zuul/zuul/zk/config_cache.py
Clark Boylan 21ccbe8ba2 Unvendor kazoo locks recipes
These recipes were vendored so that we could carry this fix locally:
  https://github.com/python-zk/kazoo/pull/650

It appears that this fix has been merged and included in kazoo>=2.9.0 so
we include that as the minimum version and drop the vendored file.

This also fixes the isSet() deprecation warning as upstream kazoo has
switched to is_set().

Change-Id: Ide48e9f949e083b658775b74db3856b118fc5d69
2023-01-11 11:16:34 -08:00

242 lines
8.2 KiB
Python

# Copyright 2021 BMW Group
#
# 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 contextlib
import json
import logging
from collections.abc import MutableMapping
from urllib.parse import quote_plus, unquote_plus
from kazoo.exceptions import NoNodeError
from kazoo.recipe import lock
from zuul import model
from zuul.zk import sharding, ZooKeeperSimpleBase
CONFIG_ROOT = "/zuul/config"
def _safe_path(root_path, *keys):
return "/".join((root_path, *(quote_plus(k) for k in keys)))
class FilesCache(ZooKeeperSimpleBase, MutableMapping):
"""Cache of raw config files in Zookeeper for a project-branch.
Data will be stored in Zookeeper using the following path:
/zuul/config/<project>/<branch>/<filename>
"""
log = logging.getLogger("zuul.zk.config_cache.FilesCache")
def __init__(self, client, root_path):
super().__init__(client)
self.root_path = root_path
self.files_path = f"{root_path}/files"
def setValidFor(self, extra_config_files, extra_config_dirs, ltime):
"""Set the cache valid for the given extra config files/dirs."""
data = {
"extra_files_searched": list(extra_config_files),
"extra_dirs_searched": list(extra_config_dirs),
"ltime": ltime,
}
payload = json.dumps(data, sort_keys=True).encode("utf8")
try:
self.kazoo_client.set(self.root_path, payload)
except NoNodeError:
self.kazoo_client.create(self.root_path, payload, makepath=True)
def isValidFor(self, tpc, min_ltime):
"""Check if the cache is valid.
Check if the cache is valid for the given tenant project config
(tpc) and that it is up-to-date, relative to the give logical
timestamp.
"""
try:
data, _ = self.kazoo_client.get(self.root_path)
except NoNodeError:
return False
try:
content = json.loads(data)
extra_files_searched = set(content["extra_files_searched"])
extra_dirs_searched = set(content["extra_dirs_searched"])
ltime = content["ltime"]
except Exception:
return False
if ltime < min_ltime:
# Cache is outdated
return False
return (set(tpc.extra_config_files) <= extra_files_searched
and set(tpc.extra_config_dirs) <= extra_dirs_searched)
@property
def ltime(self):
try:
data, _ = self.kazoo_client.get(self.root_path)
content = json.loads(data)
return content["ltime"]
except Exception:
return -1
def _key_path(self, key):
return _safe_path(self.files_path, key)
def __getitem__(self, key):
try:
with sharding.BufferedShardReader(
self.kazoo_client, self._key_path(key)
) as stream:
return stream.read().decode("utf8")
except NoNodeError:
raise KeyError(key)
def __setitem__(self, key, value):
path = self._key_path(key)
with sharding.BufferedShardWriter(self.kazoo_client, path) as stream:
stream.truncate(0)
stream.write(value.encode("utf8"))
def __delitem__(self, key):
try:
self.kazoo_client.delete(self._key_path(key), recursive=True)
except NoNodeError:
raise KeyError(key)
def __iter__(self):
try:
children = self.kazoo_client.get_children(self.files_path)
except NoNodeError:
children = []
yield from sorted(unquote_plus(c) for c in children)
def __len__(self):
try:
children = self.kazoo_client.get_children(self.files_path)
except NoNodeError:
children = []
return len(children)
def clear(self):
with contextlib.suppress(NoNodeError):
self.kazoo_client.delete(self.root_path, recursive=True)
class UnparsedConfigCache(ZooKeeperSimpleBase):
"""Zookeeper cache for unparsed config files."""
log = logging.getLogger("zuul.zk.config_cache.UnparsedConfigCache")
def __init__(self, client, config_root=CONFIG_ROOT):
super().__init__(client)
self.cache_path = f"{config_root}/cache"
self.lock_path = f"{config_root}/lock"
def readLock(self, project_cname):
return lock.ReadLock(
self.kazoo_client, _safe_path(self.lock_path, project_cname))
def writeLock(self, project_cname):
return lock.WriteLock(
self.kazoo_client, _safe_path(self.lock_path, project_cname))
def getFilesCache(self, project_cname, branch_name):
path = _safe_path(self.cache_path, project_cname, branch_name)
return FilesCache(self.client, path)
def listCachedProjects(self):
try:
children = self.kazoo_client.get_children(self.cache_path)
except NoNodeError:
children = []
yield from sorted(unquote_plus(c) for c in children)
def clearCache(self, project_cname, branch_name=None):
if branch_name is None:
path = _safe_path(self.cache_path, project_cname)
else:
path = _safe_path(self.cache_path, project_cname, branch_name)
with contextlib.suppress(NoNodeError):
self.kazoo_client.delete(path, recursive=True)
class SystemConfigCache(ZooKeeperSimpleBase):
"""Zookeeper cache for Zuul system configuration.
The system configuration consists of the unparsed abide config and
the runtime related settings from the Zuul config file.
"""
SYSTEM_ROOT = "/zuul/system"
log = logging.getLogger("zuul.zk.SystemConfigCache")
def __init__(self, client, callback):
super().__init__(client)
self.conf_path = f"{self.SYSTEM_ROOT}/conf"
self.lock_path = f"{self.SYSTEM_ROOT}/conf-lock"
self._callback = callback
self.kazoo_client.DataWatch(self.conf_path, self._configChanged)
def _configChanged(self, data, stat, event):
self._callback()
@property
def ltime(self):
with lock.ReadLock(self.kazoo_client, self.lock_path):
zstat = self.kazoo_client.exists(self.conf_path)
return -1 if zstat is None else zstat.last_modified_transaction_id
@property
def is_valid(self):
return self.ltime > -1
def get(self):
"""Get the system configuration from Zookeeper.
:returns: A tuple (unparsed abide config, system attributes)
"""
with lock.ReadLock(self.kazoo_client, self.lock_path):
try:
with sharding.BufferedShardReader(
self.kazoo_client, self.conf_path
) as stream:
data = json.loads(stream.read())
except Exception:
raise RuntimeError("No valid system config")
zstat = self.kazoo_client.exists(self.conf_path)
return (model.UnparsedAbideConfig.fromDict(
data["unparsed_abide"],
ltime=zstat.last_modified_transaction_id
), model.SystemAttributes.fromDict(data["system_attributes"]))
def set(self, unparsed_abide, system_attributes):
with lock.WriteLock(self.kazoo_client, self.lock_path):
data = {
"unparsed_abide": unparsed_abide.toDict(),
"system_attributes": system_attributes.toDict(),
}
with sharding.BufferedShardWriter(
self.kazoo_client, self.conf_path
) as stream:
stream.truncate(0)
stream.write(json.dumps(data, sort_keys=True).encode("utf8"))
zstat = self.kazoo_client.exists(self.conf_path)
unparsed_abide.ltime = zstat.last_modified_transaction_id