# # 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 hashlib import json from oslo_config import cfg from oslo_log import log as logging from oslo_serialization import jsonutils from oslo_utils import excutils import six from heat.common import exception from heat.common.i18n import _ from heat.common.i18n import _LE from heat.common.i18n import _LW from heat.common import identifier from heat.common import template_format from heat.engine import attributes from heat.engine import environment from heat.engine import resource from heat.engine import scheduler from heat.engine import stack as parser from heat.engine import template from heat.rpc import api as rpc_api LOG = logging.getLogger(__name__) class StackResource(resource.Resource): ''' An abstract Resource subclass that allows the management of an entire Stack as a resource in a parent stack. ''' # Assume True as this is evaluated before the stack is created # so there is no way to know for sure without subclass-specific # template parsing. requires_deferred_auth = True def __init__(self, name, json_snippet, stack): super(StackResource, self).__init__(name, json_snippet, stack) self._nested = None self.resource_info = None def validate(self): super(StackResource, self).validate() self.validate_nested_stack() def validate_nested_stack(self): try: name = "%s-%s" % (self.stack.name, self.name) nested_stack = self._parse_nested_stack( name, self.child_template(), self.child_params()) nested_stack.strict_validate = False nested_stack.validate() except AssertionError: raise except Exception as ex: raise exception.StackValidationFailed( error=_("Failed to validate"), path=[self.stack.t.get_section_name('resources'), self.name], message=six.text_type(ex)) def _outputs_to_attribs(self, json_snippet): outputs = json_snippet.get('Outputs') if not self.attributes and outputs: self.attributes_schema = ( attributes.Attributes.schema_from_outputs(outputs)) self.attributes = attributes.Attributes(self.name, self.attributes_schema, self._resolve_attribute) def _needs_update(self, after, before, after_props, before_props, prev_resource): # Issue an update to the nested stack if the stack resource # is able to update. If return true, let the individual # resources in it decide if they need updating. # FIXME (ricolin): seems currently can not call super here if self.nested() is None and ( self.status == self.FAILED or (self.action == self.INIT and self.status == self.COMPLETE)): raise resource.UpdateReplace(self) return True @scheduler.wrappertask def update(self, after, before=None, prev_resource=None): try: yield super(StackResource, self).update(after, before, prev_resource) except StopIteration: with excutils.save_and_reraise_exception(): stack_identity = identifier.HeatIdentifier( self.context.tenant_id, self.physical_resource_name(), self.resource_id) self.rpc_client().stack_cancel_update(self.context, stack_identity) def nested(self, force_reload=False, show_deleted=False): '''Return a Stack object representing the nested (child) stack. :param force_reload: Forces reloading from the DB instead of returning the locally cached Stack object :param show_deleted: Returns the stack even if it's been deleted ''' if force_reload: self._nested = None if self._nested is None and self.resource_id is not None: self._nested = parser.Stack.load(self.context, self.resource_id, show_deleted=show_deleted, force_reload=force_reload) if self._nested is None: raise exception.NotFound(_("Nested stack not found in DB")) return self._nested def child_template(self): ''' Default implementation to get the child template. Resources that inherit from StackResource should override this method with specific details about the template used by them. ''' raise NotImplementedError() def child_params(self): ''' Default implementation to get the child params. Resources that inherit from StackResource should override this method with specific details about the parameters used by them. ''' raise NotImplementedError() def preview(self): ''' Preview a StackResource as resources within a Stack. This method overrides the original Resource.preview to return a preview of all the resources contained in this Stack. For this to be possible, the specific resources need to override both ``child_template`` and ``child_params`` with specific information to allow the stack to be parsed correctly. If any of these methods is missing, the entire StackResource will be returned as if it were a regular Resource. ''' try: child_template = self.child_template() params = self.child_params() except NotImplementedError: LOG.warn(_LW("Preview of '%s' not yet implemented"), self.__class__.__name__) return self name = "%s-%s" % (self.stack.name, self.name) self._nested = self._parse_nested_stack(name, child_template, params) return self.nested().preview_resources() def _parse_child_template(self, child_template, child_env): parsed_child_template = child_template if isinstance(parsed_child_template, template.Template): parsed_child_template = parsed_child_template.t return template.Template(parsed_child_template, files=self.stack.t.files, env=child_env) def _parse_nested_stack(self, stack_name, child_template, child_params, timeout_mins=None, adopt_data=None): if timeout_mins is None: timeout_mins = self.stack.timeout_mins stack_user_project_id = self.stack.stack_user_project_id new_nested_depth = self._child_nested_depth() child_env = environment.get_child_environment( self.stack.env, child_params, child_resource_name=self.name, item_to_remove=self.resource_info) parsed_template = self._child_parsed_template(child_template, child_env) # Note we disable rollback for nested stacks, since they # should be rolled back by the parent stack on failure nested = parser.Stack(self.context, stack_name, parsed_template, timeout_mins=timeout_mins, disable_rollback=True, parent_resource=self.name, owner_id=self.stack.id, user_creds_id=self.stack.user_creds_id, stack_user_project_id=stack_user_project_id, adopt_stack_data=adopt_data, nested_depth=new_nested_depth) return nested def _child_nested_depth(self): if self.stack.nested_depth >= cfg.CONF.max_nested_stack_depth: msg = _("Recursion depth exceeds %d." ) % cfg.CONF.max_nested_stack_depth raise exception.RequestLimitExceeded(message=msg) return self.stack.nested_depth + 1 def _child_parsed_template(self, child_template, child_env): parsed_template = self._parse_child_template(child_template, child_env) self._validate_nested_resources(parsed_template) # Don't overwrite the attributes_schema for subclasses that # define their own attributes_schema. if not hasattr(type(self), 'attributes_schema'): self.attributes = None self._outputs_to_attribs(parsed_template) return parsed_template def _validate_nested_resources(self, templ): if cfg.CONF.max_resources_per_stack == -1: return root_stack_id = self.stack.root_stack_id() total_resources = (len(templ[templ.RESOURCES]) + self.stack.total_resources(root_stack_id)) if self.nested(): # It's an update and these resources will be deleted total_resources -= len(self.nested().resources) if (total_resources > cfg.CONF.max_resources_per_stack): message = exception.StackResourceLimitExceeded.msg_fmt raise exception.RequestLimitExceeded(message=message) def create_with_template(self, child_template, user_params=None, timeout_mins=None, adopt_data=None): """Create the nested stack with the given template.""" name = self.physical_resource_name() if timeout_mins is None: timeout_mins = self.stack.timeout_mins stack_user_project_id = self.stack.stack_user_project_id if user_params is None: user_params = self.child_params() child_env = environment.get_child_environment( self.stack.env, user_params, child_resource_name=self.name, item_to_remove=self.resource_info) new_nested_depth = self._child_nested_depth() parsed_template = self._child_parsed_template(child_template, child_env) adopt_data_str = None if adopt_data is not None: if 'environment' not in adopt_data: adopt_data['environment'] = child_env.user_env_as_dict() if 'template' not in adopt_data: adopt_data['template'] = child_template adopt_data_str = json.dumps(adopt_data) args = {rpc_api.PARAM_TIMEOUT: timeout_mins, rpc_api.PARAM_DISABLE_ROLLBACK: True, rpc_api.PARAM_ADOPT_STACK_DATA: adopt_data_str} try: result = self.rpc_client()._create_stack( self.context, name, parsed_template.t, child_env.user_env_as_dict(), parsed_template.files, args, owner_id=self.stack.id, user_creds_id=self.stack.user_creds_id, stack_user_project_id=stack_user_project_id, nested_depth=new_nested_depth, parent_resource_name=self.name) except Exception as ex: self.raise_local_exception(ex) self.resource_id_set(result['stack_id']) def raise_local_exception(self, ex): if (isinstance(ex, exception.ActionInProgress) and self.stack.action == self.stack.ROLLBACK): # The update was interrupted and the rollback is already in # progress, so just ignore the error and wait for the rollback to # finish return if not ex.__class__.__name__.endswith('_Remote'): raise ex full_message = six.text_type(ex) if full_message.find('\n') > -1: message, msg_trace = full_message.split('\n', 1) else: message = full_message raise exception.ResourceFailure(message, self, action=self.action) def check_create_complete(self, cookie=None): return self._check_status_complete(resource.Resource.CREATE) def _check_status_complete(self, action, show_deleted=False, cookie=None): try: nested = self.nested(force_reload=True, show_deleted=show_deleted) except exception.NotFound: if action == resource.Resource.DELETE: return True # It's possible the engine handling the create hasn't persisted # the stack to the DB when we first start polling for state return False if nested is None: return True if nested.action != action: return False # Has the action really started? # # The rpc call to update does not guarantee that the stack will be # placed into IN_PROGRESS by the time it returns (it runs stack.update # in a thread) so you could also have a situation where we get into # this method and the update hasn't even started. # # So we are using a mixture of state (action+status) and updated_at # to see if the action has actually progressed. # - very fast updates (like something with one RandomString) we will # probably miss the state change, but we should catch the updated_at. # - very slow updates we won't see the updated_at for quite a while, # but should see the state change. if cookie is not None: prev_state = cookie['previous']['state'] prev_updated_at = cookie['previous']['updated_at'] if (prev_updated_at == nested.updated_time and prev_state == nested.state): return False if nested.status == resource.Resource.IN_PROGRESS: return False elif nested.status == resource.Resource.COMPLETE: return True elif nested.status == resource.Resource.FAILED: raise exception.ResourceFailure(nested.status_reason, self, action=action) else: raise resource.ResourceUnknownStatus( resource_status=nested.status, status_reason=nested.status_reason, result=_('Stack unknown status')) def check_adopt_complete(self, cookie=None): return self._check_status_complete(resource.Resource.ADOPT) def update_with_template(self, child_template, user_params=None, timeout_mins=None): """Update the nested stack with the new template.""" if self.id is None: self._store() nested_stack = self.nested() if nested_stack is None: # if the create failed for some reason and the nested # stack was not created, we need to create an empty stack # here so that the update will work. def _check_for_completion(creator_fn): while not self.check_create_complete(creator_fn): yield empty_temp = template_format.parse( "heat_template_version: '2013-05-23'") stack_creator = self.create_with_template(empty_temp, {}) checker = scheduler.TaskRunner(_check_for_completion, stack_creator) checker(timeout=self.stack.timeout_secs()) if stack_creator is not None: stack_creator.run_to_completion() nested_stack = self.nested() if timeout_mins is None: timeout_mins = self.stack.timeout_mins if user_params is None: user_params = self.child_params() child_env = environment.get_child_environment( self.stack.env, user_params, child_resource_name=self.name, item_to_remove=self.resource_info) parsed_template = self._child_parsed_template(child_template, child_env) cookie = {'previous': { 'updated_at': nested_stack.updated_time, 'state': nested_stack.state}} args = {rpc_api.PARAM_TIMEOUT: timeout_mins} try: self.rpc_client().update_stack( self.context, nested_stack.identifier(), parsed_template.t, child_env.user_env_as_dict(), parsed_template.files, args) except Exception as ex: LOG.exception(_LE('update_stack')) self.raise_local_exception(ex) return cookie def check_update_complete(self, cookie=None): return self._check_status_complete(resource.Resource.UPDATE, cookie=cookie) def delete_nested(self): ''' Delete the nested stack. ''' stack_identity = identifier.HeatIdentifier( self.context.tenant_id, self.physical_resource_name(), self.resource_id) try: self.rpc_client().delete_stack(self.context, stack_identity) except Exception as ex: self.rpc_client().ignore_error_named(ex, 'NotFound') def handle_delete(self): return self.delete_nested() def check_delete_complete(self, cookie=None): return self._check_status_complete(resource.Resource.DELETE, show_deleted=True) def handle_suspend(self): stack = self.nested() if stack is None: raise exception.Error(_('Cannot suspend %s, stack not created') % self.name) stack_identity = identifier.HeatIdentifier( self.context.tenant_id, self.physical_resource_name(), self.resource_id) self.rpc_client().stack_suspend(self.context, stack_identity) def check_suspend_complete(self, cookie=None): return self._check_status_complete(resource.Resource.SUSPEND) def handle_resume(self): stack = self.nested() if stack is None: raise exception.Error(_('Cannot resume %s, stack not created') % self.name) stack_identity = identifier.HeatIdentifier( self.context.tenant_id, self.physical_resource_name(), self.resource_id) self.rpc_client().stack_resume(self.context, stack_identity) def check_resume_complete(self, cookie=None): return self._check_status_complete(resource.Resource.RESUME) def handle_check(self): stack = self.nested() if stack is None: raise exception.Error(_('Cannot check %s, stack not created') % self.name) stack_identity = identifier.HeatIdentifier( self.context.tenant_id, self.physical_resource_name(), self.resource_id) self.rpc_client().stack_check(self.context, stack_identity) def check_check_complete(self, cookie=None): return self._check_status_complete(resource.Resource.CHECK) def prepare_abandon(self): return self.nested().prepare_abandon() def get_output(self, op): ''' Return the specified Output value from the nested stack. If the output key does not exist, raise an InvalidTemplateAttribute exception. ''' stack = self.nested() if stack is None: return None if op not in stack.outputs: raise exception.InvalidTemplateAttribute(resource=self.name, key=op) return stack.output(op) def _resolve_attribute(self, name): return self.get_output(name) def implementation_signature(self): schema_names = ([prop for prop in self.properties_schema] + [at for at in self.attributes_schema]) schema_hash = hashlib.sha256(';'.join(schema_names)) definition = {'template': self.child_template(), 'files': self.stack.t.files} definition_hash = hashlib.sha256(jsonutils.dumps(definition)) return (schema_hash.hexdigest(), definition_hash.hexdigest())