cloudbase-init/cloudbaseinit/plugins/common/userdataplugins/cloudconfig.py

110 lines
3.7 KiB
Python

# Copyright 2013 Mirantis Inc.
# Copyright 2014 Cloudbase Solutions Srl
#
# 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.
from oslo_log import log as oslo_logging
import yaml
from cloudbaseinit import conf as cloudbaseinit_conf
from cloudbaseinit.plugins.common import execcmd
from cloudbaseinit.plugins.common.userdataplugins import base
from cloudbaseinit.plugins.common.userdataplugins.cloudconfigplugins import (
factory
)
CONF = cloudbaseinit_conf.CONF
LOG = oslo_logging.getLogger(__name__)
DEFAULT_ORDER_VALUE = 999
class CloudConfigError(Exception):
pass
class CloudConfigPluginExecutor(object):
"""A simple executor class for processing cloud-config plugins.
:kwarg plugins:
Pairs of plugin names and the values corresponding to that plugin.
"""
def __init__(self, **plugins):
def _lookup_priority(plugin):
try:
return CONF.cloud_config_plugins.index(plugin)
except ValueError:
# If the plugin was not specified in the order
# list, then default to a sane and unreachable value.
return DEFAULT_ORDER_VALUE
self._expected_plugins = sorted(
plugins.items(),
key=lambda item: _lookup_priority(item[0]))
@classmethod
def from_yaml(cls, stream):
"""Initialize an executor from an yaml stream."""
loader = getattr(yaml, 'CLoader', yaml.Loader)
try:
content = yaml.load(stream, Loader=loader)
except (TypeError, ValueError, AttributeError):
raise CloudConfigError("Invalid yaml stream provided.")
if not content:
raise CloudConfigError("Empty yaml stream provided.")
return cls(**content)
def execute(self):
"""Call each plugin, in the order requested by the user."""
reboot = execcmd.NO_REBOOT
plugins = factory.load_plugins()
for plugin_name, value in self._expected_plugins:
method = plugins.get(plugin_name)
if not method:
LOG.error("Plugin %r is currently not supported", plugin_name)
continue
try:
requires_reboot = method(value)
if requires_reboot:
reboot = execcmd.RET_END
except Exception:
LOG.exception("Processing plugin %s failed", plugin_name)
return reboot
class CloudConfigPlugin(base.BaseUserDataPlugin):
def __init__(self):
super(CloudConfigPlugin, self).__init__("text/cloud-config")
def process_non_multipart(self, part):
"""Process the given data, if it can be loaded through yaml.
If any plugin requires a reboot, it will return a particular
value, which will be processed on a higher level.
"""
try:
executor = CloudConfigPluginExecutor.from_yaml(part)
except CloudConfigError as ex:
LOG.error('Could not process part type %(type)r: %(err)r',
{'type': type(part), 'err': str(ex)})
else:
return executor.execute()
def process(self, part):
payload = part.get_payload(decode=True)
return self.process_non_multipart(payload)