synapse-product/tests/util/caches/test_deferred_cache.py
Richard van der Hoff 903d11c43a
Add DeferredCache.get_immediate method (#8568)
* Add `DeferredCache.get_immediate` method

A bunch of things that are currently calling `DeferredCache.get` are only
really interested in the result if it's completed. We can optimise and simplify
this case.

* Remove unused 'default' parameter to DeferredCache.get()

* another get_immediate instance
2020-10-19 15:00:12 +01:00

157 lines
4.2 KiB
Python

# -*- 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.
import unittest
from functools import partial
from twisted.internet import defer
from synapse.util.caches.deferred_cache import DeferredCache
class DeferredCacheTestCase(unittest.TestCase):
def test_empty(self):
cache = DeferredCache("test")
failed = False
try:
cache.get("foo")
except KeyError:
failed = True
self.assertTrue(failed)
def test_hit(self):
cache = DeferredCache("test")
cache.prefill("foo", 123)
self.assertEquals(cache.get("foo"), 123)
def test_get_immediate(self):
cache = DeferredCache("test")
d1 = defer.Deferred()
cache.set("key1", d1)
# get_immediate should return default
v = cache.get_immediate("key1", 1)
self.assertEqual(v, 1)
# now complete the set
d1.callback(2)
# get_immediate should return result
v = cache.get_immediate("key1", 1)
self.assertEqual(v, 2)
def test_invalidate(self):
cache = DeferredCache("test")
cache.prefill(("foo",), 123)
cache.invalidate(("foo",))
failed = False
try:
cache.get(("foo",))
except KeyError:
failed = True
self.assertTrue(failed)
def test_invalidate_all(self):
cache = DeferredCache("testcache")
callback_record = [False, False]
def record_callback(idx):
callback_record[idx] = True
# add a couple of pending entries
d1 = defer.Deferred()
cache.set("key1", d1, partial(record_callback, 0))
d2 = defer.Deferred()
cache.set("key2", d2, partial(record_callback, 1))
# lookup should return observable deferreds
self.assertFalse(cache.get("key1").has_called())
self.assertFalse(cache.get("key2").has_called())
# let one of the lookups complete
d2.callback("result2")
# for now at least, the cache will return real results rather than an
# observabledeferred
self.assertEqual(cache.get("key2"), "result2")
# now do the invalidation
cache.invalidate_all()
# lookup should fail
with self.assertRaises(KeyError):
cache.get("key1")
with self.assertRaises(KeyError):
cache.get("key2")
# both callbacks should have been callbacked
self.assertTrue(callback_record[0], "Invalidation callback for key1 not called")
self.assertTrue(callback_record[1], "Invalidation callback for key2 not called")
# letting the other lookup complete should do nothing
d1.callback("result1")
with self.assertRaises(KeyError):
cache.get("key1", None)
def test_eviction(self):
cache = DeferredCache(
"test", max_entries=2, apply_cache_factor_from_config=False
)
cache.prefill(1, "one")
cache.prefill(2, "two")
cache.prefill(3, "three") # 1 will be evicted
failed = False
try:
cache.get(1)
except KeyError:
failed = True
self.assertTrue(failed)
cache.get(2)
cache.get(3)
def test_eviction_lru(self):
cache = DeferredCache(
"test", max_entries=2, apply_cache_factor_from_config=False
)
cache.prefill(1, "one")
cache.prefill(2, "two")
# Now access 1 again, thus causing 2 to be least-recently used
cache.get(1)
cache.prefill(3, "three")
failed = False
try:
cache.get(2)
except KeyError:
failed = True
self.assertTrue(failed)
cache.get(1)
cache.get(3)