154 lines
5.1 KiB
Python
154 lines
5.1 KiB
Python
# vim: tabstop=4 shiftwidth=4 softtabstop=4
|
|
|
|
#
|
|
# 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 eventlet
|
|
|
|
from heat.common import exception
|
|
from heat.engine import resources
|
|
|
|
from heat.openstack.common import log as logging
|
|
|
|
logger = logging.getLogger('heat.engine.wait_condition')
|
|
|
|
|
|
class WaitConditionHandle(resources.Resource):
|
|
'''
|
|
the main point of this class is to :
|
|
have no dependancies (so the instance can reference it)
|
|
generate a unique url (to be returned in the refernce)
|
|
then the cfn-signal will use this url to post to and
|
|
WaitCondition will poll it to see if has been written to.
|
|
'''
|
|
properties_schema = {}
|
|
|
|
def __init__(self, name, json_snippet, stack):
|
|
super(WaitConditionHandle, self).__init__(name, json_snippet, stack)
|
|
|
|
def handle_create(self):
|
|
self.instance_id = '%s/stacks/%s/resources/%s' % \
|
|
(resources.Metadata.server(),
|
|
self.stack.id,
|
|
self.name)
|
|
|
|
def handle_update(self):
|
|
return self.UPDATE_REPLACE
|
|
|
|
WAIT_STATUSES = (
|
|
WAITING,
|
|
TIMEDOUT,
|
|
SUCCESS,
|
|
) = (
|
|
'WAITING',
|
|
'TIMEDOUT',
|
|
'SUCCESS',
|
|
)
|
|
|
|
|
|
class WaitCondition(resources.Resource):
|
|
properties_schema = {'Handle': {'Type': 'String',
|
|
'Required': True},
|
|
'Timeout': {'Type': 'Number',
|
|
'Required': True,
|
|
'MinValue': '1'},
|
|
'Count': {'Type': 'Number',
|
|
'MinValue': '1'}}
|
|
|
|
# Sleep time between polling for wait completion
|
|
# is calculated as a fraction of timeout time
|
|
# bounded by MIN_SLEEP and MAX_SLEEP
|
|
MIN_SLEEP = 1 # seconds
|
|
MAX_SLEEP = 10
|
|
SLEEP_DIV = 100 # 1/100'th of timeout
|
|
|
|
def __init__(self, name, json_snippet, stack):
|
|
super(WaitCondition, self).__init__(name, json_snippet, stack)
|
|
self.resource_id = None
|
|
|
|
self.timeout = int(self.t['Properties']['Timeout'])
|
|
self.count = int(self.t['Properties'].get('Count', '1'))
|
|
self.sleep_time = max(min(self.MAX_SLEEP,
|
|
self.timeout / self.SLEEP_DIV),
|
|
self.MIN_SLEEP)
|
|
|
|
def _get_handle_resource_id(self):
|
|
if self.resource_id is None:
|
|
self.calculate_properties()
|
|
handle_url = self.properties['Handle']
|
|
self.resource_id = handle_url.split('/')[-1]
|
|
return self.resource_id
|
|
|
|
def _get_status_reason(self, handle):
|
|
return (handle.metadata.get('Status', WAITING),
|
|
handle.metadata.get('Reason', 'Reason not provided'))
|
|
|
|
def _create_timeout(self):
|
|
return eventlet.Timeout(self.timeout)
|
|
|
|
def handle_create(self):
|
|
tmo = None
|
|
try:
|
|
# keep polling our Metadata to see if the cfn-signal has written
|
|
# it yet. The execution here is limited by timeout.
|
|
with self._create_timeout() as tmo:
|
|
handle = self.stack[self._get_handle_resource_id()]
|
|
|
|
(status, reason) = (WAITING, '')
|
|
|
|
while status == WAITING:
|
|
(status, reason) = self._get_status_reason(handle)
|
|
if status == WAITING:
|
|
logger.debug('Polling for WaitCondition completion,' +
|
|
' sleeping for %s seconds, timeout %s' %
|
|
(self.sleep_time, self.timeout))
|
|
eventlet.sleep(self.sleep_time)
|
|
|
|
except eventlet.Timeout as t:
|
|
if t is not tmo:
|
|
# not my timeout
|
|
raise
|
|
else:
|
|
(status, reason) = (TIMEDOUT, 'Timed out waiting for instance')
|
|
|
|
if status != SUCCESS:
|
|
raise exception.Error(reason)
|
|
|
|
def handle_update(self):
|
|
return self.UPDATE_REPLACE
|
|
|
|
def handle_delete(self):
|
|
self._get_handle_resource_id()
|
|
if self.resource_id is None:
|
|
return
|
|
|
|
handle = self.stack[self.resource_id]
|
|
handle.metadata = {}
|
|
|
|
def FnGetAtt(self, key):
|
|
res = None
|
|
if key == 'Data':
|
|
try:
|
|
meta = self.metadata
|
|
if meta and 'Data' in meta:
|
|
res = meta['Data']
|
|
except Exception as ex:
|
|
pass
|
|
|
|
else:
|
|
raise exception.InvalidTemplateAttribute(resource=self.name,
|
|
key=key)
|
|
|
|
logger.debug('%s.GetAtt(%s) == %s' % (self.name, key, res))
|
|
return unicode(res)
|