222 lines
8.7 KiB
Python
222 lines
8.7 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.
|
|
|
|
from oslo_log import log as logging
|
|
import six
|
|
|
|
from heat.common.i18n import _LI
|
|
from heat.engine import dependencies
|
|
from heat.engine import resource
|
|
from heat.engine import scheduler
|
|
from heat.objects import resource as resource_objects
|
|
|
|
LOG = logging.getLogger(__name__)
|
|
|
|
|
|
class StackUpdate(object):
|
|
"""
|
|
A Task to perform the update of an existing stack to a new template.
|
|
"""
|
|
|
|
def __init__(self, existing_stack, new_stack, previous_stack,
|
|
rollback=False, error_wait_time=None):
|
|
"""Initialise with the existing stack and the new stack."""
|
|
self.existing_stack = existing_stack
|
|
self.new_stack = new_stack
|
|
self.previous_stack = previous_stack
|
|
|
|
self.rollback = rollback
|
|
self.error_wait_time = error_wait_time
|
|
|
|
self.existing_snippets = dict((n, r.frozen_definition())
|
|
for n, r in self.existing_stack.items())
|
|
|
|
def __repr__(self):
|
|
if self.rollback:
|
|
return '%s Rollback' % str(self.existing_stack)
|
|
else:
|
|
return '%s Update' % str(self.existing_stack)
|
|
|
|
@scheduler.wrappertask
|
|
def __call__(self):
|
|
"""Return a co-routine that updates the stack."""
|
|
|
|
cleanup_prev = scheduler.DependencyTaskGroup(
|
|
self.previous_stack.dependencies,
|
|
self._remove_backup_resource,
|
|
reverse=True)
|
|
|
|
self.updater = scheduler.DependencyTaskGroup(
|
|
self.dependencies(),
|
|
self._resource_update,
|
|
error_wait_time=self.error_wait_time)
|
|
|
|
if not self.rollback:
|
|
yield cleanup_prev()
|
|
|
|
try:
|
|
yield self.updater()
|
|
finally:
|
|
self.previous_stack.reset_dependencies()
|
|
|
|
def _resource_update(self, res):
|
|
if res.name in self.new_stack and self.new_stack[res.name] is res:
|
|
return self._process_new_resource_update(res)
|
|
else:
|
|
return self._process_existing_resource_update(res)
|
|
|
|
@scheduler.wrappertask
|
|
def _remove_backup_resource(self, prev_res):
|
|
if prev_res.state not in ((prev_res.INIT, prev_res.COMPLETE),
|
|
(prev_res.DELETE, prev_res.COMPLETE)):
|
|
LOG.debug("Deleting backup resource %s" % prev_res.name)
|
|
yield prev_res.destroy()
|
|
|
|
@staticmethod
|
|
def _exchange_stacks(existing_res, prev_res):
|
|
resource_objects.Resource.exchange_stacks(existing_res.stack.context,
|
|
existing_res.id, prev_res.id)
|
|
prev_stack, existing_stack = prev_res.stack, existing_res.stack
|
|
prev_stack.add_resource(existing_res)
|
|
existing_stack.add_resource(prev_res)
|
|
|
|
@scheduler.wrappertask
|
|
def _create_resource(self, new_res):
|
|
res_name = new_res.name
|
|
|
|
# Clean up previous resource
|
|
if res_name in self.previous_stack:
|
|
prev_res = self.previous_stack[res_name]
|
|
|
|
if prev_res.state not in ((prev_res.INIT, prev_res.COMPLETE),
|
|
(prev_res.DELETE, prev_res.COMPLETE)):
|
|
# Swap in the backup resource if it is in a valid state,
|
|
# instead of creating a new resource
|
|
if prev_res.status == prev_res.COMPLETE:
|
|
LOG.debug("Swapping in backup Resource %s" % res_name)
|
|
self._exchange_stacks(self.existing_stack[res_name],
|
|
prev_res)
|
|
return
|
|
|
|
LOG.debug("Deleting backup Resource %s" % res_name)
|
|
yield prev_res.destroy()
|
|
|
|
# Back up existing resource
|
|
if res_name in self.existing_stack:
|
|
LOG.debug("Backing up existing Resource %s" % res_name)
|
|
existing_res = self.existing_stack[res_name]
|
|
self.previous_stack.add_resource(existing_res)
|
|
existing_res.state_set(existing_res.UPDATE, existing_res.COMPLETE)
|
|
|
|
self.existing_stack.add_resource(new_res)
|
|
|
|
# Save new resource definition to backup stack if it is not
|
|
# present in backup stack template already
|
|
# it allows to resolve all dependencies that existing resource
|
|
# can have if it was copied to backup stack
|
|
if (res_name not in
|
|
self.previous_stack.t[self.previous_stack.t.RESOURCES]):
|
|
LOG.debug("Backing up new Resource %s" % res_name)
|
|
definition = new_res.t.reparse(self.previous_stack,
|
|
new_res.stack.t)
|
|
self.previous_stack.t.add_resource(definition)
|
|
self.previous_stack.t.store(self.previous_stack.context)
|
|
|
|
yield new_res.create()
|
|
|
|
@scheduler.wrappertask
|
|
def _process_new_resource_update(self, new_res):
|
|
res_name = new_res.name
|
|
res_type = new_res.type()
|
|
|
|
if (res_name in self.existing_stack and
|
|
res_type == self.existing_stack[res_name].type()):
|
|
existing_res = self.existing_stack[res_name]
|
|
try:
|
|
yield self._update_in_place(existing_res,
|
|
new_res)
|
|
except resource.UpdateReplace:
|
|
pass
|
|
else:
|
|
# Save updated resource definition to backup stack
|
|
# cause it allows the backup stack resources to be synchronized
|
|
LOG.debug("Backing up updated Resource %s" % res_name)
|
|
definition = existing_res.t.reparse(self.previous_stack,
|
|
existing_res.stack.t)
|
|
self.previous_stack.t.add_resource(definition)
|
|
self.previous_stack.t.store(self.previous_stack.context)
|
|
|
|
LOG.info(_LI("Resource %(res_name)s for stack %(stack_name)s "
|
|
"updated"),
|
|
{'res_name': res_name,
|
|
'stack_name': self.existing_stack.name})
|
|
return
|
|
|
|
yield self._create_resource(new_res)
|
|
|
|
def _update_in_place(self, existing_res, new_res):
|
|
existing_snippet = self.existing_snippets[existing_res.name]
|
|
prev_res = self.previous_stack.get(new_res.name)
|
|
|
|
# Note the new resource snippet is resolved in the context
|
|
# of the existing stack (which is the stack being updated)
|
|
# but with the template of the new stack (in case the update
|
|
# is switching template implementations)
|
|
new_snippet = new_res.t.reparse(self.existing_stack,
|
|
self.new_stack.t)
|
|
|
|
return existing_res.update(new_snippet, existing_snippet,
|
|
prev_resource=prev_res)
|
|
|
|
@scheduler.wrappertask
|
|
def _process_existing_resource_update(self, existing_res):
|
|
res_name = existing_res.name
|
|
|
|
if res_name in self.previous_stack:
|
|
yield self._remove_backup_resource(self.previous_stack[res_name])
|
|
|
|
if res_name in self.new_stack:
|
|
new_res = self.new_stack[res_name]
|
|
if new_res.state == (new_res.INIT, new_res.COMPLETE):
|
|
# Already updated in-place
|
|
return
|
|
|
|
if existing_res.stack is not self.previous_stack:
|
|
yield existing_res.destroy()
|
|
|
|
if res_name not in self.new_stack:
|
|
self.existing_stack.remove_resource(res_name)
|
|
|
|
def dependencies(self):
|
|
'''
|
|
Return a Dependencies object representing the dependencies between
|
|
update operations to move from an existing stack definition to a new
|
|
one.
|
|
'''
|
|
existing_deps = self.existing_stack.dependencies
|
|
new_deps = self.new_stack.dependencies
|
|
|
|
def edges():
|
|
# Create/update the new stack's resources in create order
|
|
for e in new_deps.graph().edges():
|
|
yield e
|
|
# Destroy/cleanup the old stack's resources in delete order
|
|
for e in existing_deps.graph(reverse=True).edges():
|
|
yield e
|
|
# Don't cleanup old resources until after they have been replaced
|
|
for name, res in six.iteritems(self.existing_stack):
|
|
if name in self.new_stack:
|
|
yield (res, self.new_stack[name])
|
|
|
|
return dependencies.Dependencies(edges())
|