644 --- a/synapse/storage/database.py +++ b/synapse/storage/database.py @@ -420,6 +420,16 @@ class LoggingTransaction: self._do_execute(self.txn.execute, sql, parameters) def executemany(self, sql: str, *args: Any) -> None: + """Repeatedly execute the same piece of SQL with different parameters. + + See https://peps.python.org/pep-0249/#executemany. Note in particular that + + > Use of this method for an operation which produces one or more result sets + > constitutes undefined behavior + + so you can't use this for e.g. a SELECT, an UPDATE ... RETURNING, or a + DELETE FROM... RETURNING. + """ # TODO: we should add a type for *args here. Looking at Cursor.executemany # and DBAPI2 it ought to be Sequence[_Parameter], but we pass in # Iterable[Iterable[Any]] in execute_batch and execute_values above, which mypy diff --git a/synapse/storage/databases/main/end_to_end_keys.py b/synapse/storage/databases/main/end_to_end_keys.py index f70f95eeb..08385d312 100644 --- a/synapse/storage/databases/main/end_to_end_keys.py +++ b/synapse/storage/databases/main/end_to_end_keys.py @@ -24,6 +24,7 @@ from typing import ( Mapping, Optional, Sequence, + Set, Tuple, Union, cast, @@ -1260,6 +1261,65 @@ class EndToEndKeyWorkerStore(EndToEndKeyBackgroundStore, CacheInvalidationWorker Returns: A map of user ID -> a map device ID -> a map of key ID -> JSON. """ + if isinstance(self.database_engine, PostgresEngine): + return await self.db_pool.runInteraction( + "_claim_e2e_fallback_keys_bulk", + self._claim_e2e_fallback_keys_bulk_txn, + query_list, + db_autocommit=True, + ) + # Use an UPDATE FROM... RETURNING combined with a VALUES block to do + # everything in one query. Note: this is also supported in SQLite 3.33.0, + # (see https://www.sqlite.org/lang_update.html#update_from), but we do not + # have an equivalent of psycopg2's execute_values to do this in one query. + else: + return await self._claim_e2e_fallback_keys_simple(query_list) + + def _claim_e2e_fallback_keys_bulk_txn( + self, + txn: LoggingTransaction, + query_list: Iterable[Tuple[str, str, str, bool]], + ) -> Dict[str, Dict[str, Dict[str, JsonDict]]]: + """Efficient implementation of claim_e2e_fallback_keys for Postgres. + + Safe to autocommit: this is a single query. + """ + results: Dict[str, Dict[str, Dict[str, JsonDict]]] = {} + + sql = """ + WITH claims(user_id, device_id, algorithm, mark_as_used) AS ( + VALUES ? + ) + UPDATE e2e_fallback_keys_json k + SET used = used OR mark_as_used + FROM claims + WHERE (k.user_id, k.device_id, k.algorithm) = (claims.user_id, claims.device_id, claims.algorithm) + RETURNING k.user_id, k.device_id, k.algorithm, k.key_id, k.key_json; + """ + claimed_keys = cast( + List[Tuple[str, str, str, str, str]], + txn.execute_values(sql, query_list), + ) + + seen_user_device: Set[Tuple[str, str]] = set() + for user_id, device_id, algorithm, key_id, key_json in claimed_keys: + device_results = results.setdefault(user_id, {}).setdefault(device_id, {}) + device_results[f"{algorithm}:{key_id}"] = json_decoder.decode(key_json) + + if (user_id, device_id) in seen_user_device: + continue + seen_user_device.add((user_id, device_id)) + self._invalidate_cache_and_stream( + txn, self.get_e2e_unused_fallback_key_types, (user_id, device_id) + ) + + return results + + async def _claim_e2e_fallback_keys_simple( + self, + query_list: Iterable[Tuple[str, str, str, bool]], + ) -> Dict[str, Dict[str, Dict[str, JsonDict]]]: + """Naive, inefficient implementation of claim_e2e_fallback_keys for SQLite.""" results: Dict[str, Dict[str, Dict[str, JsonDict]]] = {} for user_id, device_id, algorithm, mark_as_used in query_list: row = await self.db_pool.simple_select_one( diff --git a/tests/handlers/test_e2e_keys.py b/tests/handlers/test_e2e_keys.py index c5556f284..24e405f42 100644 --- a/tests/handlers/test_e2e_keys.py +++ b/tests/handlers/test_e2e_keys.py @@ -322,6 +322,83 @@ class E2eKeysHandlerTestCase(unittest.HomeserverTestCase): {"failures": {}, "one_time_keys": {local_user: {device_id: fallback_key3}}}, ) + def test_fallback_key_bulk(self) -> None: + """Like test_fallback_key, but claims multiple keys in one handler call.""" + alice = f"@alice:{self.hs.hostname}" + brian = f"@brian:{self.hs.hostname}" + chris = f"@chris:{self.hs.hostname}" + + # Have three users upload fallback keys for two devices. + fallback_keys = { + alice: { + "alice_dev_1": {"alg1:k1": "fallback_key1"}, + "alice_dev_2": {"alg2:k2": "fallback_key2"}, + }, + brian: { + "brian_dev_1": {"alg1:k3": "fallback_key3"}, + "brian_dev_2": {"alg2:k4": "fallback_key4"}, + }, + chris: { + "chris_dev_1": {"alg1:k5": "fallback_key5"}, + "chris_dev_2": {"alg2:k6": "fallback_key6"}, + }, + } + + for user_id, devices in fallback_keys.items(): + for device_id, key_dict in devices.items(): + self.get_success( + self.handler.upload_keys_for_user( + user_id, + device_id, + {"fallback_keys": key_dict}, + ) + ) + + # Each device should have an unused fallback key. + for user_id, devices in fallback_keys.items(): + for device_id in devices: + fallback_res = self.get_success( + self.store.get_e2e_unused_fallback_key_types(user_id, device_id) + ) + expected_algorithm_name = f"alg{device_id[-1]}" + self.assertEqual(fallback_res, [expected_algorithm_name]) + + # Claim the fallback key for one device per user. + claim_res = self.get_success( + self.handler.claim_one_time_keys( + { + alice: {"alice_dev_1": {"alg1": 1}}, + brian: {"brian_dev_2": {"alg2": 1}}, + chris: {"chris_dev_2": {"alg2": 1}}, + }, + self.requester, + timeout=None, + always_include_fallback_keys=False, + ) + ) + expected_claims = { + alice: {"alice_dev_1": {"alg1:k1": "fallback_key1"}}, + brian: {"brian_dev_2": {"alg2:k4": "fallback_key4"}}, + chris: {"chris_dev_2": {"alg2:k6": "fallback_key6"}}, + } + self.assertEqual( + claim_res, + {"failures": {}, "one_time_keys": expected_claims}, + ) + + for user_id, devices in fallback_keys.items(): + for device_id in devices: + fallback_res = self.get_success( + self.store.get_e2e_unused_fallback_key_types(user_id, device_id) + ) + # Claimed fallback keys should no longer show up as unused. + # Unclaimed fallback keys should still be unused. + if device_id in expected_claims[user_id]: + self.assertEqual(fallback_res, []) + else: + expected_algorithm_name = f"alg{device_id[-1]}" + self.assertEqual(fallback_res, [expected_algorithm_name]) + def test_fallback_key_always_returned(self) -> None: local_user = "@boris:" + self.hs.hostname device_id = "xyz"