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author | 2017-11-24 13:54:26 +0100 | |
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committer | 2017-11-24 13:54:26 +0100 | |
commit | 920a49cfa055733d575282973e23558c33087a4a (patch) | |
tree | d371dab34efa5028600dad2e7ca58063626e7ba4 /keystone-moon/keystone/common/kvs/backends/memcached.py | |
parent | ef3eefca70d8abb4a00dafb9419ad32738e934b2 (diff) |
remove keystone-moon
Change-Id: I80d7c9b669f19d5f6607e162de8e0e55c2f80fdd
Signed-off-by: RHE <rebirthmonkey@gmail.com>
Diffstat (limited to 'keystone-moon/keystone/common/kvs/backends/memcached.py')
-rw-r--r-- | keystone-moon/keystone/common/kvs/backends/memcached.py | 195 |
1 files changed, 0 insertions, 195 deletions
diff --git a/keystone-moon/keystone/common/kvs/backends/memcached.py b/keystone-moon/keystone/common/kvs/backends/memcached.py deleted file mode 100644 index a65cf877..00000000 --- a/keystone-moon/keystone/common/kvs/backends/memcached.py +++ /dev/null @@ -1,195 +0,0 @@ -# Copyright 2013 Metacloud, Inc. -# -# 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. - -"""Keystone Memcached dogpile.cache backend implementation.""" - -import random as _random -import time - -from dogpile.cache import api -from dogpile.cache.backends import memcached -from oslo_cache.backends import memcache_pool -from oslo_config import cfg -from six.moves import range - -from keystone import exception -from keystone.i18n import _ - - -CONF = cfg.CONF -NO_VALUE = api.NO_VALUE -random = _random.SystemRandom() - -VALID_DOGPILE_BACKENDS = dict( - pylibmc=memcached.PylibmcBackend, - bmemcached=memcached.BMemcachedBackend, - memcached=memcached.MemcachedBackend, - pooled_memcached=memcache_pool.PooledMemcachedBackend) - - -class MemcachedLock(object): - """Simple distributed lock using memcached. - - This is an adaptation of the lock featured at - http://amix.dk/blog/post/19386 - - """ - - def __init__(self, client_fn, key, lock_timeout, max_lock_attempts): - self.client_fn = client_fn - self.key = "_lock" + key - self.lock_timeout = lock_timeout - self.max_lock_attempts = max_lock_attempts - - def acquire(self, wait=True): - client = self.client_fn() - for i in range(self.max_lock_attempts): - if client.add(self.key, 1, self.lock_timeout): - return True - elif not wait: - return False - else: - sleep_time = random.random() # nosec : random is not used for - # crypto or security, it's just the time to delay between - # retries. - time.sleep(sleep_time) - raise exception.UnexpectedError( - _('Maximum lock attempts on %s occurred.') % self.key) - - def release(self): - client = self.client_fn() - client.delete(self.key) - - -class MemcachedBackend(object): - """Pivot point to leverage the various dogpile.cache memcached backends. - - To specify a specific dogpile.cache memcached backend, pass the argument - `memcached_backend` set to one of the provided memcached backends (at this - time `memcached`, `bmemcached`, `pylibmc` and `pooled_memcached` are - valid). - """ - - def __init__(self, arguments): - self._key_mangler = None - self.raw_no_expiry_keys = set(arguments.pop('no_expiry_keys', set())) - self.no_expiry_hashed_keys = set() - - self.lock_timeout = arguments.pop('lock_timeout', None) - self.max_lock_attempts = arguments.pop('max_lock_attempts', 15) - # NOTE(morganfainberg): Remove distributed locking from the arguments - # passed to the "real" backend if it exists. - arguments.pop('distributed_lock', None) - backend = arguments.pop('memcached_backend', None) - if 'url' not in arguments: - # FIXME(morganfainberg): Log deprecation warning for old-style - # configuration once full dict_config style configuration for - # KVS backends is supported. For now use the current memcache - # section of the configuration. - arguments['url'] = CONF.memcache.servers - - if backend is None: - # NOTE(morganfainberg): Use the basic memcached backend if nothing - # else is supplied. - self.driver = VALID_DOGPILE_BACKENDS['memcached'](arguments) - else: - if backend not in VALID_DOGPILE_BACKENDS: - raise ValueError( - _('Backend `%(backend)s` is not a valid memcached ' - 'backend. Valid backends: %(backend_list)s') % - {'backend': backend, - 'backend_list': ','.join(VALID_DOGPILE_BACKENDS.keys())}) - else: - self.driver = VALID_DOGPILE_BACKENDS[backend](arguments) - - def __getattr__(self, name): - """Forward calls to the underlying driver.""" - f = getattr(self.driver, name) - setattr(self, name, f) - return f - - def _get_set_arguments_driver_attr(self, exclude_expiry=False): - - # NOTE(morganfainberg): Shallow copy the .set_arguments dict to - # ensure no changes cause the values to change in the instance - # variable. - set_arguments = getattr(self.driver, 'set_arguments', {}).copy() - - if exclude_expiry: - # NOTE(morganfainberg): Explicitly strip out the 'time' key/value - # from the set_arguments in the case that this key isn't meant - # to expire - set_arguments.pop('time', None) - return set_arguments - - def set(self, key, value): - mapping = {key: value} - self.set_multi(mapping) - - def set_multi(self, mapping): - mapping_keys = set(mapping.keys()) - no_expiry_keys = mapping_keys.intersection(self.no_expiry_hashed_keys) - has_expiry_keys = mapping_keys.difference(self.no_expiry_hashed_keys) - - if no_expiry_keys: - # NOTE(morganfainberg): For keys that have expiry excluded, - # bypass the backend and directly call the client. Bypass directly - # to the client is required as the 'set_arguments' are applied to - # all ``set`` and ``set_multi`` calls by the driver, by calling - # the client directly it is possible to exclude the ``time`` - # argument to the memcached server. - new_mapping = {k: mapping[k] for k in no_expiry_keys} - set_arguments = self._get_set_arguments_driver_attr( - exclude_expiry=True) - self.driver.client.set_multi(new_mapping, **set_arguments) - - if has_expiry_keys: - new_mapping = {k: mapping[k] for k in has_expiry_keys} - self.driver.set_multi(new_mapping) - - @classmethod - def from_config_dict(cls, config_dict, prefix): - prefix_len = len(prefix) - return cls( - {key[prefix_len:]: config_dict[key] for key in config_dict - if key.startswith(prefix)}) - - @property - def key_mangler(self): - if self._key_mangler is None: - self._key_mangler = self.driver.key_mangler - return self._key_mangler - - @key_mangler.setter - def key_mangler(self, key_mangler): - if callable(key_mangler): - self._key_mangler = key_mangler - self._rehash_keys() - elif key_mangler is None: - # NOTE(morganfainberg): Set the hashed key map to the unhashed - # list since we no longer have a key_mangler. - self._key_mangler = None - self.no_expiry_hashed_keys = self.raw_no_expiry_keys - else: - raise TypeError(_('`key_mangler` functions must be callable.')) - - def _rehash_keys(self): - no_expire = set() - for key in self.raw_no_expiry_keys: - no_expire.add(self._key_mangler(key)) - self.no_expiry_hashed_keys = no_expire - - def get_mutex(self, key): - return MemcachedLock(lambda: self.driver.client, key, - self.lock_timeout, self.max_lock_attempts) |