deb-heat/heat/common/identifier.py
Ziad Sawalha c1273677f9 Update common docstrings to match guidelines
Per http://docs.openstack.org/developer/hacking/
and http://www.python.org/dev/peps/pep-0257/

Without extra blank line in multi-line docstrings
based on http://lists.openstack.org/pipermail/openstack-dev/2014-February/028156.html

Blueprint: reduce-flake8-ignored-rules

Change-Id: Ic970fff3b66c357170f45e817d080fdb37c63d6e
2014-05-06 03:40:44 +00:00

237 lines
8.1 KiB
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 collections
import re
from six.moves.urllib import parse as urlparse
from heat.openstack.common import strutils
class HeatIdentifier(collections.Mapping):
FIELDS = (
TENANT, STACK_NAME, STACK_ID, PATH
) = (
'tenant', 'stack_name', 'stack_id', 'path'
)
path_re = re.compile(r'stacks/([^/]+)/([^/]+)(.*)')
def __init__(self, tenant, stack_name, stack_id, path=''):
"""Initialise a HeatIdentifier.
Identifier is initialized from a Tenant ID, Stack name, Stack ID
and optional path. If a path is supplied and it does not begin with
"/", a "/" will be prepended.
"""
if path and not path.startswith('/'):
path = '/' + path
if '/' in stack_name:
raise ValueError(_('Stack name may not contain "/"'))
self.identity = {
self.TENANT: tenant,
self.STACK_NAME: stack_name,
self.STACK_ID: str(stack_id),
self.PATH: path,
}
@classmethod
def from_arn(cls, arn):
"""Generate a new HeatIdentifier by parsing the supplied ARN."""
fields = arn.split(':')
if len(fields) < 6 or fields[0].lower() != 'arn':
raise ValueError(_('"%s" is not a valid ARN') % arn)
id_fragment = ':'.join(fields[5:])
path = cls.path_re.match(id_fragment)
if fields[1] != 'openstack' or fields[2] != 'heat' or not path:
raise ValueError(_('"%s" is not a valid Heat ARN') % arn)
return cls(urlparse.unquote(fields[4]),
urlparse.unquote(path.group(1)),
urlparse.unquote(path.group(2)),
urlparse.unquote(path.group(3)))
@classmethod
def from_arn_url(cls, url):
"""Generate a new HeatIdentifier by parsing the supplied URL.
The URL is expected to contain a valid arn as part of the path.
"""
# Sanity check the URL
urlp = urlparse.urlparse(url)
if (urlp.scheme not in ('http', 'https') or
not urlp.netloc or not urlp.path):
raise ValueError(_('"%s" is not a valid URL') % url)
# Remove any query-string and extract the ARN
arn_url_prefix = '/arn%3Aopenstack%3Aheat%3A%3A'
match = re.search(arn_url_prefix, urlp.path, re.IGNORECASE)
if match is None:
raise ValueError(_('"%s" is not a valid ARN URL') % url)
# the +1 is to skip the leading /
url_arn = urlp.path[match.start() + 1:]
arn = urlparse.unquote(url_arn)
return cls.from_arn(arn)
def arn(self):
"""Return as an ARN.
Returned in the form:
arn:openstack:heat::<tenant>:stacks/<stack_name>/<stack_id><path>
"""
return 'arn:openstack:heat::%s:%s' % (urlparse.quote(self.tenant, ''),
self._tenant_path())
def arn_url_path(self):
"""Return an ARN quoted correctly for use in a URL."""
return '/' + urlparse.quote(self.arn(), '')
def url_path(self):
"""Return a URL-encoded path segment of a URL.
Returned in the form:
<tenant>/stacks/<stack_name>/<stack_id><path>
"""
return '/'.join((urlparse.quote(self.tenant, ''), self._tenant_path()))
def _tenant_path(self):
"""URL-encoded path segment of a URL within a particular tenant.
Returned in the form:
stacks/<stack_name>/<stack_id><path>
"""
return 'stacks/%s%s' % (self.stack_path(),
urlparse.quote(strutils.safe_encode(
self.path)))
def stack_path(self):
"""Return a URL-encoded path segment of a URL without a tenant.
Returned in the form:
<stack_name>/<stack_id>
"""
return '%s/%s' % (urlparse.quote(self.stack_name, ''),
urlparse.quote(self.stack_id, ''))
def _path_components(self):
"""Return a list of the path components."""
return self.path.lstrip('/').split('/')
def __getattr__(self, attr):
"""Return a component of the identity when accessed as an attribute."""
if attr not in self.FIELDS:
raise AttributeError(_('Unknown attribute "%s"') % attr)
return self.identity[attr]
def __getitem__(self, key):
"""Return one of the components of the identity."""
if key not in self.FIELDS:
raise KeyError(_('Unknown attribute "%s"') % key)
return self.identity[key]
def __len__(self):
"""Return the number of components in an identity."""
return len(self.FIELDS)
def __contains__(self, key):
return key in self.FIELDS
def __iter__(self):
return iter(self.FIELDS)
def __repr__(self):
return repr(dict(self))
class ResourceIdentifier(HeatIdentifier):
"""An identifier for a resource."""
RESOURCE_NAME = 'resource_name'
def __init__(self, tenant, stack_name, stack_id, path,
resource_name=None):
"""Initialise a new Resource identifier.
The identifier is based on the identifier components of
the owning stack and the resource name.
"""
if resource_name is not None:
if '/' in resource_name:
raise ValueError(_('Resource name may not contain "/"'))
path = '/'.join([path.rstrip('/'), 'resources', resource_name])
super(ResourceIdentifier, self).__init__(tenant,
stack_name,
stack_id,
path)
def __getattr__(self, attr):
"""Return a component of the identity when accessed as an attribute."""
if attr == self.RESOURCE_NAME:
return self._path_components()[-1]
return HeatIdentifier.__getattr__(self, attr)
def stack(self):
"""Return a HeatIdentifier for the owning stack."""
return HeatIdentifier(self.tenant, self.stack_name, self.stack_id,
'/'.join(self._path_components()[:-2]))
class EventIdentifier(HeatIdentifier):
"""An identifier for an event."""
(RESOURCE_NAME, EVENT_ID) = (ResourceIdentifier.RESOURCE_NAME, 'event_id')
def __init__(self, tenant, stack_name, stack_id, path,
event_id=None):
"""Initialise a new Event identifier based on components.
The identifier is based on the identifier components of
the associated resource and the event ID.
"""
if event_id is not None:
path = '/'.join([path.rstrip('/'), 'events', event_id])
super(EventIdentifier, self).__init__(tenant,
stack_name,
stack_id,
path)
def __getattr__(self, attr):
"""Return a component of the identity when accessed as an attribute."""
if attr == self.RESOURCE_NAME:
return getattr(self.resource(), attr)
if attr == self.EVENT_ID:
return self._path_components()[-1]
return HeatIdentifier.__getattr__(self, attr)
def resource(self):
"""Return a HeatIdentifier for the owning resource."""
return ResourceIdentifier(self.tenant, self.stack_name, self.stack_id,
'/'.join(self._path_components()[:-2]))
def stack(self):
"""Return a HeatIdentifier for the owning stack."""
return self.resource().stack()