synapse/tests/util/test_file_consumer.py
2023-11-21 15:29:58 -05:00

199 lines
6.1 KiB
Python

#
# This file is licensed under the Affero General Public License (AGPL) version 3.
#
# Copyright (C) 2023 New Vector, Ltd
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# See the GNU Affero General Public License for more details:
# <https://www.gnu.org/licenses/agpl-3.0.html>.
#
# Originally licensed under the Apache License, Version 2.0:
# <http://www.apache.org/licenses/LICENSE-2.0>.
#
# [This file includes modifications made by New Vector Limited]
#
#
import threading
from io import BytesIO
from typing import BinaryIO, Generator, Optional, cast
from unittest.mock import NonCallableMock
from zope.interface import implementer
from twisted.internet import defer, reactor as _reactor
from twisted.internet.interfaces import IPullProducer
from synapse.types import ISynapseReactor
from synapse.util.file_consumer import BackgroundFileConsumer
from tests import unittest
reactor = cast(ISynapseReactor, _reactor)
class FileConsumerTests(unittest.TestCase):
@defer.inlineCallbacks
def test_pull_consumer(self) -> Generator["defer.Deferred[object]", object, None]:
string_file = BytesIO()
consumer = BackgroundFileConsumer(string_file, reactor=reactor)
try:
producer = DummyPullProducer()
yield producer.register_with_consumer(consumer)
yield producer.write_and_wait(b"Foo")
self.assertEqual(string_file.getvalue(), b"Foo")
yield producer.write_and_wait(b"Bar")
self.assertEqual(string_file.getvalue(), b"FooBar")
finally:
consumer.unregisterProducer()
yield consumer.wait() # type: ignore[misc]
self.assertTrue(string_file.closed)
@defer.inlineCallbacks
def test_push_consumer(self) -> Generator["defer.Deferred[object]", object, None]:
string_file = BlockingBytesWrite()
consumer = BackgroundFileConsumer(cast(BinaryIO, string_file), reactor=reactor)
try:
producer = NonCallableMock(spec_set=[])
consumer.registerProducer(producer, True)
consumer.write(b"Foo")
yield string_file.wait_for_n_writes(1) # type: ignore[misc]
self.assertEqual(string_file.buffer, b"Foo")
consumer.write(b"Bar")
yield string_file.wait_for_n_writes(2) # type: ignore[misc]
self.assertEqual(string_file.buffer, b"FooBar")
finally:
consumer.unregisterProducer()
yield consumer.wait() # type: ignore[misc]
self.assertTrue(string_file.closed)
@defer.inlineCallbacks
def test_push_producer_feedback(
self,
) -> Generator["defer.Deferred[object]", object, None]:
string_file = BlockingBytesWrite()
consumer = BackgroundFileConsumer(cast(BinaryIO, string_file), reactor=reactor)
try:
producer = NonCallableMock(spec_set=["pauseProducing", "resumeProducing"])
resume_deferred: defer.Deferred = defer.Deferred()
producer.resumeProducing.side_effect = lambda: resume_deferred.callback(
None
)
consumer.registerProducer(producer, True)
number_writes = 0
with string_file.write_lock:
for _ in range(consumer._PAUSE_ON_QUEUE_SIZE):
consumer.write(b"Foo")
number_writes += 1
producer.pauseProducing.assert_called_once()
yield string_file.wait_for_n_writes(number_writes) # type: ignore[misc]
yield resume_deferred
producer.resumeProducing.assert_called_once()
finally:
consumer.unregisterProducer()
yield consumer.wait() # type: ignore[misc]
self.assertTrue(string_file.closed)
@implementer(IPullProducer)
class DummyPullProducer:
def __init__(self) -> None:
self.consumer: Optional[BackgroundFileConsumer] = None
self.deferred: "defer.Deferred[object]" = defer.Deferred()
def resumeProducing(self) -> None:
d = self.deferred
self.deferred = defer.Deferred()
d.callback(None)
def stopProducing(self) -> None:
raise RuntimeError("Unexpected call")
def write_and_wait(self, write_bytes: bytes) -> "defer.Deferred[object]":
assert self.consumer is not None
d = self.deferred
self.consumer.write(write_bytes)
return d
def register_with_consumer(
self, consumer: BackgroundFileConsumer
) -> "defer.Deferred[object]":
d = self.deferred
self.consumer = consumer
self.consumer.registerProducer(self, False)
return d
class BlockingBytesWrite:
def __init__(self) -> None:
self.buffer = b""
self.closed = False
self.write_lock = threading.Lock()
self._notify_write_deferred: Optional[defer.Deferred] = None
self._number_of_writes = 0
def write(self, write_bytes: bytes) -> None:
with self.write_lock:
self.buffer += write_bytes
self._number_of_writes += 1
reactor.callFromThread(self._notify_write)
def close(self) -> None:
self.closed = True
def _notify_write(self) -> None:
"Called by write to indicate a write happened"
with self.write_lock:
if not self._notify_write_deferred:
return
d = self._notify_write_deferred
self._notify_write_deferred = None
d.callback(None)
@defer.inlineCallbacks
def wait_for_n_writes(
self, n: int
) -> Generator["defer.Deferred[object]", object, None]:
"Wait for n writes to have happened"
while True:
with self.write_lock:
if n <= self._number_of_writes:
return
if not self._notify_write_deferred:
self._notify_write_deferred = defer.Deferred()
d = self._notify_write_deferred
yield d