Improved auto dependency resolution for StackRef and FortyTwo Legacy Refs

This commit is contained in:
Stefan Reimer 2019-06-15 00:05:15 +00:00
parent 309356b129
commit d3efc7c336
2 changed files with 55 additions and 42 deletions

View File

@ -2,7 +2,7 @@ import logging
__author__ = 'Stefan Reimer'
__email__ = 'stefan@zero-downtimet.net'
__version__ = '0.5.0'
__version__ = '0.5.1'
# Set up logging to ``/dev/null`` like a library is supposed to.

View File

@ -76,13 +76,12 @@ class Stack(object):
# backwards comp
if 'vars' in _config:
self.options = dict_merge(self.options, _config['vars'])
if 'Mode' in self.options:
self.mode = self.options['Mode']
if 'options' in _config:
self.options = dict_merge(self.options, _config['options'])
if 'Mode' in self.options:
self.mode = self.options['Mode']
if 'Mode' in self.options:
self.mode = self.options['Mode']
if 'dependencies' in _config:
for dep in _config['dependencies']:
@ -98,9 +97,7 @@ class Stack(object):
'Template.Hash': "__HASH__",
'CloudBender.Version': __version__
}
# cfn is provided for old configs
_config = {'mode': self.mode, 'options': self.options, 'metadata': template_metadata, 'cfn': self.options}
_config = {'mode': self.mode, 'options': self.options, 'metadata': template_metadata}
jenv = JinjaEnv(self.ctx['artifact_paths'])
jenv.globals['_config'] = _config
@ -118,21 +115,42 @@ class Stack(object):
logger.error(self.cfn_template)
raise e
# Some sanity checks and final cosmetics
if not re.search('CloudBender::', self.cfn_template):
logger.info("CloudBender not required -> removing Transform and Conglomerate parameter")
self.cfn_template = self.cfn_template.replace('Transform: [CloudBender]', '')
_res = """
Conglomerate:
Type: String
Description: Project / Namespace this stack is part of
"""
self.cfn_template = re.sub(_res, '', self.cfn_template)
# Add Legacy FortyTwo resource to prevent AWS from replacing existing resources for NO reason ;-(
include = []
search_refs(self.cfn_data, include)
if len(include) and 'Legacy' in self.options:
_res = """
FortyTwo:
Type: Custom::FortyTwo
Properties:
ServiceToken:
Fn::Sub: "arn:aws:lambda:${{AWS::Region}}:${{AWS::AccountId}}:function:FortyTwo"
UpdateToken: __HASH__
Include: {}""".format(sorted(set(include)))
self.cfn_template = re.sub(r'Resources:', r'Resources:' + _res + '\n', self.cfn_template)
logger.info("Legacy Mode -> added Custom::FortyTwo")
# Re-read updated template
self.cfn_data = yaml.safe_load(self.cfn_template)
# Check for empty top level Parameters, Outputs and Conditions and remove
for key in ['Parameters', 'Outputs', 'Conditions']:
if key in self.cfn_data and self.cfn_data[key] is None:
# Delete from data structure which also takes care of json
if key in self.cfn_data and not self.cfn_data[key]:
del self.cfn_data[key]
# but also remove from rendered for the yaml file
self.cfn_template = self.cfn_template.replace('\n' + key + ":", '')
if not re.search('CloudBender::', self.cfn_template):
logger.info("CloudBender not required -> removing Transform")
del self.cfn_data['Transform']
self.cfn_template = self.cfn_template.replace('Transform: [CloudBender]', '')
# Remove and condense multiple empty lines
self.cfn_template = re.sub(r'\n\s*\n', '\n\n', self.cfn_template)
self.cfn_template = re.sub(r'^\s*', '', self.cfn_template)
@ -140,38 +158,26 @@ class Stack(object):
# set md5 last
self.md5 = hashlib.md5(self.cfn_template.encode('utf-8')).hexdigest()
self.cfn_data['Metadata']['Hash'] = self.md5
# Add Legacy FortyTwo if needed to prevent AWS from replacing existing resources for NO reason ;-(
include = []
search_attributes(self.cfn_data, include)
if len(include):
_res = """
FortyTwo:
Type: Custom::FortyTwo
Properties:
ServiceToken:
Fn::Sub: "arn:aws:lambda:${{AWS::Region}}:${{AWS::AccountId}}:function:FortyTwo"
UpdateToken: {}
Include: {}""".format(self.md5, sorted(set(include)))
self.cfn_data['Resources'].update(yaml.safe_load(_res))
self.cfn_template = re.sub(r'Resources:', r'Resources:' + _res + '\n', self.cfn_template)
logger.info("Legacy Mode -> added Custom::FortyTwo")
self.cfn_template = self.cfn_template.replace('__HASH__', self.md5)
# Update internal data structures
self._parse_metadata()
print(self.dependencies)
def _parse_metadata(self):
# Extract dependencies if present
# Extract dependencies
try:
for dep in self.cfn_data['Metadata']['CloudBender']['Dependencies']:
self.dependencies.add(dep)
except KeyError:
pass
# Add CloudBender or FortyTwo dependencies
include = []
search_refs(self.cfn_data, include)
for ref in include:
self.dependencies.add(ref.split('.')[0])
def write_template_file(self):
if self.cfn_template:
yaml_file = os.path.join(self.ctx['template_path'], self.rel_path, self.stackname + ".yaml")
@ -497,21 +503,28 @@ class Stack(object):
os.makedirs(os.path.join(self.ctx[path], self.rel_path))
def search_attributes(template, attributes):
def search_refs(template, attributes):
""" Traverses a template and searches for all Fn::GetAtt calls to FortyTwo
adding them to the passed in attributes set
"""
if isinstance(template, dict):
for k, v in template.items():
# Look for Fn::GetAtt
# FortyTwo Fn::GetAtt
if k == "Fn::GetAtt" and isinstance(v, list):
if v[0] == "FortyTwo":
attributes.append(v[1])
# CloudBender::StackRef
if k == "CloudBender::StackRef":
try:
attributes.append(v['StackTags']['Artifact'])
except KeyError:
pass
if isinstance(v, dict) or isinstance(v, list):
search_attributes(v, attributes)
search_refs(v, attributes)
elif isinstance(template, list):
for k in template:
if isinstance(k, dict) or isinstance(k, list):
search_attributes(k, attributes)
search_refs(k, attributes)