def delete(self, retain_resources=[]):
"""
Delete a Stack, optionally retraining certain resources.
Waits for Stack to delete and prints Events if deletion fails
:param list retain_resources: List of LogicalIds to retain
:raises StackError: if deletion fails
"""
if not self.stack:
raise ValidationError(f'Stack {self.config.stack_name} not found')
if not StackStatus.is_deletable(self.stack):
raise ValidationError(f'Stack {self.config.stack_name} is not in a deletable status: '
f'{StackStatus.get_status(self.stack).name}')
info(f'\nDeleting Stack {self.config.stack_name}')
last_timestamp = self.get_last_timestamp()
try:
self.client.delete_stack(StackName=self.config.stack_name, RetainResources=retain_resources)
self.client.get_waiter('stack_delete_complete').wait(
StackName=self.config.stack_name,
WaiterConfig={'Delay': 10, 'MaxAttempts': 360})
info(f'\nDeletion of Stack {self.config.stack_name} successfully completed')
self.stack = None
except ClientError as ce:
raise StackError(ce)
except WaiterError as we:
error(f'\nDeletion of Stack {self.config.stack_name} failed:\n')
self.print_events(last_timestamp)
raise StackError(we)
def execute_change_set(self):
"""
Execute a ChangeSet, waiting for execution to complete and printing the details of Stack Events
caused by this ChangeSet
:raises StackError: If there is an error executing the ChangeSet
"""
last_timestamp = self.get_last_timestamp()
try:
info(f'\nExecuting ChangeSet {self.change_set_name} for {self.config.stack_name}')
self.client.execute_change_set(ChangeSetName=self.change_set_name, StackName=self.config.stack_name)
waiter_name = 'stack_create_complete' if StackStatus.is_creatable(self.stack) else 'stack_update_complete'
self.client.get_waiter(waiter_name).wait(StackName=self.config.stack_name,
WaiterConfig={'Delay': 10, 'MaxAttempts': 360})
info(f'\nChangeSet {self.change_set_name} for {self.config.stack_name} successfully completed:\n')
self.print_events(last_timestamp)
except ClientError as ce:
raise StackError(ce)
except WaiterError as we:
error(f'\nChangeSet {self.change_set_name} for {self.config.stack_name} failed:\n')
self.print_events(last_timestamp)
raise StackError(we)
def deploy(self):
"""
Create a new Stack or update an existing Stack using a ChangeSet.
This will wait for ChangeSet to be created and print the details,
and if Auto-Approve is set, will then execute the ChangeSet and wait for that to complete.
If there are no changes in the ChangeSet it will be automatically deleted.
:raises StackError: If creating the ChangeSet or executing it fails
"""
if not StackStatus.is_creatable(self.stack) and not StackStatus.is_updatable(self.stack):
stack_status = StackStatus.get_status(self.stack)
if stack_status == StackStatus.ROLLBACK_COMPLETE:
warn(f'Deleting Stack {self.config.stack_name} in ROLLBACK_COMPLETE status before attempting to create')
self.delete()
else:
raise ValidationError(f'Stack {self.config.stack_name} is not in a deployable status: '
f'{stack_status.name}')
info(f'\nCreating ChangeSet {self.change_set_name}\n')
try:
self.client.create_change_set(**self.build_change_set_args())
if self.wait_for_change_set():
if self.auto_approve:
self.execute_change_set()
else:
self.pending_change_set()
except ClientError as ce:
raise StackError(ce)
def load_stack(self):
"""
Load Description of stack to determine if it exists and the current status
:return: Matching stack of None
"""
try:
stacks = self.client.describe_stacks(
StackName=self.config.stack_name)['Stacks']
stack = stacks[0]
return stack
except ClientError as ce:
if ce.response['Error']['Code'] == 'ValidationError':
return None
else:
raise StackError(ce)
def wait_for_change_set(self):
"""
Wait for a ChangeSet to be created, printing the details when it is created.
:return: True if ChangeSet created, False if there are no changes
:raises StackError: If creation of ChangeSet fails for reason other than no changes
"""
try:
self.client.get_waiter('change_set_create_complete').wait(
ChangeSetName=self.change_set_name,
StackName=self.config.stack_name,
WaiterConfig={
'Delay': 5,
'MaxAttempts': 120
})
except WaiterError as we:
resp = we.last_response
status = resp['Status']
reason = resp['StatusReason']
# See SAM CLI: https://github.com/awslabs/aws-sam-cli/blob/develop/samcli/lib/deploy/deployer.py#L272
if (status == 'FAILED'
and "The submitted information didn't contain changes."
in reason or 'No updates are to be performed' in reason):
warn('No changes to Stack {}'.format(self.config.stack_name))
self.client.delete_change_set(
ChangeSetName=self.change_set_name,
StackName=self.config.stack_name)
return False
raise StackError(
f'ChangeSet creation failed - Status: {status}, Reason: {reason}'
)
describe_change_set_response = self.client.describe_change_set(
ChangeSetName=self.change_set_name,
StackName=self.config.stack_name)
data = [[
change['ResourceChange']['Action'],
change['ResourceChange']['LogicalResourceId'],
change['ResourceChange']['ResourceType'],
change['ResourceChange'].get('Replacement', '-')
] for change in describe_change_set_response['Changes']]
table(data,
['Action', 'LogicalResourceId', 'ResourceType', 'Replacement'])
return True