unrhodecode/rhodecode/lib/rc_cache/backends.py
2025-01-13 17:47:37 +01:00

331 lines
11 KiB
Python

# Copyright (C) 2015-2024 RhodeCode GmbH
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License, version 3
# (only), as published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
# This program is dual-licensed. If you wish to learn more about the
# RhodeCode Enterprise Edition, including its added features, Support services,
# and proprietary license terms, please see https://rhodecode.com/licenses/
import errno
import fcntl
import functools
import logging
import os
import pickle
import time
import gevent
import msgpack
import redis
flock_org = fcntl.flock
from typing import Union
from dogpile.cache.api import Deserializer, Serializer
from dogpile.cache.backends import file as file_backend
from dogpile.cache.backends import memory as memory_backend
from dogpile.cache.backends import redis as redis_backend
from dogpile.cache.backends.file import FileLock
from dogpile.cache.util import memoized_property
from ...lib.memory_lru_dict import LRUDict, LRUDictDebug
from ...lib.str_utils import safe_bytes, safe_str
from ...lib.type_utils import str2bool
_default_max_size = 1024
log = logging.getLogger(__name__)
class LRUMemoryBackend(memory_backend.MemoryBackend):
key_prefix = "lru_mem_backend"
pickle_values = False
def __init__(self, arguments):
self.max_size = arguments.pop("max_size", _default_max_size)
LRUDictClass = LRUDict
if arguments.pop("log_key_count", None):
LRUDictClass = LRUDictDebug
arguments["cache_dict"] = LRUDictClass(self.max_size)
super().__init__(arguments)
def __repr__(self):
return f"{self.__class__}(maxsize=`{self.max_size}`)"
def __str__(self):
return self.__repr__()
def delete(self, key):
try:
del self._cache[key]
except KeyError:
# we don't care if key isn't there at deletion
pass
def list_keys(self, prefix):
return list(self._cache.keys())
def delete_multi(self, keys):
for key in keys:
self.delete(key)
def delete_multi_by_prefix(self, prefix):
cache_keys = self.list_keys(prefix=prefix)
num_affected_keys = len(cache_keys)
if num_affected_keys:
self.delete_multi(cache_keys)
return num_affected_keys
class PickleSerializer:
serializer: None | Serializer = staticmethod( # type: ignore
functools.partial(pickle.dumps, protocol=pickle.HIGHEST_PROTOCOL)
)
deserializer: None | Deserializer = staticmethod( # type: ignore
functools.partial(pickle.loads)
)
class MsgPackSerializer:
serializer: None | Serializer = staticmethod( # type: ignore
msgpack.packb
)
deserializer: None | Deserializer = staticmethod( # type: ignore
functools.partial(msgpack.unpackb, use_list=False)
)
class CustomLockFactory(FileLock):
@memoized_property
def _module(self):
def gevent_flock(fd, operation):
"""
Gevent compatible flock
"""
# set non-blocking, this will cause an exception if we cannot acquire a lock
operation |= fcntl.LOCK_NB
start_lock_time = time.time()
timeout = 60 * 15 # 15min
while True:
try:
flock_org(fd, operation)
# lock has been acquired
break
except (OSError, IOError) as e:
# raise on other errors than Resource temporarily unavailable
if e.errno != errno.EAGAIN:
raise
elif (time.time() - start_lock_time) > timeout:
# waited to much time on a lock, better fail than loop for ever
log.error("Failed to acquire lock on `%s` after waiting %ss", self.filename, timeout)
raise
wait_timeout = 0.03
log.debug("Failed to acquire lock on `%s`, retry in %ss", self.filename, wait_timeout)
gevent.sleep(wait_timeout)
fcntl.flock = gevent_flock
return fcntl
class FileNamespaceBackend(PickleSerializer, file_backend.DBMBackend):
key_prefix = "file_backend"
def __init__(self, arguments):
arguments["lock_factory"] = CustomLockFactory
db_file = arguments.get("filename")
log.debug("initialing cache-backend=%s db in %s", self.__class__.__name__, db_file)
db_file_dir = os.path.dirname(db_file)
if not os.path.isdir(db_file_dir):
os.makedirs(db_file_dir)
try:
super().__init__(arguments)
except Exception:
log.exception("Failed to initialize db at: %s", db_file)
raise
def __repr__(self):
return f"{self.__class__}(file=`{self.filename}`)"
def __str__(self):
return self.__repr__()
def _get_keys_pattern(self, prefix: bytes = b""):
return b"%b:%b" % (safe_bytes(self.key_prefix), safe_bytes(prefix))
def list_keys(self, prefix: bytes = b""):
prefix = self._get_keys_pattern(prefix)
def cond(dbm_key: bytes):
if not prefix:
return True
if dbm_key.startswith(prefix):
return True
return False
with self._dbm_file(True) as dbm:
try:
return list(filter(cond, dbm.keys()))
except Exception:
log.error("Failed to fetch DBM keys from DB: %s", self.get_store())
raise
def delete_multi_by_prefix(self, prefix):
cache_keys = self.list_keys(prefix=prefix)
num_affected_keys = len(cache_keys)
if num_affected_keys:
self.delete_multi(cache_keys)
return num_affected_keys
def get_store(self):
return self.filename
def cleanup_store(self):
for ext in ("db", "dat", "pag", "dir"):
final_filename = self.filename + os.extsep + ext
if os.path.exists(final_filename):
os.remove(final_filename)
log.warning("Removed dbm file %s", final_filename)
class BaseRedisBackend(redis_backend.RedisBackend):
key_prefix = ""
def __init__(self, arguments):
self.db_conn = arguments.get("host", "") or arguments.get("url", "") or "redis-host"
super().__init__(arguments)
self._lock_timeout = self.lock_timeout
self._lock_auto_renewal = str2bool(arguments.pop("lock_auto_renewal", True))
self._store_key_prefix = arguments.pop("key_prefix", "")
self.key_prefix = f"{self._store_key_prefix}{self.key_prefix}"
if self._lock_auto_renewal and not self._lock_timeout:
# set default timeout for auto_renewal
self._lock_timeout = 30
def __repr__(self):
return f"{self.__class__}(conn=`{self.db_conn}`)"
def __str__(self):
return self.__repr__()
def _create_client(self):
args = {}
if self.url is not None:
args.update(url=self.url)
else:
args.update(host=self.host, password=self.password, port=self.port, db=self.db)
connection_pool = redis.ConnectionPool(**args)
self.writer_client = redis.StrictRedis(connection_pool=connection_pool)
self.reader_client = self.writer_client
def _get_keys_pattern(self, prefix: bytes = b""):
return b"%b:%b*" % (safe_bytes(self.key_prefix), safe_bytes(prefix))
def list_keys(self, prefix: bytes = b""):
prefix = self._get_keys_pattern(prefix)
return self.reader_client.keys(prefix)
def delete_multi_by_prefix(self, prefix, use_lua=False):
if use_lua:
# high efficient LUA script to delete ALL keys by prefix...
lua = """local keys = redis.call('keys', ARGV[1])
for i=1,#keys,5000 do
redis.call('del', unpack(keys, i, math.min(i+(5000-1), #keys)))
end
return #keys"""
num_affected_keys = self.writer_client.eval(lua, 0, f"{prefix}*")
else:
cache_keys = self.list_keys(prefix=prefix)
num_affected_keys = len(cache_keys)
if num_affected_keys:
self.delete_multi(cache_keys)
return num_affected_keys
def get_store(self):
return self.reader_client.connection_pool
def get_mutex(self, key):
if self.distributed_lock:
lock_key = f"{self._store_key_prefix}_lock_{safe_str(key)}"
return get_mutex_lock(
self.writer_client, lock_key, self._lock_timeout, auto_renewal=self._lock_auto_renewal
)
else:
return None
class RedisPickleBackend(PickleSerializer, BaseRedisBackend):
key_prefix = "redis_pickle_backend"
pass
class RedisMsgPackBackend(MsgPackSerializer, BaseRedisBackend):
key_prefix = "redis_msgpack_backend"
pass
def get_mutex_lock(client, lock_key, lock_timeout, auto_renewal=False):
from ...lib._vendor import redis_lock
class _RedisLockWrapper:
"""LockWrapper for redis_lock"""
@classmethod
def get_lock(cls):
return redis_lock.Lock(
redis_client=client,
name=lock_key,
expire=lock_timeout,
auto_renewal=auto_renewal,
strict=True,
)
def __repr__(self):
return f"{self.__class__.__name__}:{lock_key}"
def __str__(self):
return f"{self.__class__.__name__}:{lock_key}"
def __init__(self):
self.lock = self.get_lock()
self.lock_key = lock_key
def acquire(self, wait=True):
log.debug("Trying to acquire Redis lock for key %s", self.lock_key)
try:
acquired = self.lock.acquire(wait)
log.debug("Got lock for key %s, %s", self.lock_key, acquired)
return acquired
except redis_lock.AlreadyAcquired:
return False
except redis_lock.AlreadyStarted:
# refresh thread exists, but it also means we acquired the lock
return True
def release(self):
try:
self.lock.release()
except redis_lock.NotAcquired:
pass
return _RedisLockWrapper()