From 8123b2f90945e6bb3d65cf48730c2133b46d2b9a Mon Sep 17 00:00:00 2001 From: Erik Johnston Date: Mon, 4 May 2020 17:17:45 +0100 Subject: Add MultiWriterIdGenerator. (#7281) This will be used to coordinate stream IDs across multiple writers. Functions as the equivalent of both `StreamIdGenerator` and `SlavedIdTracker`. --- tests/storage/test_id_generators.py | 184 ++++++++++++++++++++++++++++++++++++ 1 file changed, 184 insertions(+) create mode 100644 tests/storage/test_id_generators.py (limited to 'tests/storage') diff --git a/tests/storage/test_id_generators.py b/tests/storage/test_id_generators.py new file mode 100644 index 0000000000..55e9ecf264 --- /dev/null +++ b/tests/storage/test_id_generators.py @@ -0,0 +1,184 @@ +# -*- coding: utf-8 -*- +# Copyright 2020 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. + + +from synapse.storage.database import Database +from synapse.storage.util.id_generators import MultiWriterIdGenerator + +from tests.unittest import HomeserverTestCase +from tests.utils import USE_POSTGRES_FOR_TESTS + + +class MultiWriterIdGeneratorTestCase(HomeserverTestCase): + if not USE_POSTGRES_FOR_TESTS: + skip = "Requires Postgres" + + def prepare(self, reactor, clock, hs): + self.store = hs.get_datastore() + self.db = self.store.db # type: Database + + self.get_success(self.db.runInteraction("_setup_db", self._setup_db)) + + def _setup_db(self, txn): + txn.execute("CREATE SEQUENCE foobar_seq") + txn.execute( + """ + CREATE TABLE foobar ( + stream_id BIGINT NOT NULL, + instance_name TEXT NOT NULL, + data TEXT + ); + """ + ) + + def _create_id_generator(self, instance_name="master") -> MultiWriterIdGenerator: + def _create(conn): + return MultiWriterIdGenerator( + conn, + self.db, + instance_name=instance_name, + table="foobar", + instance_column="instance_name", + id_column="stream_id", + sequence_name="foobar_seq", + ) + + return self.get_success(self.db.runWithConnection(_create)) + + def _insert_rows(self, instance_name: str, number: int): + def _insert(txn): + for _ in range(number): + txn.execute( + "INSERT INTO foobar VALUES (nextval('foobar_seq'), ?)", + (instance_name,), + ) + + self.get_success(self.db.runInteraction("test_single_instance", _insert)) + + def test_empty(self): + """Test an ID generator against an empty database gives sensible + current positions. + """ + + id_gen = self._create_id_generator() + + # The table is empty so we expect an empty map for positions + self.assertEqual(id_gen.get_positions(), {}) + + def test_single_instance(self): + """Test that reads and writes from a single process are handled + correctly. + """ + + # Prefill table with 7 rows written by 'master' + self._insert_rows("master", 7) + + id_gen = self._create_id_generator() + + self.assertEqual(id_gen.get_positions(), {"master": 7}) + self.assertEqual(id_gen.get_current_token("master"), 7) + + # Try allocating a new ID gen and check that we only see position + # advanced after we leave the context manager. + + async def _get_next_async(): + with await id_gen.get_next() as stream_id: + self.assertEqual(stream_id, 8) + + self.assertEqual(id_gen.get_positions(), {"master": 7}) + self.assertEqual(id_gen.get_current_token("master"), 7) + + self.get_success(_get_next_async()) + + self.assertEqual(id_gen.get_positions(), {"master": 8}) + self.assertEqual(id_gen.get_current_token("master"), 8) + + def test_multi_instance(self): + """Test that reads and writes from multiple processes are handled + correctly. + """ + self._insert_rows("first", 3) + self._insert_rows("second", 4) + + first_id_gen = self._create_id_generator("first") + second_id_gen = self._create_id_generator("second") + + self.assertEqual(first_id_gen.get_positions(), {"first": 3, "second": 7}) + self.assertEqual(first_id_gen.get_current_token("first"), 3) + self.assertEqual(first_id_gen.get_current_token("second"), 7) + + # Try allocating a new ID gen and check that we only see position + # advanced after we leave the context manager. + + async def _get_next_async(): + with await first_id_gen.get_next() as stream_id: + self.assertEqual(stream_id, 8) + + self.assertEqual( + first_id_gen.get_positions(), {"first": 3, "second": 7} + ) + + self.get_success(_get_next_async()) + + self.assertEqual(first_id_gen.get_positions(), {"first": 8, "second": 7}) + + # However the ID gen on the second instance won't have seen the update + self.assertEqual(second_id_gen.get_positions(), {"first": 3, "second": 7}) + + # ... but calling `get_next` on the second instance should give a unique + # stream ID + + async def _get_next_async(): + with await second_id_gen.get_next() as stream_id: + self.assertEqual(stream_id, 9) + + self.assertEqual( + second_id_gen.get_positions(), {"first": 3, "second": 7} + ) + + self.get_success(_get_next_async()) + + self.assertEqual(second_id_gen.get_positions(), {"first": 3, "second": 9}) + + # If the second ID gen gets told about the first, it correctly updates + second_id_gen.advance("first", 8) + self.assertEqual(second_id_gen.get_positions(), {"first": 8, "second": 9}) + + def test_get_next_txn(self): + """Test that the `get_next_txn` function works correctly. + """ + + # Prefill table with 7 rows written by 'master' + self._insert_rows("master", 7) + + id_gen = self._create_id_generator() + + self.assertEqual(id_gen.get_positions(), {"master": 7}) + self.assertEqual(id_gen.get_current_token("master"), 7) + + # Try allocating a new ID gen and check that we only see position + # advanced after we leave the context manager. + + def _get_next_txn(txn): + stream_id = id_gen.get_next_txn(txn) + self.assertEqual(stream_id, 8) + + self.assertEqual(id_gen.get_positions(), {"master": 7}) + self.assertEqual(id_gen.get_current_token("master"), 7) + + self.get_success(self.db.runInteraction("test", _get_next_txn)) + + self.assertEqual(id_gen.get_positions(), {"master": 8}) + self.assertEqual(id_gen.get_current_token("master"), 8) -- cgit 1.4.1