kolla/docker/base/set_configs.py
Martin André fc1caced86 Only copy symlinks when merge and preserve_properties are set
The kolla-kubernetes config files live in a ..data directory in the
config volume and are symlinked with relative path at the root of the
config volume. This naturally breaks with the link copy feature
introduce in I92a404b8d301937dc1847d42576e30db43951990.

This commit restores the original behavior to copy the target of the
link unless both 'merge' and 'preserve_properties' options are set, in
which case the link itself is copied.

Change-Id: I5d768687208205fb50ef5ab93675f47e98ea6351
2017-07-17 10:01:38 +02:00

423 lines
14 KiB
Python

#!/usr/bin/env python
# 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 argparse
import glob
import grp
import json
import logging
import os
import pwd
import shutil
import sys
# TODO(rhallisey): add docstring.
logging.basicConfig()
LOG = logging.getLogger(__name__)
LOG.setLevel(logging.INFO)
class ExitingException(Exception):
def __init__(self, message, exit_code=1):
super(ExitingException, self).__init__(message)
self.exit_code = exit_code
class ImmutableConfig(ExitingException):
pass
class InvalidConfig(ExitingException):
pass
class MissingRequiredSource(ExitingException):
pass
class UserNotFound(ExitingException):
pass
class ConfigFileBadState(ExitingException):
pass
class ConfigFile(object):
def __init__(self, source, dest, owner=None, perm=None, optional=False,
preserve_properties=False, merge=False):
self.source = source
self.dest = dest
self.owner = owner
self.perm = perm
self.optional = optional
self.merge = merge
self.preserve_properties = preserve_properties
def __str__(self):
return '<ConfigFile source:"{}" dest:"{}">'.format(self.source,
self.dest)
def _copy_file(self, source, dest):
self._delete_path(dest)
# dest endswith / means copy the <source> to <dest> folder
LOG.info('Copying %s to %s', source, dest)
if self.merge and self.preserve_properties and os.path.islink(source):
link_target = os.readlink(source)
os.symlink(link_target, dest)
else:
shutil.copy(source, dest)
self._set_properties(source, dest)
def _merge_directories(self, source, dest):
if os.path.isdir(source):
if os.path.lexists(dest) and not os.path.isdir(dest):
self._delete_path(dest)
if not os.path.isdir(dest):
LOG.info('Creating directory %s', dest)
os.makedirs(dest)
self._set_properties(source, dest)
dir_content = os.listdir(source)
for to_copy in dir_content:
self._merge_directories(os.path.join(source, to_copy),
os.path.join(dest, to_copy))
else:
self._copy_file(source, dest)
def _delete_path(self, path):
if not os.path.lexists(path):
return
LOG.info('Deleting %s', path)
if os.path.isdir(path):
shutil.rmtree(path)
else:
os.remove(path)
def _create_parent_dirs(self, path):
parent_path = os.path.dirname(path)
if not os.path.exists(parent_path):
os.makedirs(parent_path)
def _set_properties(self, source, dest):
if self.preserve_properties:
self._set_properties_from_file(source, dest)
else:
self._set_properties_from_conf(dest)
def _set_properties_from_file(self, source, dest):
shutil.copystat(source, dest)
stat = os.stat(source)
os.chown(dest, stat.st_uid, stat.st_gid)
def _set_properties_from_conf(self, path):
config = {'permissions':
[{'owner': self.owner, 'path': path, 'perm': self.perm}]}
handle_permissions(config)
def copy(self):
sources = glob.glob(self.source)
if not self.optional and not sources:
raise MissingRequiredSource('%s file is not found' % self.source)
# skip when there is no sources and optional
elif self.optional and not sources:
return
for source in sources:
dest = self.dest
# dest endswith / means copy the <source> into <dest> folder,
# otherwise means copy the source to dest
if dest.endswith(os.sep):
dest = os.path.join(dest, os.path.basename(source))
if not self.merge:
self._delete_path(dest)
self._create_parent_dirs(dest)
self._merge_directories(source, dest)
def _cmp_file(self, source, dest):
# check exsit
if (os.path.exists(source) and
not self.optional and
not os.path.exists(dest)):
return False
# check content
with open(source) as f1, open(dest) as f2:
if f1.read() != f2.read():
LOG.error('The content of source file(%s) and'
' dest file(%s) are not equal.', source, dest)
return False
# check perm
file_stat = os.stat(dest)
actual_perm = oct(file_stat.st_mode)[-4:]
if self.perm != actual_perm:
LOG.error('Dest file does not have expected perm: %s, actual: %s',
self.perm, actual_perm)
return False
# check owner
desired_user, desired_group = user_group(self.owner)
actual_user = pwd.getpwuid(file_stat.st_uid)
if actual_user.pw_name != desired_user:
LOG.error('Dest file does not have expected user: %s,'
' actual: %s ', desired_user, actual_user.pw_name)
return False
actual_group = grp.getgrgid(file_stat.st_gid)
if actual_group.gr_name != desired_group:
LOG.error('Dest file does not have expected group: %s,'
' actual: %s ', desired_group, actual_group.gr_name)
return False
return True
def _cmp_dir(self, source, dest):
for root, dirs, files in os.walk(source):
for dir_ in dirs:
full_path = os.path.join(root, dir_)
dest_full_path = os.path.join(dest, os.path.relpath(source,
full_path))
dir_stat = os.stat(dest_full_path)
actual_perm = oct(dir_stat.st_mode)[-4:]
if self.perm != actual_perm:
LOG.error('Dest dir does not have expected perm: %s,'
' actual %s', self.perm, actual_perm)
return False
for file_ in files:
full_path = os.path.join(root, file_)
dest_full_path = os.path.join(dest, os.path.relpath(source,
full_path))
if not self._cmp_file(full_path, dest_full_path):
return False
return True
def check(self):
bad_state_files = []
sources = glob.glob(self.source)
if not sources and not self.optional:
raise MissingRequiredSource('%s file is not found' % self.source)
elif self.optional and not sources:
return
for source in sources:
dest = self.dest
# dest endswith / means copy the <source> into <dest> folder,
# otherwise means copy the source to dest
if dest.endswith(os.sep):
dest = os.path.join(dest, os.path.basename(source))
if os.path.isdir(source) and not self._cmp_dir(source, dest):
bad_state_files.append(source)
elif not self._cmp_file(source, dest):
bad_state_files.append(source)
if len(bad_state_files) != 0:
msg = 'Following files are in bad state: %s' % bad_state_files
raise ConfigFileBadState(msg)
def validate_config(config):
required_keys = {'source', 'dest'}
if 'command' not in config:
raise InvalidConfig('Config is missing required "command" key')
# Validate config sections
for data in config.get('config_files', list()):
# Verify required keys exist.
if not data.viewkeys() >= required_keys:
message = 'Config is missing required keys: %s' % required_keys
raise InvalidConfig(message)
if ('owner' not in data or 'perm' not in data) \
and not data.get('preserve_properties', False):
raise InvalidConfig(
'Config needs preserve_properties or owner and perm')
def validate_source(data):
source = data.get('source')
# Only check existence if no wildcard found
if '*' not in source:
if not os.path.exists(source):
if data.get('optional'):
LOG.info("%s does not exist, but is not required", source)
return False
else:
raise MissingRequiredSource(
"The source to copy does not exist: %s" % source)
return True
def load_config():
def load_from_env():
config_raw = os.environ.get("KOLLA_CONFIG")
if config_raw is None:
return None
# Attempt to read config
try:
return json.loads(config_raw)
except ValueError:
raise InvalidConfig('Invalid json for Kolla config')
def load_from_file():
config_file = os.environ.get("KOLLA_CONFIG_FILE")
if not config_file:
config_file = '/var/lib/kolla/config_files/config.json'
LOG.info("Loading config file at %s", config_file)
# Attempt to read config file
with open(config_file) as f:
try:
return json.load(f)
except ValueError:
raise InvalidConfig(
"Invalid json file found at %s" % config_file)
except IOError as e:
raise InvalidConfig(
"Could not read file %s: %r" % (config_file, e))
config = load_from_env()
if config is None:
config = load_from_file()
LOG.info('Validating config file')
validate_config(config)
return config
def copy_config(config):
if 'config_files' in config:
LOG.info('Copying service configuration files')
for data in config['config_files']:
config_file = ConfigFile(**data)
config_file.copy()
else:
LOG.debug('No files to copy found in config')
LOG.info('Writing out command to execute')
LOG.debug("Command is: %s", config['command'])
# The value from the 'command' key will be written to '/run_command'
with open('/run_command', 'w+') as f:
f.write(config['command'])
def user_group(owner):
if ':' in owner:
user, group = owner.split(':', 1)
if not group:
group = user
else:
user, group = owner, owner
return user, group
def handle_permissions(config):
for permission in config.get('permissions', list()):
path = permission.get('path')
owner = permission.get('owner')
recurse = permission.get('recurse', False)
perm = permission.get('perm')
desired_user, desired_group = user_group(owner)
uid = pwd.getpwnam(desired_user).pw_uid
gid = grp.getgrnam(desired_group).gr_gid
def set_perms(path, uid, gid, perm):
LOG.info('Setting permission for %s', path)
if not os.path.exists(path):
LOG.warning('%s does not exist', path)
return
try:
os.chown(path, uid, gid)
except OSError:
LOG.exception('Failed to change ownership of %s to %s:%s',
path, uid, gid)
if perm:
# NOTE(Jeffrey4l): py3 need '0oXXX' format for octal literals,
# and py2 support such format too.
if len(perm) == 4 and perm[1] != 'o':
perm = ''.join([perm[:1], 'o', perm[1:]])
perm = int(perm, base=0)
try:
os.chmod(path, perm)
except OSError:
LOG.exception('Failed to set permission of %s to %s',
path, perm)
for dest in glob.glob(path):
set_perms(dest, uid, gid, perm)
if recurse and os.path.isdir(dest):
for root, dirs, files in os.walk(dest):
for dir_ in dirs:
set_perms(os.path.join(root, dir_), uid, gid, perm)
for file_ in files:
set_perms(os.path.join(root, file_), uid, gid, perm)
def execute_config_strategy(config):
config_strategy = os.environ.get("KOLLA_CONFIG_STRATEGY")
LOG.info("Kolla config strategy set to: %s", config_strategy)
if config_strategy == "COPY_ALWAYS":
copy_config(config)
handle_permissions(config)
elif config_strategy == "COPY_ONCE":
if os.path.exists('/configured'):
raise ImmutableConfig(
"The config strategy prevents copying new configs",
exit_code=0)
else:
copy_config(config)
handle_permissions(config)
os.mknod('/configured')
else:
raise InvalidConfig('KOLLA_CONFIG_STRATEGY is not set properly')
def execute_config_check(config):
for data in config['config_files']:
config_file = ConfigFile(**data)
config_file.check()
def main():
try:
parser = argparse.ArgumentParser()
parser.add_argument('--check',
action='store_true',
required=False,
help='Check whether the configs changed')
args = parser.parse_args()
config = load_config()
if args.check:
execute_config_check(config)
else:
execute_config_strategy(config)
except ExitingException as e:
LOG.error("%s: %s", e.__class__.__name__, e)
return e.exit_code
except Exception:
LOG.exception('Unexpected error:')
return 2
return 0
if __name__ == "__main__":
sys.exit(main())