forked-synapse/tests/util/caches/test_descriptors.py
Sean Quah 2fcf4b3f6c
Add cancellation support to @cached and @cachedList decorators (#12183)
These decorators mostly support cancellation already. Add cancellation
tests and fix use of finished logging contexts by delaying cancellation,
as suggested by @erikjohnston.

Signed-off-by: Sean Quah <seanq@element.io>
2022-03-14 19:04:29 +00:00

1011 lines
31 KiB
Python

# Copyright 2016 OpenMarket Ltd
# Copyright 2018 New Vector Ltd
#
# 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 logging
from typing import Set
from unittest import mock
from twisted.internet import defer, reactor
from twisted.internet.defer import CancelledError, Deferred
from synapse.api.errors import SynapseError
from synapse.logging.context import (
SENTINEL_CONTEXT,
LoggingContext,
PreserveLoggingContext,
current_context,
make_deferred_yieldable,
)
from synapse.util.caches import descriptors
from synapse.util.caches.descriptors import cached, cachedList, lru_cache
from tests import unittest
from tests.test_utils import get_awaitable_result
logger = logging.getLogger(__name__)
class LruCacheDecoratorTestCase(unittest.TestCase):
def test_base(self):
class Cls:
def __init__(self):
self.mock = mock.Mock()
@lru_cache()
def fn(self, arg1, arg2):
return self.mock(arg1, arg2)
obj = Cls()
obj.mock.return_value = "fish"
r = obj.fn(1, 2)
self.assertEqual(r, "fish")
obj.mock.assert_called_once_with(1, 2)
obj.mock.reset_mock()
# a call with different params should call the mock again
obj.mock.return_value = "chips"
r = obj.fn(1, 3)
self.assertEqual(r, "chips")
obj.mock.assert_called_once_with(1, 3)
obj.mock.reset_mock()
# the two values should now be cached
r = obj.fn(1, 2)
self.assertEqual(r, "fish")
r = obj.fn(1, 3)
self.assertEqual(r, "chips")
obj.mock.assert_not_called()
def run_on_reactor():
d = defer.Deferred()
reactor.callLater(0, d.callback, 0)
return make_deferred_yieldable(d)
class DescriptorTestCase(unittest.TestCase):
@defer.inlineCallbacks
def test_cache(self):
class Cls:
def __init__(self):
self.mock = mock.Mock()
@descriptors.cached()
def fn(self, arg1, arg2):
return self.mock(arg1, arg2)
obj = Cls()
obj.mock.return_value = "fish"
r = yield obj.fn(1, 2)
self.assertEqual(r, "fish")
obj.mock.assert_called_once_with(1, 2)
obj.mock.reset_mock()
# a call with different params should call the mock again
obj.mock.return_value = "chips"
r = yield obj.fn(1, 3)
self.assertEqual(r, "chips")
obj.mock.assert_called_once_with(1, 3)
obj.mock.reset_mock()
# the two values should now be cached
r = yield obj.fn(1, 2)
self.assertEqual(r, "fish")
r = yield obj.fn(1, 3)
self.assertEqual(r, "chips")
obj.mock.assert_not_called()
@defer.inlineCallbacks
def test_cache_num_args(self):
"""Only the first num_args arguments should matter to the cache"""
class Cls:
def __init__(self):
self.mock = mock.Mock()
@descriptors.cached(num_args=1)
def fn(self, arg1, arg2):
return self.mock(arg1, arg2)
obj = Cls()
obj.mock.return_value = "fish"
r = yield obj.fn(1, 2)
self.assertEqual(r, "fish")
obj.mock.assert_called_once_with(1, 2)
obj.mock.reset_mock()
# a call with different params should call the mock again
obj.mock.return_value = "chips"
r = yield obj.fn(2, 3)
self.assertEqual(r, "chips")
obj.mock.assert_called_once_with(2, 3)
obj.mock.reset_mock()
# the two values should now be cached; we should be able to vary
# the second argument and still get the cached result.
r = yield obj.fn(1, 4)
self.assertEqual(r, "fish")
r = yield obj.fn(2, 5)
self.assertEqual(r, "chips")
obj.mock.assert_not_called()
@defer.inlineCallbacks
def test_cache_uncached_args(self):
"""
Only the arguments not named in uncached_args should matter to the cache
Note that this is identical to test_cache_num_args, but provides the
arguments differently.
"""
class Cls:
# Note that it is important that this is not the last argument to
# test behaviour of skipping arguments properly.
@descriptors.cached(uncached_args=("arg2",))
def fn(self, arg1, arg2, arg3):
return self.mock(arg1, arg2, arg3)
def __init__(self):
self.mock = mock.Mock()
obj = Cls()
obj.mock.return_value = "fish"
r = yield obj.fn(1, 2, 3)
self.assertEqual(r, "fish")
obj.mock.assert_called_once_with(1, 2, 3)
obj.mock.reset_mock()
# a call with different params should call the mock again
obj.mock.return_value = "chips"
r = yield obj.fn(2, 3, 4)
self.assertEqual(r, "chips")
obj.mock.assert_called_once_with(2, 3, 4)
obj.mock.reset_mock()
# the two values should now be cached; we should be able to vary
# the second argument and still get the cached result.
r = yield obj.fn(1, 4, 3)
self.assertEqual(r, "fish")
r = yield obj.fn(2, 5, 4)
self.assertEqual(r, "chips")
obj.mock.assert_not_called()
@defer.inlineCallbacks
def test_cache_kwargs(self):
"""Test that keyword arguments are treated properly"""
class Cls:
def __init__(self):
self.mock = mock.Mock()
@descriptors.cached()
def fn(self, arg1, kwarg1=2):
return self.mock(arg1, kwarg1=kwarg1)
obj = Cls()
obj.mock.return_value = "fish"
r = yield obj.fn(1, kwarg1=2)
self.assertEqual(r, "fish")
obj.mock.assert_called_once_with(1, kwarg1=2)
obj.mock.reset_mock()
# a call with different params should call the mock again
obj.mock.return_value = "chips"
r = yield obj.fn(1, kwarg1=3)
self.assertEqual(r, "chips")
obj.mock.assert_called_once_with(1, kwarg1=3)
obj.mock.reset_mock()
# the values should now be cached.
r = yield obj.fn(1, kwarg1=2)
self.assertEqual(r, "fish")
# We should be able to not provide kwarg1 and get the cached value back.
r = yield obj.fn(1)
self.assertEqual(r, "fish")
# Keyword arguments can be in any order.
r = yield obj.fn(kwarg1=2, arg1=1)
self.assertEqual(r, "fish")
obj.mock.assert_not_called()
def test_cache_with_sync_exception(self):
"""If the wrapped function throws synchronously, things should continue to work"""
class Cls:
@cached()
def fn(self, arg1):
raise SynapseError(100, "mai spoon iz too big!!1")
obj = Cls()
# this should fail immediately
d = obj.fn(1)
self.failureResultOf(d, SynapseError)
# ... leaving the cache empty
self.assertEqual(len(obj.fn.cache.cache), 0)
# and a second call should result in a second exception
d = obj.fn(1)
self.failureResultOf(d, SynapseError)
def test_cache_with_async_exception(self):
"""The wrapped function returns a failure"""
class Cls:
result = None
call_count = 0
@cached()
def fn(self, arg1):
self.call_count += 1
return self.result
obj = Cls()
callbacks: Set[str] = set()
# set off an asynchronous request
obj.result = origin_d = defer.Deferred()
d1 = obj.fn(1, on_invalidate=lambda: callbacks.add("d1"))
self.assertFalse(d1.called)
# a second request should also return a deferred, but should not call the
# function itself.
d2 = obj.fn(1, on_invalidate=lambda: callbacks.add("d2"))
self.assertFalse(d2.called)
self.assertEqual(obj.call_count, 1)
# no callbacks yet
self.assertEqual(callbacks, set())
# the original request fails
e = Exception("bzz")
origin_d.errback(e)
# ... which should cause the lookups to fail similarly
self.assertIs(self.failureResultOf(d1, Exception).value, e)
self.assertIs(self.failureResultOf(d2, Exception).value, e)
# ... and the callbacks to have been, uh, called.
self.assertEqual(callbacks, {"d1", "d2"})
# ... leaving the cache empty
self.assertEqual(len(obj.fn.cache.cache), 0)
# and a second call should work as normal
obj.result = defer.succeed(100)
d3 = obj.fn(1)
self.assertEqual(self.successResultOf(d3), 100)
self.assertEqual(obj.call_count, 2)
def test_cache_logcontexts(self):
"""Check that logcontexts are set and restored correctly when
using the cache."""
complete_lookup = defer.Deferred()
class Cls:
@descriptors.cached()
def fn(self, arg1):
@defer.inlineCallbacks
def inner_fn():
with PreserveLoggingContext():
yield complete_lookup
return 1
return inner_fn()
@defer.inlineCallbacks
def do_lookup():
with LoggingContext("c1") as c1:
r = yield obj.fn(1)
self.assertEqual(current_context(), c1)
return r
def check_result(r):
self.assertEqual(r, 1)
obj = Cls()
# set off a deferred which will do a cache lookup
d1 = do_lookup()
self.assertEqual(current_context(), SENTINEL_CONTEXT)
d1.addCallback(check_result)
# and another
d2 = do_lookup()
self.assertEqual(current_context(), SENTINEL_CONTEXT)
d2.addCallback(check_result)
# let the lookup complete
complete_lookup.callback(None)
return defer.gatherResults([d1, d2])
def test_cache_logcontexts_with_exception(self):
"""Check that the cache sets and restores logcontexts correctly when
the lookup function throws an exception"""
class Cls:
@descriptors.cached()
def fn(self, arg1):
@defer.inlineCallbacks
def inner_fn():
# we want this to behave like an asynchronous function
yield run_on_reactor()
raise SynapseError(400, "blah")
return inner_fn()
@defer.inlineCallbacks
def do_lookup():
with LoggingContext("c1") as c1:
try:
d = obj.fn(1)
self.assertEqual(
current_context(),
SENTINEL_CONTEXT,
)
yield d
self.fail("No exception thrown")
except SynapseError:
pass
self.assertEqual(current_context(), c1)
# the cache should now be empty
self.assertEqual(len(obj.fn.cache.cache), 0)
obj = Cls()
# set off a deferred which will do a cache lookup
d1 = do_lookup()
self.assertEqual(current_context(), SENTINEL_CONTEXT)
return d1
@defer.inlineCallbacks
def test_cache_default_args(self):
class Cls:
def __init__(self):
self.mock = mock.Mock()
@descriptors.cached()
def fn(self, arg1, arg2=2, arg3=3):
return self.mock(arg1, arg2, arg3)
obj = Cls()
obj.mock.return_value = "fish"
r = yield obj.fn(1, 2, 3)
self.assertEqual(r, "fish")
obj.mock.assert_called_once_with(1, 2, 3)
obj.mock.reset_mock()
# a call with same params shouldn't call the mock again
r = yield obj.fn(1, 2)
self.assertEqual(r, "fish")
obj.mock.assert_not_called()
obj.mock.reset_mock()
# a call with different params should call the mock again
obj.mock.return_value = "chips"
r = yield obj.fn(2, 3)
self.assertEqual(r, "chips")
obj.mock.assert_called_once_with(2, 3, 3)
obj.mock.reset_mock()
# the two values should now be cached
r = yield obj.fn(1, 2)
self.assertEqual(r, "fish")
r = yield obj.fn(2, 3)
self.assertEqual(r, "chips")
obj.mock.assert_not_called()
def test_cache_iterable(self):
class Cls:
def __init__(self):
self.mock = mock.Mock()
@descriptors.cached(iterable=True)
def fn(self, arg1, arg2):
return self.mock(arg1, arg2)
obj = Cls()
obj.mock.return_value = ["spam", "eggs"]
r = obj.fn(1, 2)
self.assertEqual(r.result, ["spam", "eggs"])
obj.mock.assert_called_once_with(1, 2)
obj.mock.reset_mock()
# a call with different params should call the mock again
obj.mock.return_value = ["chips"]
r = obj.fn(1, 3)
self.assertEqual(r.result, ["chips"])
obj.mock.assert_called_once_with(1, 3)
obj.mock.reset_mock()
# the two values should now be cached
self.assertEqual(len(obj.fn.cache.cache), 3)
r = obj.fn(1, 2)
self.assertEqual(r.result, ["spam", "eggs"])
r = obj.fn(1, 3)
self.assertEqual(r.result, ["chips"])
obj.mock.assert_not_called()
def test_cache_iterable_with_sync_exception(self):
"""If the wrapped function throws synchronously, things should continue to work"""
class Cls:
@descriptors.cached(iterable=True)
def fn(self, arg1):
raise SynapseError(100, "mai spoon iz too big!!1")
obj = Cls()
# this should fail immediately
d = obj.fn(1)
self.failureResultOf(d, SynapseError)
# ... leaving the cache empty
self.assertEqual(len(obj.fn.cache.cache), 0)
# and a second call should result in a second exception
d = obj.fn(1)
self.failureResultOf(d, SynapseError)
def test_invalidate_cascade(self):
"""Invalidations should cascade up through cache contexts"""
class Cls:
@cached(cache_context=True)
async def func1(self, key, cache_context):
return await self.func2(key, on_invalidate=cache_context.invalidate)
@cached(cache_context=True)
async def func2(self, key, cache_context):
return self.func3(key, on_invalidate=cache_context.invalidate)
@lru_cache(cache_context=True)
def func3(self, key, cache_context):
self.invalidate = cache_context.invalidate
return 42
obj = Cls()
top_invalidate = mock.Mock()
r = get_awaitable_result(obj.func1("k1", on_invalidate=top_invalidate))
self.assertEqual(r, 42)
obj.invalidate()
top_invalidate.assert_called_once()
def test_cancel(self):
"""Test that cancelling a lookup does not cancel other lookups"""
complete_lookup: "Deferred[None]" = Deferred()
class Cls:
@cached()
async def fn(self, arg1):
await complete_lookup
return str(arg1)
obj = Cls()
d1 = obj.fn(123)
d2 = obj.fn(123)
self.assertFalse(d1.called)
self.assertFalse(d2.called)
# Cancel `d1`, which is the lookup that caused `fn` to run.
d1.cancel()
# `d2` should complete normally.
complete_lookup.callback(None)
self.failureResultOf(d1, CancelledError)
self.assertEqual(d2.result, "123")
def test_cancel_logcontexts(self):
"""Test that cancellation does not break logcontexts.
* The `CancelledError` must be raised with the correct logcontext.
* The inner lookup must not resume with a finished logcontext.
* The inner lookup must not restore a finished logcontext when done.
"""
complete_lookup: "Deferred[None]" = Deferred()
class Cls:
inner_context_was_finished = False
@cached()
async def fn(self, arg1):
await make_deferred_yieldable(complete_lookup)
self.inner_context_was_finished = current_context().finished
return str(arg1)
obj = Cls()
async def do_lookup():
with LoggingContext("c1") as c1:
try:
await obj.fn(123)
self.fail("No CancelledError thrown")
except CancelledError:
self.assertEqual(
current_context(),
c1,
"CancelledError was not raised with the correct logcontext",
)
# suppress the error and succeed
d = defer.ensureDeferred(do_lookup())
d.cancel()
complete_lookup.callback(None)
self.successResultOf(d)
self.assertFalse(
obj.inner_context_was_finished, "Tried to restart a finished logcontext"
)
self.assertEqual(current_context(), SENTINEL_CONTEXT)
class CacheDecoratorTestCase(unittest.HomeserverTestCase):
"""More tests for @cached
The following is a set of tests that got lost in a different file for a while.
There are probably duplicates of the tests in DescriptorTestCase. Ideally the
duplicates would be removed and the two sets of classes combined.
"""
@defer.inlineCallbacks
def test_passthrough(self):
class A:
@cached()
def func(self, key):
return key
a = A()
self.assertEqual((yield a.func("foo")), "foo")
self.assertEqual((yield a.func("bar")), "bar")
@defer.inlineCallbacks
def test_hit(self):
callcount = [0]
class A:
@cached()
def func(self, key):
callcount[0] += 1
return key
a = A()
yield a.func("foo")
self.assertEqual(callcount[0], 1)
self.assertEqual((yield a.func("foo")), "foo")
self.assertEqual(callcount[0], 1)
@defer.inlineCallbacks
def test_invalidate(self):
callcount = [0]
class A:
@cached()
def func(self, key):
callcount[0] += 1
return key
a = A()
yield a.func("foo")
self.assertEqual(callcount[0], 1)
a.func.invalidate(("foo",))
yield a.func("foo")
self.assertEqual(callcount[0], 2)
def test_invalidate_missing(self):
class A:
@cached()
def func(self, key):
return key
A().func.invalidate(("what",))
@defer.inlineCallbacks
def test_max_entries(self):
callcount = [0]
class A:
@cached(max_entries=10)
def func(self, key):
callcount[0] += 1
return key
a = A()
for k in range(0, 12):
yield a.func(k)
self.assertEqual(callcount[0], 12)
# There must have been at least 2 evictions, meaning if we calculate
# all 12 values again, we must get called at least 2 more times
for k in range(0, 12):
yield a.func(k)
self.assertTrue(
callcount[0] >= 14, msg="Expected callcount >= 14, got %d" % (callcount[0])
)
def test_prefill(self):
callcount = [0]
d = defer.succeed(123)
class A:
@cached()
def func(self, key):
callcount[0] += 1
return d
a = A()
a.func.prefill(("foo",), 456)
self.assertEqual(a.func("foo").result, 456)
self.assertEqual(callcount[0], 0)
@defer.inlineCallbacks
def test_invalidate_context(self):
callcount = [0]
callcount2 = [0]
class A:
@cached()
def func(self, key):
callcount[0] += 1
return key
@cached(cache_context=True)
def func2(self, key, cache_context):
callcount2[0] += 1
return self.func(key, on_invalidate=cache_context.invalidate)
a = A()
yield a.func2("foo")
self.assertEqual(callcount[0], 1)
self.assertEqual(callcount2[0], 1)
a.func.invalidate(("foo",))
yield a.func("foo")
self.assertEqual(callcount[0], 2)
self.assertEqual(callcount2[0], 1)
yield a.func2("foo")
self.assertEqual(callcount[0], 2)
self.assertEqual(callcount2[0], 2)
@defer.inlineCallbacks
def test_eviction_context(self):
callcount = [0]
callcount2 = [0]
class A:
@cached(max_entries=2)
def func(self, key):
callcount[0] += 1
return key
@cached(cache_context=True)
def func2(self, key, cache_context):
callcount2[0] += 1
return self.func(key, on_invalidate=cache_context.invalidate)
a = A()
yield a.func2("foo")
yield a.func2("foo2")
self.assertEqual(callcount[0], 2)
self.assertEqual(callcount2[0], 2)
yield a.func2("foo")
self.assertEqual(callcount[0], 2)
self.assertEqual(callcount2[0], 2)
yield a.func("foo3")
self.assertEqual(callcount[0], 3)
self.assertEqual(callcount2[0], 2)
yield a.func2("foo")
self.assertEqual(callcount[0], 4)
self.assertEqual(callcount2[0], 3)
@defer.inlineCallbacks
def test_double_get(self):
callcount = [0]
callcount2 = [0]
class A:
@cached()
def func(self, key):
callcount[0] += 1
return key
@cached(cache_context=True)
def func2(self, key, cache_context):
callcount2[0] += 1
return self.func(key, on_invalidate=cache_context.invalidate)
a = A()
a.func2.cache.cache = mock.Mock(wraps=a.func2.cache.cache)
yield a.func2("foo")
self.assertEqual(callcount[0], 1)
self.assertEqual(callcount2[0], 1)
a.func2.invalidate(("foo",))
self.assertEqual(a.func2.cache.cache.del_multi.call_count, 1)
yield a.func2("foo")
a.func2.invalidate(("foo",))
self.assertEqual(a.func2.cache.cache.del_multi.call_count, 2)
self.assertEqual(callcount[0], 1)
self.assertEqual(callcount2[0], 2)
a.func.invalidate(("foo",))
self.assertEqual(a.func2.cache.cache.del_multi.call_count, 3)
yield a.func("foo")
self.assertEqual(callcount[0], 2)
self.assertEqual(callcount2[0], 2)
yield a.func2("foo")
self.assertEqual(callcount[0], 2)
self.assertEqual(callcount2[0], 3)
class CachedListDescriptorTestCase(unittest.TestCase):
@defer.inlineCallbacks
def test_cache(self):
class Cls:
def __init__(self):
self.mock = mock.Mock()
@descriptors.cached()
def fn(self, arg1, arg2):
pass
@descriptors.cachedList(cached_method_name="fn", list_name="args1")
async def list_fn(self, args1, arg2):
assert current_context().name == "c1"
# we want this to behave like an asynchronous function
await run_on_reactor()
assert current_context().name == "c1"
return self.mock(args1, arg2)
with LoggingContext("c1") as c1:
obj = Cls()
obj.mock.return_value = {10: "fish", 20: "chips"}
# start the lookup off
d1 = obj.list_fn([10, 20], 2)
self.assertEqual(current_context(), SENTINEL_CONTEXT)
r = yield d1
self.assertEqual(current_context(), c1)
obj.mock.assert_called_once_with({10, 20}, 2)
self.assertEqual(r, {10: "fish", 20: "chips"})
obj.mock.reset_mock()
# a call with different params should call the mock again
obj.mock.return_value = {30: "peas"}
r = yield obj.list_fn([20, 30], 2)
obj.mock.assert_called_once_with({30}, 2)
self.assertEqual(r, {20: "chips", 30: "peas"})
obj.mock.reset_mock()
# all the values should now be cached
r = yield obj.fn(10, 2)
self.assertEqual(r, "fish")
r = yield obj.fn(20, 2)
self.assertEqual(r, "chips")
r = yield obj.fn(30, 2)
self.assertEqual(r, "peas")
r = yield obj.list_fn([10, 20, 30], 2)
obj.mock.assert_not_called()
self.assertEqual(r, {10: "fish", 20: "chips", 30: "peas"})
# we should also be able to use a (single-use) iterable, and should
# deduplicate the keys
obj.mock.reset_mock()
obj.mock.return_value = {40: "gravy"}
iterable = (x for x in [10, 40, 40])
r = yield obj.list_fn(iterable, 2)
obj.mock.assert_called_once_with({40}, 2)
self.assertEqual(r, {10: "fish", 40: "gravy"})
def test_concurrent_lookups(self):
"""All concurrent lookups should get the same result"""
class Cls:
def __init__(self):
self.mock = mock.Mock()
@descriptors.cached()
def fn(self, arg1):
pass
@descriptors.cachedList(cached_method_name="fn", list_name="args1")
def list_fn(self, args1) -> "Deferred[dict]":
return self.mock(args1)
obj = Cls()
deferred_result = Deferred()
obj.mock.return_value = deferred_result
# start off several concurrent lookups of the same key
d1 = obj.list_fn([10])
d2 = obj.list_fn([10])
d3 = obj.list_fn([10])
# the mock should have been called exactly once
obj.mock.assert_called_once_with({10})
obj.mock.reset_mock()
# ... and none of the calls should yet be complete
self.assertFalse(d1.called)
self.assertFalse(d2.called)
self.assertFalse(d3.called)
# complete the lookup. @cachedList functions need to complete with a map
# of input->result
deferred_result.callback({10: "peas"})
# ... which should give the right result to all the callers
self.assertEqual(self.successResultOf(d1), {10: "peas"})
self.assertEqual(self.successResultOf(d2), {10: "peas"})
self.assertEqual(self.successResultOf(d3), {10: "peas"})
@defer.inlineCallbacks
def test_invalidate(self):
"""Make sure that invalidation callbacks are called."""
class Cls:
def __init__(self):
self.mock = mock.Mock()
@descriptors.cached()
def fn(self, arg1, arg2):
pass
@descriptors.cachedList(cached_method_name="fn", list_name="args1")
async def list_fn(self, args1, arg2):
# we want this to behave like an asynchronous function
await run_on_reactor()
return self.mock(args1, arg2)
obj = Cls()
invalidate0 = mock.Mock()
invalidate1 = mock.Mock()
# cache miss
obj.mock.return_value = {10: "fish", 20: "chips"}
r1 = yield obj.list_fn([10, 20], 2, on_invalidate=invalidate0)
obj.mock.assert_called_once_with({10, 20}, 2)
self.assertEqual(r1, {10: "fish", 20: "chips"})
obj.mock.reset_mock()
# cache hit
r2 = yield obj.list_fn([10, 20], 2, on_invalidate=invalidate1)
obj.mock.assert_not_called()
self.assertEqual(r2, {10: "fish", 20: "chips"})
invalidate0.assert_not_called()
invalidate1.assert_not_called()
# now if we invalidate the keys, both invalidations should get called
obj.fn.invalidate((10, 2))
invalidate0.assert_called_once()
invalidate1.assert_called_once()
def test_cancel(self):
"""Test that cancelling a lookup does not cancel other lookups"""
complete_lookup: "Deferred[None]" = Deferred()
class Cls:
@cached()
def fn(self, arg1):
pass
@cachedList(cached_method_name="fn", list_name="args")
async def list_fn(self, args):
await complete_lookup
return {arg: str(arg) for arg in args}
obj = Cls()
d1 = obj.list_fn([123, 456])
d2 = obj.list_fn([123, 456, 789])
self.assertFalse(d1.called)
self.assertFalse(d2.called)
d1.cancel()
# `d2` should complete normally.
complete_lookup.callback(None)
self.failureResultOf(d1, CancelledError)
self.assertEqual(d2.result, {123: "123", 456: "456", 789: "789"})
def test_cancel_logcontexts(self):
"""Test that cancellation does not break logcontexts.
* The `CancelledError` must be raised with the correct logcontext.
* The inner lookup must not resume with a finished logcontext.
* The inner lookup must not restore a finished logcontext when done.
"""
complete_lookup: "Deferred[None]" = Deferred()
class Cls:
inner_context_was_finished = False
@cached()
def fn(self, arg1):
pass
@cachedList(cached_method_name="fn", list_name="args")
async def list_fn(self, args):
await make_deferred_yieldable(complete_lookup)
self.inner_context_was_finished = current_context().finished
return {arg: str(arg) for arg in args}
obj = Cls()
async def do_lookup():
with LoggingContext("c1") as c1:
try:
await obj.list_fn([123])
self.fail("No CancelledError thrown")
except CancelledError:
self.assertEqual(
current_context(),
c1,
"CancelledError was not raised with the correct logcontext",
)
# suppress the error and succeed
d = defer.ensureDeferred(do_lookup())
d.cancel()
complete_lookup.callback(None)
self.successResultOf(d)
self.assertFalse(
obj.inner_context_was_finished, "Tried to restart a finished logcontext"
)
self.assertEqual(current_context(), SENTINEL_CONTEXT)