Fix KeystoneMiddleware memcachepool abstraction

Keystonemiddleware's abstraction for the memcache pool was broken
when converting to use a queue.Queue. The logic that placed the
connection back into the pool was moved to .acquire and the reserve
method was not using acquire.

Change-Id: I0eda5981cbb661f63790258cf8e70c7340615159
Closes-Bug: #1782404
This commit is contained in:
Morgan Fainberg 2018-07-18 11:26:18 -07:00
parent d1b7a1f092
commit c46f29278d
3 changed files with 36 additions and 1 deletions

View File

@ -98,7 +98,11 @@ class _MemcacheClientPool(object):
@contextlib.contextmanager
def reserve(self):
yield self._pool.get()
# NOTE(morgan): We must use "acquire" if we want all the added context
# manager logic that places the connection back into the pool at the
# end of it's use.
with self._pool.acquire() as client:
yield client
class TokenCache(object):

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@ -12,8 +12,10 @@
import uuid
import fixtures
import six
from keystonemiddleware.auth_token import _cache
from keystonemiddleware.auth_token import _exceptions as exc
from keystonemiddleware.tests.unit.auth_token import base
from keystonemiddleware.tests.unit import utils
@ -165,3 +167,24 @@ class TestLiveMemcache(base.BaseAuthTokenTestCase):
token_cache.set(token, data)
self.assertEqual(token_cache.get(token), data)
class TestMemcachePoolAbstraction(utils.TestCase):
def setUp(self):
super(TestMemcachePoolAbstraction, self).setUp()
self.useFixture(fixtures.MockPatch(
'oslo_cache._memcache_pool._MemcacheClient'))
def test_abstraction_layer_reserve_places_connection_back_in_pool(self):
cache_pool = _cache._MemcacheClientPool(
memcache_servers=[], arguments={}, maxsize=1, unused_timeout=10)
conn = None
with cache_pool.reserve() as client:
self.assertEqual(cache_pool._pool._acquired, 1)
conn = client
self.assertEqual(cache_pool._pool._acquired, 0)
with cache_pool.reserve() as client:
# Make sure the connection we got before is in-fact the one we
# get again.
self.assertEqual(conn, client)

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@ -0,0 +1,8 @@
---
fixes:
- >
[`bug 1782404 <https://bugs.launchpad.net/keystonemiddleware/+bug/1782404>`_]
Keystonemiddleware incorrectly implemented an abstraction for the memcache
client pool that utilized a `queue.Queue` `get` method instead of the
supplied `acquire()` context manager. The `acquire()` context manager
properly places the client connection back into the pool after `__exit__`.