deb-murano/murano/engine/system/metadef_browser.py
Alexander Tivelkov 343f8b49e3 Murano bindings to Glance Metadef API
Added a python-backed class io.murano.system.MetadefBrowser providing
a read-only access to Glance Metadefinition Catalog. The class can
fetch namespaces mapped to a particular resource type and the contents
(objects) of a given namespace. Since the catalog is not updated
frequently the class provides caching capabilities for the fetched
data.

The MuranoPL part of the class provides a single method called
canBeAppliedTo which may be used to check whether some tag can be
applied to a particular type of resource.

Since Glance connectivity is required, a new configuration section is
added to provide capabilities to tune conection properties (url,
endpoint type, encryption etc).

Change-Id: I8ea70e314dbe701b462fb1620376965af717c10d
Targets-blueprint: meta-attribute-assignment-and-propagation
2016-09-28 20:14:38 +03:00

70 lines
2.4 KiB
Python

# Copyright (c) 2016 Mirantis Inc.
#
# 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 glanceclient.v2.client as gclient
from oslo_config import cfg
from murano.common import auth_utils
from murano.dsl import dsl
from murano.dsl import helpers
from murano.dsl import session_local_storage
CONF = cfg.CONF
@dsl.name('io.murano.system.MetadefBrowser')
class MetadefBrowser(object):
def __init__(self, this, region_name=None, cache=True):
session = helpers.get_execution_session()
self._project_id = session.project_id
self._region = this.find_owner('io.murano.CloudRegion')
self._region_name = region_name
self._cache = cache
self._namespaces = {}
self._objects = {}
@staticmethod
@session_local_storage.execution_session_memoize
def _get_client(region_name):
glance_settings = CONF.glance
return gclient.Client(**auth_utils.get_session_client_parameters(
service_type='image', region=region_name, conf=glance_settings
))
@property
def _client(self):
region = self._region_name or (
None if self._region is None else self._region['name'])
return self._get_client(region)
def get_namespaces(self, resource_type):
if not self._cache or resource_type not in self._namespaces:
nss = list(self._client.metadefs_namespace.list(
resource_type=resource_type))
self._namespaces[resource_type] = nss
return nss
else:
return self._namespaces[resource_type]
def get_objects(self, namespace):
if not self._cache or namespace not in self._objects:
objects = list(self._client.metadefs_object.list(
namespace=namespace))
self._objects[namespace] = objects
return objects
else:
return self._objects[namespace]