kolla/docker/base/set_configs.py
Alex Schultz 2207afc9b9 Add error message when merge fails
If the source cfg directory contains a path (e.g.
/etc/pki/ca-trust/extracted/) which is also bind mounted into the
container as read-only, when it attempts to merge the paths together
the resulting exception doesn't really indicate what happened.

Change-Id: I73bbfd31586012e1fd64d30f9ce1d7eb2256d210
Related-Bug: #1860607
2020-01-24 10:30:03 -07:00

437 lines
15 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)
try:
self._merge_directories(source, dest)
except OSError:
# If a source is tried to merge with a read-only mount, it
# may throw an OSError. Because we don't print the source or
# dest anywhere, let's catch the exception and log a better
# message to help with tracking down the issue.
LOG.error('Unable to merge %s with %s', source, dest)
raise
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 set(data.keys()) >= 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'
cmd = '/run_command'
with open(cmd, 'w+') as f:
f.write(config['command'])
# Make sure the generated file is readable by all users
try:
os.chmod(cmd, 0o644)
except OSError:
LOG.exception('Failed to set permission of %s to 0o644', cmd)
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())