def update(self, json_snippet=None): ''' update the resource. Subclasses should provide a handle_update() method to customise update, the base-class handle_update will fail by default. ''' if self.state in (self.CREATE_IN_PROGRESS, self.UPDATE_IN_PROGRESS): return 'Resource update already requested' if not json_snippet: return 'Must specify json snippet for resource update!' logger.info('updating %s' % str(self)) result = self.UPDATE_NOT_IMPLEMENTED try: self.state_set(self.UPDATE_IN_PROGRESS) properties = Properties(self.properties_schema, json_snippet.get('Properties', {}), self.stack.resolve_runtime_data, self.name) properties.validate() if callable(getattr(self, 'handle_update', None)): result = self.handle_update(json_snippet) except Exception as ex: logger.exception('update %s : %s' % (str(self), str(ex))) self.state_set(self.UPDATE_FAILED, str(ex)) return str(ex) or "Error : %s" % type(ex) else: # If resource was updated (with or without interruption), # then we set the resource to UPDATE_COMPLETE if not result == self.UPDATE_REPLACE: self.t = self.stack.resolve_static_data(json_snippet) self.state_set(self.UPDATE_COMPLETE) return result
def update(self, json_snippet=None): ''' update the resource. Subclasses should provide a handle_update() method to customise update, the base-class handle_update will fail by default. ''' if self.state in (self.CREATE_IN_PROGRESS, self.UPDATE_IN_PROGRESS): return 'Resource update already requested' if not json_snippet: return 'Must specify json snippet for resource update!' logger.info('updating %s' % str(self)) result = self.UPDATE_NOT_IMPLEMENTED try: self.state_set(self.UPDATE_IN_PROGRESS) properties = Properties(self.properties_schema, json_snippet.get('Properties', {}), self.stack.resolve_runtime_data, self.name) properties.validate() if callable(getattr(self, 'handle_update', None)): result = self.handle_update(json_snippet) except Exception as ex: logger.exception('update %s : %s' % (str(self), str(ex))) self.state_set(self.UPDATE_FAILED, str(ex)) return str(ex) or "Error : %s" % type(ex) else: # If resource was updated (with or without interruption), # then we set the resource to UPDATE_COMPLETE if not result == self.UPDATE_REPLACE: self.t = self.stack.resolve_static_data(json_snippet) self.state_set(self.UPDATE_COMPLETE) return result
def update(self, after, before=None): """ update the resource. Subclasses should provide a handle_update() method to customise update, the base-class handle_update will fail by default. """ if before is None: before = self.parsed_template() if (self.action, self.status) in ((self.CREATE, self.IN_PROGRESS), (self.UPDATE, self.IN_PROGRESS)): raise exception.ResourceFailure(Exception("Resource update already requested")) logger.info("updating %s" % str(self)) try: self.state_set(self.UPDATE, self.IN_PROGRESS) properties = Properties( self.properties_schema, after.get("Properties", {}), self.stack.resolve_runtime_data, self.name ) properties.validate() tmpl_diff = self.update_template_diff(after, before) prop_diff = self.update_template_diff_properties(after, before) if callable(getattr(self, "handle_update", None)): result = self.handle_update(after, tmpl_diff, prop_diff) except UpdateReplace: logger.debug("Resource %s update requires replacement" % self.name) raise except Exception as ex: logger.exception("update %s : %s" % (str(self), str(ex))) failure = exception.ResourceFailure(ex) self.state_set(self.UPDATE, self.FAILED, str(failure)) raise failure else: self.t = self.stack.resolve_static_data(after) self.state_set(self.UPDATE, self.COMPLETE)
def update(self, json_snippet=None): ''' update the resource. Subclasses should provide a handle_update() method to customise update, the base-class handle_update will fail by default. ''' assert json_snippet is not None, 'Must specify update json snippet' if self.state in (self.CREATE_IN_PROGRESS, self.UPDATE_IN_PROGRESS): raise exception.ResourceFailure(Exception( 'Resource update already requested')) logger.info('updating %s' % str(self)) try: self.state_set(self.UPDATE_IN_PROGRESS) properties = Properties(self.properties_schema, json_snippet.get('Properties', {}), self.stack.resolve_runtime_data, self.name) properties.validate() tmpl_diff = self.update_template_diff(json_snippet) prop_diff = self.update_template_diff_properties(json_snippet) if callable(getattr(self, 'handle_update', None)): result = self.handle_update(json_snippet, tmpl_diff, prop_diff) except UpdateReplace: logger.debug("Resource %s update requires replacement" % self.name) raise except Exception as ex: logger.exception('update %s : %s' % (str(self), str(ex))) failure = exception.ResourceFailure(ex) self.state_set(self.UPDATE_FAILED, str(failure)) raise failure else: self.t = self.stack.resolve_static_data(json_snippet) self.state_set(self.UPDATE_COMPLETE)
def update(self, json_snippet=None): ''' update the resource. Subclasses should provide a handle_update() method to customise update, the base-class handle_update will fail by default. ''' assert json_snippet is not None, 'Must specify update json snippet' if self.state in (self.CREATE_IN_PROGRESS, self.UPDATE_IN_PROGRESS): raise exception.ResourceFailure( Exception('Resource update already requested')) logger.info('updating %s' % str(self)) try: self.state_set(self.UPDATE_IN_PROGRESS) properties = Properties(self.properties_schema, json_snippet.get('Properties', {}), self.stack.resolve_runtime_data, self.name) properties.validate() tmpl_diff = self.update_template_diff(json_snippet) prop_diff = self.update_template_diff_properties(json_snippet) if callable(getattr(self, 'handle_update', None)): result = self.handle_update(json_snippet, tmpl_diff, prop_diff) except UpdateReplace: logger.debug("Resource %s update requires replacement" % self.name) raise except Exception as ex: logger.exception('update %s : %s' % (str(self), str(ex))) failure = exception.ResourceFailure(ex) self.state_set(self.UPDATE_FAILED, str(failure)) raise failure else: self.t = self.stack.resolve_static_data(json_snippet) self.state_set(self.UPDATE_COMPLETE)
def update(self, after, before=None, prev_resource=None): ''' update the resource. Subclasses should provide a handle_update() method to customise update, the base-class handle_update will fail by default. ''' action = self.UPDATE (cur_class_def, cur_ver) = self.implementation_signature() prev_ver = cur_ver if prev_resource is not None: (prev_class_def, prev_ver) = prev_resource.implementation_signature() if prev_class_def != cur_class_def: raise UpdateReplace(self.name) if before is None: before = self.parsed_template() if prev_ver == cur_ver and before == after: return if (self.action, self.status) in ((self.CREATE, self.IN_PROGRESS), (self.UPDATE, self.IN_PROGRESS), (self.ADOPT, self.IN_PROGRESS)): exc = Exception(_('Resource update already requested')) raise exception.ResourceFailure(exc, self, action) logger.info('updating %s' % str(self)) try: self.updated_time = datetime.utcnow() self.state_set(action, self.IN_PROGRESS) properties = Properties(self.properties_schema, after.get('Properties', {}), self._resolve_runtime_data, self.name, self.context) properties.validate() tmpl_diff = self.update_template_diff(after, before) prop_diff = self.update_template_diff_properties(after, before) if callable(getattr(self, 'handle_update', None)): handle_data = self.handle_update(after, tmpl_diff, prop_diff) yield if callable(getattr(self, 'check_update_complete', None)): while not self.check_update_complete(handle_data): yield except UpdateReplace: with excutils.save_and_reraise_exception(): logger.debug(_("Resource %s update requires replacement") % self.name) except Exception as ex: logger.exception('update %s : %s' % (str(self), str(ex))) failure = exception.ResourceFailure(ex, self, action) self.state_set(action, self.FAILED, str(failure)) raise failure else: self.json_snippet = copy.deepcopy(after) self.reparse() self.state_set(action, self.COMPLETE)
def update(self, after, before=None, prev_resource=None): ''' update the resource. Subclasses should provide a handle_update() method to customise update, the base-class handle_update will fail by default. ''' action = self.UPDATE (cur_class_def, cur_ver) = self.implementation_signature() prev_ver = cur_ver if prev_resource is not None: (prev_class_def, prev_ver) = prev_resource.implementation_signature() if prev_class_def != cur_class_def: raise UpdateReplace(self.name) if before is None: before = self.parsed_template() if prev_ver == cur_ver and before == after: return if (self.action, self.status) in ((self.CREATE, self.IN_PROGRESS), (self.UPDATE, self.IN_PROGRESS), (self.ADOPT, self.IN_PROGRESS)): exc = Exception(_('Resource update already requested')) raise exception.ResourceFailure(exc, self, action) logger.info('updating %s' % str(self)) try: self.updated_time = datetime.utcnow() self.state_set(action, self.IN_PROGRESS) properties = Properties(self.properties_schema, after.get('Properties', {}), self._resolve_runtime_data, self.name, self.context) properties.validate() tmpl_diff = self.update_template_diff(after, before) prop_diff = self.update_template_diff_properties(after, before) if callable(getattr(self, 'handle_update', None)): handle_data = self.handle_update(after, tmpl_diff, prop_diff) yield if callable(getattr(self, 'check_update_complete', None)): while not self.check_update_complete(handle_data): yield except UpdateReplace: with excutils.save_and_reraise_exception(): logger.debug(_("Resource %s update requires replacement") % self.name) except Exception as ex: logger.exception('update %s : %s' % (str(self), str(ex))) failure = exception.ResourceFailure(ex, self, action) self.state_set(action, self.FAILED, str(failure)) raise failure else: self.json_snippet = copy.deepcopy(after) self.reparse() self.state_set(action, self.COMPLETE)
def update(self, after, before=None): ''' update the resource. Subclasses should provide a handle_update() method to customise update, the base-class handle_update will fail by default. ''' action = self.UPDATE if before is None: before = self.parsed_template() if (self.action, self.status) in ((self.CREATE, self.IN_PROGRESS), (self.UPDATE, self.IN_PROGRESS)): exc = Exception(_('Resource update already requested')) raise exception.ResourceFailure(exc, self, action) logger.info('updating %s' % str(self)) try: self.state_set(action, self.IN_PROGRESS) properties = Properties(self.properties_schema, after.get('Properties', {}), self._resolve_runtime_data, self.name) properties.validate() tmpl_diff = self.update_template_diff(after, before) prop_diff = self.update_template_diff_properties(after, before) if callable(getattr(self, 'handle_update', None)): handle_data = self.handle_update(after, tmpl_diff, prop_diff) yield if callable(getattr(self, 'check_update_complete', None)): while not self.check_update_complete(handle_data): yield except UpdateReplace: logger.debug(_("Resource %s update requires replacement") % self.name) raise except Exception as ex: logger.exception('update %s : %s' % (str(self), str(ex))) failure = exception.ResourceFailure(ex, self, action) self.state_set(action, self.FAILED, str(failure)) raise failure else: self.t = self.stack.resolve_static_data(after) self.state_set(action, self.COMPLETE)
def update(self, after, before=None): ''' update the resource. Subclasses should provide a handle_update() method to customise update, the base-class handle_update will fail by default. ''' action = self.UPDATE if before is None: before = self.parsed_template() if (self.action, self.status) in ((self.CREATE, self.IN_PROGRESS), (self.UPDATE, self.IN_PROGRESS)): exc = Exception('Resource update already requested') raise exception.ResourceFailure(exc, self, action) logger.info('updating %s' % str(self)) try: self.state_set(action, self.IN_PROGRESS) properties = Properties(self.properties_schema, after.get('Properties', {}), self._resolve_runtime_data, self.name) properties.validate() tmpl_diff = self.update_template_diff(after, before) prop_diff = self.update_template_diff_properties(after, before) if callable(getattr(self, 'handle_update', None)): handle_data = self.handle_update(after, tmpl_diff, prop_diff) yield if callable(getattr(self, 'check_update_complete', None)): while not self.check_update_complete(handle_data): yield except UpdateReplace: logger.debug("Resource %s update requires replacement" % self.name) raise except Exception as ex: logger.exception('update %s : %s' % (str(self), str(ex))) failure = exception.ResourceFailure(ex, self, action) self.state_set(action, self.FAILED, str(failure)) raise failure else: self.t = self.stack.resolve_static_data(after) self.state_set(action, self.COMPLETE)
class InstanceGroup(stack_resource.StackResource): tags_schema = { 'Key': { 'Type': 'String', 'Required': True }, 'Value': { 'Type': 'String', 'Required': True } } properties_schema = { 'AvailabilityZones': { 'Required': True, 'Type': 'List', 'Description': _('Not Implemented.') }, 'LaunchConfigurationName': { 'Required': True, 'Type': 'String', 'UpdateAllowed': True, 'Description': _('Name of LaunchConfiguration resource.') }, 'Size': { 'Required': True, 'Type': 'Number', 'UpdateAllowed': True, 'Description': _('Desired number of instances.') }, 'LoadBalancerNames': { 'Type': 'List', 'Description': _('List of LoadBalancer resources.') }, 'Tags': { 'Type': 'List', 'Schema': { 'Type': 'Map', 'Schema': tags_schema }, 'Description': _('Tags to attach to this group.') } } update_allowed_keys = ( 'Properties', 'UpdatePolicy', ) attributes_schema = { "InstanceList": _("A comma-delimited list of server ip addresses. " "(Heat extension).") } rolling_update_schema = { 'MinInstancesInService': properties.Schema(properties.Schema.NUMBER, default=0), 'MaxBatchSize': properties.Schema(properties.Schema.NUMBER, default=1), 'PauseTime': properties.Schema(properties.Schema.STRING, default='PT0S') } update_policy_schema = { 'RollingUpdate': properties.Schema(properties.Schema.MAP, schema=rolling_update_schema) } def __init__(self, name, json_snippet, stack): """ UpdatePolicy is currently only specific to InstanceGroup and AutoScalingGroup. Therefore, init is overridden to parse for the UpdatePolicy. """ super(InstanceGroup, self).__init__(name, json_snippet, stack) self.update_policy = Properties(self.update_policy_schema, self.t.get('UpdatePolicy', {}), parent_name=self.name) def validate(self): """ Add validation for update_policy """ super(InstanceGroup, self).validate() if self.update_policy: self.update_policy.validate() policy_name = self.update_policy_schema.keys()[0] if self.update_policy[policy_name]: pause_time = self.update_policy[policy_name]['PauseTime'] if iso8601utils.parse_isoduration(pause_time) > 3600: raise ValueError('Maximum PauseTime is 1 hour.') def get_instance_names(self): """Get a list of resource names of the instances in this InstanceGroup. Failed resources will be ignored. """ return [r.name for r in self.get_instances()] def get_instances(self): """Get a list of all the instance resources managed by this group. Sort the list of instances first by created_time then by name. """ resources = [] if self.nested(): resources = [ resource for resource in self.nested().itervalues() if resource.status != resource.FAILED ] return sorted(resources, key=lambda r: (r.created_time, r.name)) def handle_create(self): """Create a nested stack and add the initial resources to it.""" num_instances = int(self.properties['Size']) initial_template = self._create_template(num_instances) return self.create_with_template(initial_template, {}) def check_create_complete(self, task): """ When stack creation is done, update the load balancer. If any instances failed to be created, delete them. """ done = super(InstanceGroup, self).check_create_complete(task) if done: self._lb_reload() return done def handle_update(self, json_snippet, tmpl_diff, prop_diff): """ If Properties has changed, update self.properties, so we get the new values during any subsequent adjustment. """ if tmpl_diff: # parse update policy if 'UpdatePolicy' in tmpl_diff: self.update_policy = Properties(self.update_policy_schema, json_snippet.get( 'UpdatePolicy', {}), parent_name=self.name) if prop_diff: self.properties = Properties(self.properties_schema, json_snippet.get('Properties', {}), self.stack.resolve_runtime_data, self.name) # Replace instances first if launch configuration has changed if (self.update_policy['RollingUpdate'] and 'LaunchConfigurationName' in prop_diff): policy = self.update_policy['RollingUpdate'] self._replace(int(policy['MinInstancesInService']), int(policy['MaxBatchSize']), policy['PauseTime']) # Get the current capacity, we may need to adjust if # Size has changed if 'Size' in prop_diff: inst_list = self.get_instances() if len(inst_list) != int(self.properties['Size']): self.resize(int(self.properties['Size'])) def _tags(self): """ Make sure that we add a tag that Ceilometer can pick up. These need to be prepended with 'metering.'. """ tags = self.properties.get('Tags') or [] for t in tags: if t['Key'].startswith('metering.'): # the user has added one, don't add another. return tags return tags + [{ 'Key': 'metering.groupname', 'Value': self.FnGetRefId() }] def handle_delete(self): return self.delete_nested() def _get_instance_definition(self): conf_name = self.properties['LaunchConfigurationName'] conf = self.stack.resource_by_refid(conf_name) instance_definition = copy.deepcopy(conf.t) instance_definition['Type'] = 'AWS::EC2::Instance' instance_definition['Properties']['Tags'] = self._tags() if self.properties.get('VPCZoneIdentifier'): instance_definition['Properties']['SubnetId'] = \ self.properties['VPCZoneIdentifier'][0] # resolve references within the context of this stack. return self.stack.resolve_runtime_data(instance_definition) def _create_template(self, num_instances, num_replace=0): """ Create the template for the nested stack of existing and new instances For rolling update, if launch configuration is different, the instance definition should come from the existing instance instead of using the new launch configuration. """ instances = self.get_instances()[-num_instances:] instance_definition = self._get_instance_definition() num_create = num_instances - len(instances) num_replace -= num_create def instance_templates(num_replace): for i in range(num_instances): if i < len(instances): inst = instances[i] if inst.t != instance_definition and num_replace > 0: num_replace -= 1 yield inst.name, instance_definition else: yield inst.name, inst.t else: yield short_id.generate_id(), instance_definition return {"Resources": dict(instance_templates(num_replace))} def _replace(self, min_in_service, batch_size, pause_time): """ Replace the instances in the group using updated launch configuration """ def changing_instances(tmpl): instances = self.get_instances() current = set((i.name, str(i.t)) for i in instances) updated = set((k, str(v)) for k, v in tmpl['Resources'].items()) # includes instances to be updated and deleted affected = set(k for k, v in current ^ updated) return set(i.FnGetRefId() for i in instances if i.name in affected) def pause_between_batch(): while True: try: yield except scheduler.Timeout: return capacity = len(self.nested()) if self.nested() else 0 efft_bat_sz = min(batch_size, capacity) efft_min_sz = min(min_in_service, capacity) pause_sec = iso8601utils.parse_isoduration(pause_time) batch_cnt = (capacity + efft_bat_sz - 1) // efft_bat_sz if pause_sec * (batch_cnt - 1) >= self.stack.timeout_mins * 60: raise ValueError('The current UpdatePolicy will result ' 'in stack update timeout.') # effective capacity includes temporary capacity added to accomodate # the minimum number of instances in service during update efft_capacity = max(capacity - efft_bat_sz, efft_min_sz) + efft_bat_sz try: remainder = capacity while remainder > 0 or efft_capacity > capacity: if capacity - remainder >= efft_min_sz: efft_capacity = capacity template = self._create_template(efft_capacity, efft_bat_sz) self._lb_reload(exclude=changing_instances(template)) updater = self.update_with_template(template, {}) updater.run_to_completion() self.check_update_complete(updater) remainder -= efft_bat_sz if remainder > 0 and pause_sec > 0: self._lb_reload() waiter = scheduler.TaskRunner(pause_between_batch) waiter(timeout=pause_sec) finally: self._lb_reload() def resize(self, new_capacity): """ Resize the instance group to the new capacity. When shrinking, the oldest instances will be removed. """ new_template = self._create_template(new_capacity) try: updater = self.update_with_template(new_template, {}) updater.run_to_completion() self.check_update_complete(updater) finally: # Reload the LB in any case, so it's only pointing at healthy # nodes. self._lb_reload() def _lb_reload(self, exclude=[]): ''' Notify the LoadBalancer to reload its config to include the changes in instances we have just made. This must be done after activation (instance in ACTIVE state), otherwise the instances' IP addresses may not be available. ''' if self.properties['LoadBalancerNames']: id_list = [ inst.FnGetRefId() for inst in self.get_instances() if inst.FnGetRefId() not in exclude ] for lb in self.properties['LoadBalancerNames']: lb_resource = self.stack[lb] if 'Instances' in lb_resource.properties_schema: lb_resource.json_snippet['Properties']['Instances'] = ( id_list) elif 'members' in lb_resource.properties_schema: lb_resource.json_snippet['Properties']['members'] = ( id_list) else: raise exception.Error( "Unsupported resource '%s' in LoadBalancerNames" % (lb, )) resolved_snippet = self.stack.resolve_static_data( lb_resource.json_snippet) scheduler.TaskRunner(lb_resource.update, resolved_snippet)() def FnGetRefId(self): return self.physical_resource_name() def _resolve_attribute(self, name): ''' heat extension: "InstanceList" returns comma delimited list of server ip addresses. ''' if name == 'InstanceList': return u','.join( inst.FnGetAtt('PublicIp') for inst in self.get_instances()) or None
class Resource(object): # Status strings CREATE_IN_PROGRESS = 'IN_PROGRESS' CREATE_FAILED = 'CREATE_FAILED' CREATE_COMPLETE = 'CREATE_COMPLETE' DELETE_IN_PROGRESS = 'DELETE_IN_PROGRESS' DELETE_FAILED = 'DELETE_FAILED' DELETE_COMPLETE = 'DELETE_COMPLETE' UPDATE_IN_PROGRESS = 'UPDATE_IN_PROGRESS' UPDATE_FAILED = 'UPDATE_FAILED' UPDATE_COMPLETE = 'UPDATE_COMPLETE' # Status values, returned from subclasses to indicate update method UPDATE_REPLACE = 'UPDATE_REPLACE' UPDATE_INTERRUPTION = 'UPDATE_INTERRUPTION' UPDATE_NO_INTERRUPTION = 'UPDATE_NO_INTERRUPTION' UPDATE_NOT_IMPLEMENTED = 'UPDATE_NOT_IMPLEMENTED' # If True, this resource must be created before it can be referenced. strict_dependency = True created_time = timestamp.Timestamp(db_api.resource_get, 'created_at') updated_time = timestamp.Timestamp(db_api.resource_get, 'updated_at') metadata = Metadata() # Resource implementation set this to the subset of template keys # which are supported for handle_update, used by update_template_diff update_allowed_keys = () # Resource implementation set this to the subset of resource properties # supported for handle_update, used by update_template_diff_properties update_allowed_properties = () def __new__(cls, name, json, stack): '''Create a new Resource of the appropriate class for its type.''' if cls != Resource: # Call is already for a subclass, so pass it through return super(Resource, cls).__new__(cls) # Select the correct subclass to instantiate ResourceClass = get_class(json['Type']) return ResourceClass(name, json, stack) def __init__(self, name, json_snippet, stack): if '/' in name: raise ValueError(_('Resource name may not contain "/"')) self.stack = stack self.context = stack.context self.name = name self.json_snippet = json_snippet self.t = stack.resolve_static_data(json_snippet) self.cached_t = None self.properties = Properties(self.properties_schema, self.t.get('Properties', {}), self.stack.resolve_runtime_data, self.name) resource = db_api.resource_get_by_name_and_stack(self.context, name, stack.id) if resource: self.resource_id = resource.nova_instance self.state = resource.state self.state_description = resource.state_description self.id = resource.id else: self.resource_id = None self.state = None self.state_description = '' self.id = None def __eq__(self, other): '''Allow == comparison of two resources''' # For the purposes of comparison, we declare two resource objects # equal if their names and parsed_templates are the same if isinstance(other, Resource): return (self.name == other.name) and ( self.parsed_template() == other.parsed_template()) return NotImplemented def __ne__(self, other): '''Allow != comparison of two resources''' result = self.__eq__(other) if result is NotImplemented: return result return not result def type(self): return self.t['Type'] def identifier(self): '''Return an identifier for this resource''' return identifier.ResourceIdentifier(resource_name=self.name, **self.stack.identifier()) def parsed_template(self, section=None, default={}, cached=False): ''' Return the parsed template data for the resource. May be limited to only one section of the data, in which case a default value may also be supplied. ''' if cached and self.cached_t: t = self.cached_t else: t = self.t if section is None: template = t else: template = t.get(section, default) return self.stack.resolve_runtime_data(template) def cache_template(self): ''' make a cache of the resource's parsed template this can then be used via parsed_template(cached=True) ''' self.cached_t = self.stack.resolve_runtime_data(self.t) def update_template_diff(self, json_snippet=None): ''' Returns the difference between json_template and self.t If something has been removed in json_snippet which exists in self.t we set it to None. If any keys have changed which are not in update_allowed_keys, raises NotImplementedError ''' update_allowed_set = set(self.update_allowed_keys) # Create a set containing the keys in both current and update template current_template = self.parsed_template(cached=True) template_keys = set(current_template.keys()) new_template = self.stack.resolve_runtime_data(json_snippet) template_keys.update(set(new_template.keys())) # Create a set of keys which differ (or are missing/added) changed_keys_set = set([k for k in template_keys if current_template.get(k) != new_template.get(k)]) if not changed_keys_set.issubset(update_allowed_set): badkeys = changed_keys_set - update_allowed_set raise NotImplementedError("Cannot update keys %s for %s" % (badkeys, self.name)) return dict((k, new_template.get(k)) for k in changed_keys_set) def update_template_diff_properties(self, json_snippet=None): ''' Returns the changed Properties between json_template and self.t If a property has been removed in json_snippet which exists in self.t we set it to None. If any properties have changed which are not in update_allowed_properties, raises NotImplementedError ''' update_allowed_set = set(self.update_allowed_properties) # Create a set containing the keys in both current and update template tmpl = self.parsed_template(cached=True) current_properties = tmpl.get('Properties', {}) template_properties = set(current_properties.keys()) updated_properties = json_snippet.get('Properties', {}) template_properties.update(set(updated_properties.keys())) # Create a set of keys which differ (or are missing/added) changed_properties_set = set(k for k in template_properties if current_properties.get(k) != updated_properties.get(k)) if not changed_properties_set.issubset(update_allowed_set): badkeys = changed_properties_set - update_allowed_set raise NotImplementedError("Cannot update properties %s for %s" % (badkeys, self.name)) return dict((k, updated_properties.get(k)) for k in changed_properties_set) def __str__(self): return '%s "%s"' % (self.__class__.__name__, self.name) def _add_dependencies(self, deps, fragment): if isinstance(fragment, dict): for key, value in fragment.items(): if key in ('DependsOn', 'Ref'): target = self.stack.resources[value] if key == 'DependsOn' or target.strict_dependency: deps += (self, target) elif key != 'Fn::GetAtt': self._add_dependencies(deps, value) elif isinstance(fragment, list): for item in fragment: self._add_dependencies(deps, item) def add_dependencies(self, deps): self._add_dependencies(deps, self.t) deps += (self, None) def keystone(self): return self.stack.clients.keystone() def nova(self, service_type='compute'): return self.stack.clients.nova(service_type) def swift(self): return self.stack.clients.swift() def quantum(self): return self.stack.clients.quantum() def cinder(self): return self.stack.clients.cinder() def create(self): ''' Create the resource. Subclasses should provide a handle_create() method to customise creation. ''' if self.state in (self.CREATE_IN_PROGRESS, self.CREATE_COMPLETE): return 'Resource creation already requested' logger.info('creating %s' % str(self)) # Re-resolve the template, since if the resource Ref's # the AWS::StackId pseudo parameter, it will change after # the parser.Stack is stored (which is after the resources # are __init__'d, but before they are create()'d) self.t = self.stack.resolve_static_data(self.json_snippet) self.properties = Properties(self.properties_schema, self.t.get('Properties', {}), self.stack.resolve_runtime_data, self.name) try: self.properties.validate() self.state_set(self.CREATE_IN_PROGRESS) if callable(getattr(self, 'handle_create', None)): self.handle_create() while not self.check_active(): eventlet.sleep(1) except greenlet.GreenletExit: raise except Exception as ex: logger.exception('create %s', str(self)) self.state_set(self.CREATE_FAILED, str(ex)) return str(ex) or "Error : %s" % type(ex) else: self.state_set(self.CREATE_COMPLETE) def check_active(self): ''' Check if the resource is active (ready to move to the CREATE_COMPLETE state). By default this happens as soon as the handle_create() method has completed successfully, but subclasses may customise this by overriding this function. ''' return True def update(self, json_snippet=None): ''' update the resource. Subclasses should provide a handle_update() method to customise update, the base-class handle_update will fail by default. ''' if self.state in (self.CREATE_IN_PROGRESS, self.UPDATE_IN_PROGRESS): return 'Resource update already requested' if not json_snippet: return 'Must specify json snippet for resource update!' logger.info('updating %s' % str(self)) result = self.UPDATE_NOT_IMPLEMENTED try: self.state_set(self.UPDATE_IN_PROGRESS) properties = Properties(self.properties_schema, json_snippet.get('Properties', {}), self.stack.resolve_runtime_data, self.name) properties.validate() if callable(getattr(self, 'handle_update', None)): result = self.handle_update(json_snippet) except Exception as ex: logger.exception('update %s : %s' % (str(self), str(ex))) self.state_set(self.UPDATE_FAILED, str(ex)) return str(ex) or "Error : %s" % type(ex) else: # If resource was updated (with or without interruption), # then we set the resource to UPDATE_COMPLETE if not result == self.UPDATE_REPLACE: self.t = self.stack.resolve_static_data(json_snippet) self.state_set(self.UPDATE_COMPLETE) return result def physical_resource_name(self): return '%s.%s' % (self.stack.name, self.name) def physical_resource_name_find(self, resource_name): if resource_name in self.stack: return '%s.%s' % (self.stack.name, resource_name) else: raise IndexError('no such resource') def validate(self): logger.info('Validating %s' % str(self)) return self.properties.validate() def delete(self): ''' Delete the resource. Subclasses should provide a handle_delete() method to customise deletion. ''' if self.state == self.DELETE_COMPLETE: return if self.state == self.DELETE_IN_PROGRESS: return 'Resource deletion already in progress' if self.state == self.CREATE_FAILED: return # Further resources will not be created in a CREATE_FAILED stack. # The state of these resources is None. Do not delete as an # undeleteable stack will result if self.state is None: return logger.info('deleting %s (inst:%s db_id:%s)' % (str(self), self.resource_id, str(self.id))) self.state_set(self.DELETE_IN_PROGRESS) try: if callable(getattr(self, 'handle_delete', None)): self.handle_delete() except Exception as ex: logger.exception('Delete %s', str(self)) self.state_set(self.DELETE_FAILED, str(ex)) return str(ex) or "Error : %s" % type(ex) self.state_set(self.DELETE_COMPLETE) def destroy(self): ''' Delete the resource and remove it from the database. ''' result = self.delete() if result: return result if self.id is None: return try: db_api.resource_get(self.context, self.id).delete() except exception.NotFound: # Don't fail on delete if the db entry has # not been created yet. pass except Exception as ex: logger.exception('Delete %s from DB' % str(self)) return str(ex) or "Error : %s" % type(ex) self.id = None def resource_id_set(self, inst): self.resource_id = inst if self.id is not None: try: rs = db_api.resource_get(self.context, self.id) rs.update_and_save({'nova_instance': self.resource_id}) except Exception as ex: logger.warn('db error %s' % str(ex)) def _store(self): '''Create the resource in the database''' try: rs = {'state': self.state, 'stack_id': self.stack.id, 'nova_instance': self.resource_id, 'name': self.name, 'rsrc_metadata': self.metadata, 'stack_name': self.stack.name} new_rs = db_api.resource_create(self.context, rs) self.id = new_rs.id self.stack.updated_time = datetime.utcnow() except Exception as ex: logger.error('DB error %s' % str(ex)) def _add_event(self, new_state, reason): '''Add a state change event to the database''' ev = event.Event(self.context, self.stack, self, new_state, reason, self.resource_id, self.properties) try: ev.store() except Exception as ex: logger.error('DB error %s' % str(ex)) def _store_or_update(self, new_state, reason): self.state = new_state self.state_description = reason if self.id is not None: try: rs = db_api.resource_get(self.context, self.id) rs.update_and_save({'state': self.state, 'state_description': reason, 'nova_instance': self.resource_id}) self.stack.updated_time = datetime.utcnow() except Exception as ex: logger.error('DB error %s' % str(ex)) # store resource in DB on transition to CREATE_IN_PROGRESS # all other transistions (other than to DELETE_COMPLETE) # should be handled by the update_and_save above.. elif new_state == self.CREATE_IN_PROGRESS: self._store() def state_set(self, new_state, reason="state changed"): old_state = self.state self._store_or_update(new_state, reason) if new_state != old_state: self._add_event(new_state, reason) def FnGetRefId(self): ''' http://docs.amazonwebservices.com/AWSCloudFormation/latest/UserGuide/\ intrinsic-function-reference-ref.html ''' if self.resource_id is not None: return unicode(self.resource_id) else: return unicode(self.name) def FnGetAtt(self, key): ''' http://docs.amazonwebservices.com/AWSCloudFormation/latest/UserGuide/\ intrinsic-function-reference-getatt.html ''' return unicode(self.name) def FnBase64(self, data): ''' http://docs.amazonwebservices.com/AWSCloudFormation/latest/UserGuide/\ intrinsic-function-reference-base64.html ''' return base64.b64encode(data) def handle_update(self, json_snippet=None): raise NotImplementedError("Update not implemented for Resource %s" % type(self)) def metadata_update(self, new_metadata=None): ''' No-op for resources which don't explicitly override this method ''' if new_metadata: logger.warning("Resource %s does not implement metadata update" % self.name)
class InstanceGroup(stack_resource.StackResource): PROPERTIES = ( AVAILABILITY_ZONES, LAUNCH_CONFIGURATION_NAME, SIZE, LOAD_BALANCER_NAMES, TAGS, ) = ( 'AvailabilityZones', 'LaunchConfigurationName', 'Size', 'LoadBalancerNames', 'Tags', ) _TAG_KEYS = ( TAG_KEY, TAG_VALUE, ) = ( 'Key', 'Value', ) properties_schema = { AVAILABILITY_ZONES: properties.Schema( properties.Schema.LIST, _('Not Implemented.'), required=True ), LAUNCH_CONFIGURATION_NAME: properties.Schema( properties.Schema.STRING, _('Name of LaunchConfiguration resource.'), required=True, update_allowed=True ), SIZE: properties.Schema( properties.Schema.NUMBER, _('Desired number of instances.'), required=True, update_allowed=True ), LOAD_BALANCER_NAMES: properties.Schema( properties.Schema.LIST, _('List of LoadBalancer resources.') ), TAGS: properties.Schema( properties.Schema.LIST, _('Tags to attach to this group.'), schema=properties.Schema( properties.Schema.MAP, schema={ TAG_KEY: properties.Schema( properties.Schema.STRING, required=True ), TAG_VALUE: properties.Schema( properties.Schema.STRING, required=True ), }, ) ), } update_allowed_keys = ('Properties', 'UpdatePolicy',) attributes_schema = { "InstanceList": _("A comma-delimited list of server ip addresses. " "(Heat extension).") } rolling_update_schema = { 'MinInstancesInService': properties.Schema(properties.Schema.NUMBER, default=0), 'MaxBatchSize': properties.Schema(properties.Schema.NUMBER, default=1), 'PauseTime': properties.Schema(properties.Schema.STRING, default='PT0S') } update_policy_schema = { 'RollingUpdate': properties.Schema(properties.Schema.MAP, schema=rolling_update_schema) } def __init__(self, name, json_snippet, stack): """ UpdatePolicy is currently only specific to InstanceGroup and AutoScalingGroup. Therefore, init is overridden to parse for the UpdatePolicy. """ super(InstanceGroup, self).__init__(name, json_snippet, stack) self.update_policy = Properties(self.update_policy_schema, self.t.get('UpdatePolicy', {}), parent_name=self.name, context=self.context) def validate(self): """ Add validation for update_policy """ super(InstanceGroup, self).validate() if self.update_policy: self.update_policy.validate() policy_name = self.update_policy_schema.keys()[0] if self.update_policy[policy_name]: pause_time = self.update_policy[policy_name]['PauseTime'] if iso8601utils.parse_isoduration(pause_time) > 3600: raise ValueError('Maximum PauseTime is 1 hour.') def get_instance_names(self): """Get a list of resource names of the instances in this InstanceGroup. Failed resources will be ignored. """ return [r.name for r in self.get_instances()] def get_instances(self): """Get a list of all the instance resources managed by this group. Sort the list of instances first by created_time then by name. """ resources = [] if self.nested(): resources = [resource for resource in self.nested().itervalues() if resource.status != resource.FAILED] return sorted(resources, key=lambda r: (r.created_time, r.name)) def _environment(self): """Return the environment for the nested stack.""" return { environment.PARAMETERS: {}, environment.RESOURCE_REGISTRY: { SCALED_RESOURCE_TYPE: 'AWS::EC2::Instance', }, } def handle_create(self): """Create a nested stack and add the initial resources to it.""" num_instances = int(self.properties[self.SIZE]) initial_template = self._create_template(num_instances) return self.create_with_template(initial_template, self._environment()) def check_create_complete(self, task): """ When stack creation is done, update the load balancer. If any instances failed to be created, delete them. """ done = super(InstanceGroup, self).check_create_complete(task) if done: self._lb_reload() return done def handle_update(self, json_snippet, tmpl_diff, prop_diff): """ If Properties has changed, update self.properties, so we get the new values during any subsequent adjustment. """ if tmpl_diff: # parse update policy if 'UpdatePolicy' in tmpl_diff: self.update_policy = Properties( self.update_policy_schema, json_snippet.get('UpdatePolicy', {}), parent_name=self.name, context=self.context) if prop_diff: self.properties = Properties(self.properties_schema, json_snippet.get('Properties', {}), self.stack.resolve_runtime_data, self.name, self.context) # Replace instances first if launch configuration has changed if (self.update_policy['RollingUpdate'] and self.LAUNCH_CONFIGURATION_NAME in prop_diff): policy = self.update_policy['RollingUpdate'] self._replace(int(policy['MinInstancesInService']), int(policy['MaxBatchSize']), policy['PauseTime']) # Get the current capacity, we may need to adjust if # Size has changed if self.SIZE in prop_diff: inst_list = self.get_instances() if len(inst_list) != int(self.properties[self.SIZE]): self.resize(int(self.properties[self.SIZE])) def _tags(self): """ Make sure that we add a tag that Ceilometer can pick up. These need to be prepended with 'metering.'. """ tags = self.properties.get(self.TAGS) or [] for t in tags: if t[self.TAG_KEY].startswith('metering.'): # the user has added one, don't add another. return tags return tags + [{self.TAG_KEY: 'metering.groupname', self.TAG_VALUE: self.FnGetRefId()}] def handle_delete(self): return self.delete_nested() def _get_instance_definition(self): conf_name = self.properties[self.LAUNCH_CONFIGURATION_NAME] conf = self.stack.resource_by_refid(conf_name) instance_definition = copy.deepcopy(conf.t) instance_definition['Type'] = SCALED_RESOURCE_TYPE instance_definition['Properties']['Tags'] = self._tags() if self.properties.get('VPCZoneIdentifier'): instance_definition['Properties']['SubnetId'] = \ self.properties['VPCZoneIdentifier'][0] # resolve references within the context of this stack. return self.stack.resolve_runtime_data(instance_definition) def _create_template(self, num_instances, num_replace=0): """ Create a template to represent autoscaled instances. Also see heat.scaling.template.resource_templates. """ instance_definition = self._get_instance_definition() old_resources = [(instance.name, instance.t) for instance in self.get_instances()] templates = template.resource_templates( old_resources, instance_definition, num_instances, num_replace) return {"Resources": dict(templates)} def _replace(self, min_in_service, batch_size, pause_time): """ Replace the instances in the group using updated launch configuration """ def changing_instances(tmpl): instances = self.get_instances() serialize_template = functools.partial(json.dumps, sort_keys=True) current = set((i.name, serialize_template(i.t)) for i in instances) updated = set((k, serialize_template(v)) for k, v in tmpl['Resources'].items()) # includes instances to be updated and deleted affected = set(k for k, v in current ^ updated) return set(i.FnGetRefId() for i in instances if i.name in affected) def pause_between_batch(): while True: try: yield except scheduler.Timeout: return capacity = len(self.nested()) if self.nested() else 0 efft_bat_sz = min(batch_size, capacity) efft_min_sz = min(min_in_service, capacity) pause_sec = iso8601utils.parse_isoduration(pause_time) batch_cnt = (capacity + efft_bat_sz - 1) // efft_bat_sz if pause_sec * (batch_cnt - 1) >= self.stack.timeout_mins * 60: raise ValueError('The current UpdatePolicy will result ' 'in stack update timeout.') # effective capacity includes temporary capacity added to accommodate # the minimum number of instances in service during update efft_capacity = max(capacity - efft_bat_sz, efft_min_sz) + efft_bat_sz try: remainder = capacity while remainder > 0 or efft_capacity > capacity: if capacity - remainder >= efft_min_sz: efft_capacity = capacity template = self._create_template(efft_capacity, efft_bat_sz) self._lb_reload(exclude=changing_instances(template)) updater = self.update_with_template(template, self._environment()) updater.run_to_completion() self.check_update_complete(updater) remainder -= efft_bat_sz if remainder > 0 and pause_sec > 0: self._lb_reload() waiter = scheduler.TaskRunner(pause_between_batch) waiter(timeout=pause_sec) finally: self._lb_reload() def resize(self, new_capacity): """ Resize the instance group to the new capacity. When shrinking, the oldest instances will be removed. """ new_template = self._create_template(new_capacity) try: updater = self.update_with_template(new_template, self._environment()) updater.run_to_completion() self.check_update_complete(updater) finally: # Reload the LB in any case, so it's only pointing at healthy # nodes. self._lb_reload() def _lb_reload(self, exclude=[]): ''' Notify the LoadBalancer to reload its config to include the changes in instances we have just made. This must be done after activation (instance in ACTIVE state), otherwise the instances' IP addresses may not be available. ''' if self.properties[self.LOAD_BALANCER_NAMES]: id_list = [inst.FnGetRefId() for inst in self.get_instances() if inst.FnGetRefId() not in exclude] for lb in self.properties[self.LOAD_BALANCER_NAMES]: lb_resource = self.stack[lb] if 'Instances' in lb_resource.properties_schema: lb_resource.json_snippet['Properties']['Instances'] = ( id_list) elif 'members' in lb_resource.properties_schema: lb_resource.json_snippet['Properties']['members'] = ( id_list) else: raise exception.Error( "Unsupported resource '%s' in LoadBalancerNames" % (lb,)) resolved_snippet = self.stack.resolve_static_data( lb_resource.json_snippet) scheduler.TaskRunner(lb_resource.update, resolved_snippet)() def FnGetRefId(self): return self.physical_resource_name() def _resolve_attribute(self, name): ''' heat extension: "InstanceList" returns comma delimited list of server ip addresses. ''' if name == 'InstanceList': return u','.join(inst.FnGetAtt('PublicIp') for inst in self.get_instances()) or None
class Resource(object): # Status strings CREATE_IN_PROGRESS = "IN_PROGRESS" CREATE_FAILED = "CREATE_FAILED" CREATE_COMPLETE = "CREATE_COMPLETE" DELETE_IN_PROGRESS = "DELETE_IN_PROGRESS" DELETE_FAILED = "DELETE_FAILED" DELETE_COMPLETE = "DELETE_COMPLETE" UPDATE_IN_PROGRESS = "UPDATE_IN_PROGRESS" UPDATE_FAILED = "UPDATE_FAILED" UPDATE_COMPLETE = "UPDATE_COMPLETE" # Status values, returned from subclasses to indicate update method UPDATE_REPLACE = "UPDATE_REPLACE" UPDATE_INTERRUPTION = "UPDATE_INTERRUPTION" UPDATE_NO_INTERRUPTION = "UPDATE_NO_INTERRUPTION" UPDATE_NOT_IMPLEMENTED = "UPDATE_NOT_IMPLEMENTED" # If True, this resource must be created before it can be referenced. strict_dependency = True created_time = timestamp.Timestamp(db_api.resource_get, "created_at") updated_time = timestamp.Timestamp(db_api.resource_get, "updated_at") metadata = Metadata() def __new__(cls, name, json, stack): """Create a new Resource of the appropriate class for its type.""" if cls != Resource: # Call is already for a subclass, so pass it through return super(Resource, cls).__new__(cls) # Select the correct subclass to instantiate ResourceClass = get_class(json["Type"]) or GenericResource return ResourceClass(name, json, stack) def __init__(self, name, json_snippet, stack): if "/" in name: raise ValueError(_('Resource name may not contain "/"')) self.stack = stack self.context = stack.context self.name = name self.t = stack.resolve_static_data(json_snippet) self.properties = Properties( self.properties_schema, self.t.get("Properties", {}), self.stack.resolve_runtime_data, self.name ) resource = db_api.resource_get_by_name_and_stack(self.context, name, stack.id) if resource: self.resource_id = resource.nova_instance self.state = resource.state self.state_description = resource.state_description self.id = resource.id else: self.resource_id = None self.state = None self.state_description = "" self.id = None def __eq__(self, other): """Allow == comparison of two resources""" # For the purposes of comparison, we declare two resource objects # equal if their names and parsed_templates are the same if isinstance(other, Resource): return (self.name == other.name) and (self.parsed_template() == other.parsed_template()) return NotImplemented def __ne__(self, other): """Allow != comparison of two resources""" result = self.__eq__(other) if result is NotImplemented: return result return not result def type(self): return self.t["Type"] def identifier(self): """Return an identifier for this resource""" return identifier.ResourceIdentifier(resource_name=self.name, **self.stack.identifier()) def parsed_template(self, section=None, default={}): """ Return the parsed template data for the resource. May be limited to only one section of the data, in which case a default value may also be supplied. """ if section is None: template = self.t else: template = self.t.get(section, default) return self.stack.resolve_runtime_data(template) def __str__(self): return '%s "%s"' % (self.__class__.__name__, self.name) def _add_dependencies(self, deps, fragment): if isinstance(fragment, dict): for key, value in fragment.items(): if key in ("DependsOn", "Ref"): target = self.stack.resources[value] if key == "DependsOn" or target.strict_dependency: deps += (self, target) elif key != "Fn::GetAtt": self._add_dependencies(deps, value) elif isinstance(fragment, list): for item in fragment: self._add_dependencies(deps, item) def add_dependencies(self, deps): self._add_dependencies(deps, self.t) deps += (self, None) def keystone(self): return self.stack.clients.keystone() def nova(self, service_type="compute"): return self.stack.clients.nova(service_type) def swift(self): return self.stack.clients.swift() def quantum(self): return self.stack.clients.quantum() def create(self): """ Create the resource. Subclasses should provide a handle_create() method to customise creation. """ if self.state in (self.CREATE_IN_PROGRESS, self.CREATE_COMPLETE): return "Resource creation already requested" logger.info("creating %s" % str(self)) try: err = self.properties.validate() if err: return err self.state_set(self.CREATE_IN_PROGRESS) if callable(getattr(self, "handle_create", None)): self.handle_create() except Exception as ex: # If we get a GreenletExit exception, the create thread has # been killed so we should raise allowing this thread to exit if type(ex) is greenlet.GreenletExit: logger.warning("GreenletExit during create, exiting") raise else: logger.exception("create %s", str(self)) self.state_set(self.CREATE_FAILED, str(ex)) return str(ex) else: self.state_set(self.CREATE_COMPLETE) def update(self, json_snippet=None): """ update the resource. Subclasses should provide a handle_update() method to customise update, the base-class handle_update will fail by default. """ if self.state in (self.CREATE_IN_PROGRESS, self.UPDATE_IN_PROGRESS): return "Resource update already requested" if not json_snippet: return "Must specify json snippet for resource update!" logger.info("updating %s" % str(self)) result = self.UPDATE_NOT_IMPLEMENTED try: self.state_set(self.UPDATE_IN_PROGRESS) self.t = self.stack.resolve_static_data(json_snippet) err = self.properties.validate() if err: return err if callable(getattr(self, "handle_update", None)): result = self.handle_update() except Exception as ex: logger.exception("update %s : %s" % (str(self), str(ex))) self.state_set(self.UPDATE_FAILED, str(ex)) return str(ex) else: # If resource was updated (with or without interruption), # then we set the resource to UPDATE_COMPLETE if not result == self.UPDATE_REPLACE: self.state_set(self.UPDATE_COMPLETE) return result def physical_resource_name(self): return "%s.%s" % (self.stack.name, self.name) def physical_resource_name_find(self, resource_name): if resource_name in self.stack: return "%s.%s" % (self.stack.name, resource_name) else: raise IndexError("no such resource") def validate(self): logger.info("Validating %s" % str(self)) return self.properties.validate() def delete(self): """ Delete the resource. Subclasses should provide a handle_delete() method to customise deletion. """ if self.state == self.DELETE_COMPLETE: return if self.state == self.DELETE_IN_PROGRESS: return "Resource deletion already in progress" logger.info("deleting %s (inst:%s db_id:%s)" % (str(self), self.resource_id, str(self.id))) self.state_set(self.DELETE_IN_PROGRESS) try: if callable(getattr(self, "handle_delete", None)): self.handle_delete() except Exception as ex: logger.exception("Delete %s", str(self)) self.state_set(self.DELETE_FAILED, str(ex)) return str(ex) self.state_set(self.DELETE_COMPLETE) def destroy(self): """ Delete the resource and remove it from the database. """ result = self.delete() if result: return result if self.id is None: return try: db_api.resource_get(self.context, self.id).delete() except exception.NotFound: # Don't fail on delete if the db entry has # not been created yet. pass except Exception as ex: logger.exception("Delete %s from DB" % str(self)) return str(ex) self.id = None def resource_id_set(self, inst): self.resource_id = inst if self.id is not None: try: rs = db_api.resource_get(self.context, self.id) rs.update_and_save({"nova_instance": self.resource_id}) except Exception as ex: logger.warn("db error %s" % str(ex)) def _store(self): """Create the resource in the database""" try: rs = { "state": self.state, "stack_id": self.stack.id, "nova_instance": self.resource_id, "name": self.name, "rsrc_metadata": self.metadata, "stack_name": self.stack.name, } new_rs = db_api.resource_create(self.context, rs) self.id = new_rs.id self.stack.updated_time = datetime.utcnow() except Exception as ex: logger.error("DB error %s" % str(ex)) def _add_event(self, new_state, reason): """Add a state change event to the database""" ev = event.Event(self.context, self.stack, self, new_state, reason, self.resource_id, self.properties) try: ev.store() except Exception as ex: logger.error("DB error %s" % str(ex)) def _store_or_update(self, new_state, reason): self.state = new_state self.state_description = reason if self.id is not None: try: rs = db_api.resource_get(self.context, self.id) rs.update_and_save( {"state": self.state, "state_description": reason, "nova_instance": self.resource_id} ) self.stack.updated_time = datetime.utcnow() except Exception as ex: logger.error("DB error %s" % str(ex)) # store resource in DB on transition to CREATE_IN_PROGRESS # all other transistions (other than to DELETE_COMPLETE) # should be handled by the update_and_save above.. elif new_state == self.CREATE_IN_PROGRESS: self._store() def state_set(self, new_state, reason="state changed"): old_state = self.state self._store_or_update(new_state, reason) if new_state != old_state: self._add_event(new_state, reason) def FnGetRefId(self): """ http://docs.amazonwebservices.com/AWSCloudFormation/latest/UserGuide/\ intrinsic-function-reference-ref.html """ if self.resource_id is not None: return unicode(self.resource_id) else: return unicode(self.name) def FnGetAtt(self, key): """ http://docs.amazonwebservices.com/AWSCloudFormation/latest/UserGuide/\ intrinsic-function-reference-getatt.html """ return unicode(self.name) def FnBase64(self, data): """ http://docs.amazonwebservices.com/AWSCloudFormation/latest/UserGuide/\ intrinsic-function-reference-base64.html """ return base64.b64encode(data) def handle_update(self): raise NotImplementedError("Update not implemented for Resource %s" % type(self)) def metadata_update(self, metadata): """ No-op for resources which don't explicitly override this method """ logger.warning("Resource %s does not implement metadata update" % self.name)
class InstanceGroup(stack_resource.StackResource): PROPERTIES = ( AVAILABILITY_ZONES, LAUNCH_CONFIGURATION_NAME, SIZE, LOAD_BALANCER_NAMES, TAGS, ) = ( 'AvailabilityZones', 'LaunchConfigurationName', 'Size', 'LoadBalancerNames', 'Tags', ) _TAG_KEYS = ( TAG_KEY, TAG_VALUE, ) = ( 'Key', 'Value', ) _ROLLING_UPDATE_SCHEMA_KEYS = (MIN_INSTANCES_IN_SERVICE, MAX_BATCH_SIZE, PAUSE_TIME) = ('MinInstancesInService', 'MaxBatchSize', 'PauseTime') _UPDATE_POLICY_SCHEMA_KEYS = (ROLLING_UPDATE, ) = ('RollingUpdate', ) properties_schema = { AVAILABILITY_ZONES: properties.Schema(properties.Schema.LIST, _('Not Implemented.'), required=True), LAUNCH_CONFIGURATION_NAME: properties.Schema(properties.Schema.STRING, _('Name of LaunchConfiguration resource.'), required=True, update_allowed=True), SIZE: properties.Schema(properties.Schema.INTEGER, _('Desired number of instances.'), required=True, update_allowed=True), LOAD_BALANCER_NAMES: properties.Schema(properties.Schema.LIST, _('List of LoadBalancer resources.')), TAGS: properties.Schema(properties.Schema.LIST, _('Tags to attach to this group.'), schema=properties.Schema( properties.Schema.MAP, schema={ TAG_KEY: properties.Schema(properties.Schema.STRING, required=True), TAG_VALUE: properties.Schema(properties.Schema.STRING, required=True), }, )), } attributes_schema = { "InstanceList": _("A comma-delimited list of server ip addresses. " "(Heat extension).") } rolling_update_schema = { MIN_INSTANCES_IN_SERVICE: properties.Schema(properties.Schema.NUMBER, default=0), MAX_BATCH_SIZE: properties.Schema(properties.Schema.NUMBER, default=1), PAUSE_TIME: properties.Schema(properties.Schema.STRING, default='PT0S') } update_policy_schema = { ROLLING_UPDATE: properties.Schema(properties.Schema.MAP, schema=rolling_update_schema) } def __init__(self, name, json_snippet, stack): """ UpdatePolicy is currently only specific to InstanceGroup and AutoScalingGroup. Therefore, init is overridden to parse for the UpdatePolicy. """ super(InstanceGroup, self).__init__(name, json_snippet, stack) self.update_policy = Properties(self.update_policy_schema, self.t.get('UpdatePolicy', {}), parent_name=self.name, context=self.context) def validate(self): """ Add validation for update_policy """ super(InstanceGroup, self).validate() if self.update_policy: self.update_policy.validate() policy_name = self.update_policy_schema.keys()[0] if self.update_policy[policy_name]: pause_time = self.update_policy[policy_name][self.PAUSE_TIME] if iso8601utils.parse_isoduration(pause_time) > 3600: raise ValueError('Maximum PauseTime is 1 hour.') def get_instance_names(self): """Get a list of resource names of the instances in this InstanceGroup. Failed resources will be ignored. """ return [r.name for r in self.get_instances()] def get_instances(self): """Get a list of all the instance resources managed by this group. Sort the list of instances first by created_time then by name. """ resources = [] if self.nested(): resources = [ resource for resource in self.nested().itervalues() if resource.status != resource.FAILED ] return sorted(resources, key=lambda r: (r.created_time, r.name)) def _environment(self): """Return the environment for the nested stack.""" return { environment.PARAMETERS: {}, environment.RESOURCE_REGISTRY: { SCALED_RESOURCE_TYPE: 'AWS::EC2::Instance', }, } def handle_create(self): """Create a nested stack and add the initial resources to it.""" num_instances = self.properties[self.SIZE] initial_template = self._create_template(num_instances) return self.create_with_template(initial_template, self._environment()) def check_create_complete(self, task): """ When stack creation is done, update the load balancer. If any instances failed to be created, delete them. """ done = super(InstanceGroup, self).check_create_complete(task) if done: self._lb_reload() return done def handle_update(self, json_snippet, tmpl_diff, prop_diff): """ If Properties has changed, update self.properties, so we get the new values during any subsequent adjustment. """ if tmpl_diff: # parse update policy if 'UpdatePolicy' in tmpl_diff: self.update_policy = Properties(self.update_policy_schema, json_snippet.get( 'UpdatePolicy', {}), parent_name=self.name, context=self.context) if prop_diff: self.properties = Properties(self.properties_schema, json_snippet.get('Properties', {}), function.resolve, self.name, self.context) # Replace instances first if launch configuration has changed self._try_rolling_update(prop_diff) # Get the current capacity, we may need to adjust if # Size has changed if self.SIZE in prop_diff: inst_list = self.get_instances() if len(inst_list) != self.properties[self.SIZE]: self.resize(self.properties[self.SIZE]) def _tags(self): """ Make sure that we add a tag that Ceilometer can pick up. These need to be prepended with 'metering.'. """ tags = self.properties.get(self.TAGS) or [] for t in tags: if t[self.TAG_KEY].startswith('metering.'): # the user has added one, don't add another. return tags return tags + [{ self.TAG_KEY: 'metering.groupname', self.TAG_VALUE: self.FnGetRefId() }] def handle_delete(self): return self.delete_nested() def _get_instance_definition(self): conf_name = self.properties[self.LAUNCH_CONFIGURATION_NAME] conf = self.stack.resource_by_refid(conf_name) instance_definition = function.resolve(conf.t) instance_definition['Type'] = SCALED_RESOURCE_TYPE instance_definition['Properties']['Tags'] = self._tags() if self.properties.get('VPCZoneIdentifier'): instance_definition['Properties']['SubnetId'] = \ self.properties['VPCZoneIdentifier'][0] return instance_definition def _get_instance_templates(self): """Get templates for resource instances.""" return [(instance.name, instance.t) for instance in self.get_instances()] def _create_template(self, num_instances, num_replace=0): """ Create a template to represent autoscaled instances. Also see heat.scaling.template.resource_templates. """ instance_definition = self._get_instance_definition() old_resources = self._get_instance_templates() templates = template.resource_templates(old_resources, instance_definition, num_instances, num_replace) return { "HeatTemplateFormatVersion": "2012-12-12", "Resources": dict(templates) } def _try_rolling_update(self, prop_diff): if (self.update_policy[self.ROLLING_UPDATE] and self.LAUNCH_CONFIGURATION_NAME in prop_diff): policy = self.update_policy[self.ROLLING_UPDATE] pause_sec = iso8601utils.parse_isoduration(policy[self.PAUSE_TIME]) self._replace(policy[self.MIN_INSTANCES_IN_SERVICE], policy[self.MAX_BATCH_SIZE], pause_sec) def _replace(self, min_in_service, batch_size, pause_sec): """ Replace the instances in the group using updated launch configuration """ def changing_instances(tmpl): def serialize_template(t): return json.dumps(function.resolve(t), sort_keys=True) instances = self.get_instances() # To support both HOT and CFN, need to find out what the name of # the resources key is. resources_key = self.nested().t.RESOURCES current = set((i.name, serialize_template(i.t)) for i in instances) updated = set((k, serialize_template(v)) for k, v in tmpl[resources_key].items()) # includes instances to be updated and deleted affected = set(k for k, v in current ^ updated) return set(i.FnGetRefId() for i in instances if i.name in affected) def pause_between_batch(): while True: try: yield except scheduler.Timeout: return capacity = len(self.nested()) if self.nested() else 0 efft_bat_sz = min(batch_size, capacity) efft_min_sz = min(min_in_service, capacity) batch_cnt = (capacity + efft_bat_sz - 1) // efft_bat_sz if pause_sec * (batch_cnt - 1) >= self.stack.timeout_secs(): raise ValueError('The current UpdatePolicy will result ' 'in stack update timeout.') # effective capacity includes temporary capacity added to accommodate # the minimum number of instances in service during update efft_capacity = max(capacity - efft_bat_sz, efft_min_sz) + efft_bat_sz try: remainder = capacity while remainder > 0 or efft_capacity > capacity: if capacity - remainder >= efft_min_sz: efft_capacity = capacity template = self._create_template(efft_capacity, efft_bat_sz) self._lb_reload(exclude=changing_instances(template)) updater = self.update_with_template(template, self._environment()) updater.run_to_completion() self.check_update_complete(updater) remainder -= efft_bat_sz if remainder > 0 and pause_sec > 0: self._lb_reload() waiter = scheduler.TaskRunner(pause_between_batch) waiter(timeout=pause_sec) finally: self._lb_reload() def resize(self, new_capacity): """ Resize the instance group to the new capacity. When shrinking, the oldest instances will be removed. """ new_template = self._create_template(new_capacity) try: updater = self.update_with_template(new_template, self._environment()) updater.run_to_completion() self.check_update_complete(updater) finally: # Reload the LB in any case, so it's only pointing at healthy # nodes. self._lb_reload() def _lb_reload(self, exclude=[]): ''' Notify the LoadBalancer to reload its config to include the changes in instances we have just made. This must be done after activation (instance in ACTIVE state), otherwise the instances' IP addresses may not be available. ''' if self.properties[self.LOAD_BALANCER_NAMES]: id_list = [ inst.FnGetRefId() for inst in self.get_instances() if inst.FnGetRefId() not in exclude ] for lb in self.properties[self.LOAD_BALANCER_NAMES]: lb_resource = self.stack[lb] lb_defn = copy.deepcopy(lb_resource.t) if 'Instances' in lb_resource.properties_schema: lb_defn['Properties']['Instances'] = id_list elif 'members' in lb_resource.properties_schema: lb_defn['Properties']['members'] = id_list else: raise exception.Error( _("Unsupported resource '%s' in LoadBalancerNames") % (lb, )) resolved_snippet = self.stack.resolve_static_data(lb_defn) scheduler.TaskRunner(lb_resource.update, resolved_snippet)() def FnGetRefId(self): return self.physical_resource_name() def _resolve_attribute(self, name): ''' heat extension: "InstanceList" returns comma delimited list of server ip addresses. ''' if name == 'InstanceList': return u','.join( inst.FnGetAtt('PublicIp') for inst in self.get_instances()) or None def child_template(self): num_instances = int(self.properties[self.SIZE]) return self._create_template(num_instances) def child_params(self): return self._environment()
class Resource(object): # Status strings CREATE_IN_PROGRESS = 'IN_PROGRESS' CREATE_FAILED = 'CREATE_FAILED' CREATE_COMPLETE = 'CREATE_COMPLETE' DELETE_IN_PROGRESS = 'DELETE_IN_PROGRESS' DELETE_FAILED = 'DELETE_FAILED' DELETE_COMPLETE = 'DELETE_COMPLETE' UPDATE_IN_PROGRESS = 'UPDATE_IN_PROGRESS' UPDATE_FAILED = 'UPDATE_FAILED' UPDATE_COMPLETE = 'UPDATE_COMPLETE' # If True, this resource must be created before it can be referenced. strict_dependency = True created_time = timestamp.Timestamp(db_api.resource_get, 'created_at') updated_time = timestamp.Timestamp(db_api.resource_get, 'updated_at') metadata = Metadata() # Resource implementation set this to the subset of template keys # which are supported for handle_update, used by update_template_diff update_allowed_keys = () # Resource implementation set this to the subset of resource properties # supported for handle_update, used by update_template_diff_properties update_allowed_properties = () def __new__(cls, name, json, stack): '''Create a new Resource of the appropriate class for its type.''' if cls != Resource: # Call is already for a subclass, so pass it through return super(Resource, cls).__new__(cls) # Select the correct subclass to instantiate ResourceClass = get_class(json['Type']) return ResourceClass(name, json, stack) def __init__(self, name, json_snippet, stack): if '/' in name: raise ValueError(_('Resource name may not contain "/"')) self.stack = stack self.context = stack.context self.name = name self.json_snippet = json_snippet self.t = stack.resolve_static_data(json_snippet) self.cached_t = None self.properties = Properties(self.properties_schema, self.t.get('Properties', {}), self.stack.resolve_runtime_data, self.name) resource = db_api.resource_get_by_name_and_stack( self.context, name, stack.id) if resource: self.resource_id = resource.nova_instance self.state = resource.state self.state_description = resource.state_description self.id = resource.id else: self.resource_id = None self.state = None self.state_description = '' self.id = None def __eq__(self, other): '''Allow == comparison of two resources.''' # For the purposes of comparison, we declare two resource objects # equal if their names and parsed_templates are the same if isinstance(other, Resource): return (self.name == other.name) and (self.parsed_template() == other.parsed_template()) return NotImplemented def __ne__(self, other): '''Allow != comparison of two resources.''' result = self.__eq__(other) if result is NotImplemented: return result return not result def type(self): return self.t['Type'] def identifier(self): '''Return an identifier for this resource.''' return identifier.ResourceIdentifier(resource_name=self.name, **self.stack.identifier()) def parsed_template(self, section=None, default={}, cached=False): ''' Return the parsed template data for the resource. May be limited to only one section of the data, in which case a default value may also be supplied. ''' if cached and self.cached_t: t = self.cached_t else: t = self.t if section is None: template = t else: template = t.get(section, default) return self.stack.resolve_runtime_data(template) def cache_template(self): ''' make a cache of the resource's parsed template this can then be used via parsed_template(cached=True) ''' self.cached_t = self.stack.resolve_runtime_data(self.t) def update_template_diff(self, json_snippet=None): ''' Returns the difference between json_template and self.t If something has been removed in json_snippet which exists in self.t we set it to None. If any keys have changed which are not in update_allowed_keys, raises UpdateReplace if the differing keys are not in update_allowed_keys ''' update_allowed_set = set(self.update_allowed_keys) # Create a set containing the keys in both current and update template current_template = self.parsed_template(cached=True) template_keys = set(current_template.keys()) new_template = self.stack.resolve_runtime_data(json_snippet) template_keys.update(set(new_template.keys())) # Create a set of keys which differ (or are missing/added) changed_keys_set = set([ k for k in template_keys if current_template.get(k) != new_template.get(k) ]) if not changed_keys_set.issubset(update_allowed_set): badkeys = changed_keys_set - update_allowed_set raise UpdateReplace(self.name) return dict((k, new_template.get(k)) for k in changed_keys_set) def update_template_diff_properties(self, json_snippet=None): ''' Returns the changed Properties between json_template and self.t If a property has been removed in json_snippet which exists in self.t we set it to None. If any properties have changed which are not in update_allowed_properties, raises UpdateReplace if the modified properties are not in the update_allowed_properties ''' update_allowed_set = set(self.update_allowed_properties) # Create a set containing the keys in both current and update template tmpl = self.parsed_template(cached=True) current_properties = tmpl.get('Properties', {}) template_properties = set(current_properties.keys()) updated_properties = json_snippet.get('Properties', {}) template_properties.update(set(updated_properties.keys())) # Create a set of keys which differ (or are missing/added) changed_properties_set = set( k for k in template_properties if current_properties.get(k) != updated_properties.get(k)) if not changed_properties_set.issubset(update_allowed_set): raise UpdateReplace(self.name) return dict( (k, updated_properties.get(k)) for k in changed_properties_set) def __str__(self): return '%s "%s"' % (self.__class__.__name__, self.name) def _add_dependencies(self, deps, head, fragment): if isinstance(fragment, dict): for key, value in fragment.items(): if key in ('DependsOn', 'Ref', 'Fn::GetAtt'): if key == 'Fn::GetAtt': value, head = value try: target = self.stack.resources[value] except KeyError: raise exception.InvalidTemplateReference( resource=value, key=head) if key == 'DependsOn' or target.strict_dependency: deps += (self, target) else: self._add_dependencies(deps, key, value) elif isinstance(fragment, list): for item in fragment: self._add_dependencies(deps, head, item) def add_dependencies(self, deps): self._add_dependencies(deps, None, self.t) deps += (self, None) def keystone(self): return self.stack.clients.keystone() def nova(self, service_type='compute'): return self.stack.clients.nova(service_type) def swift(self): return self.stack.clients.swift() def quantum(self): return self.stack.clients.quantum() def cinder(self): return self.stack.clients.cinder() def create(self): ''' Create the resource. Subclasses should provide a handle_create() method to customise creation. ''' assert self.state is None, 'Resource create requested in invalid state' logger.info('creating %s' % str(self)) # Re-resolve the template, since if the resource Ref's # the AWS::StackId pseudo parameter, it will change after # the parser.Stack is stored (which is after the resources # are __init__'d, but before they are create()'d) self.t = self.stack.resolve_static_data(self.json_snippet) self.properties = Properties(self.properties_schema, self.t.get('Properties', {}), self.stack.resolve_runtime_data, self.name) try: self.properties.validate() self.state_set(self.CREATE_IN_PROGRESS) create_data = None if callable(getattr(self, 'handle_create', None)): create_data = self.handle_create() yield while not self.check_create_complete(create_data): yield except greenlet.GreenletExit: # Older versions of greenlet erroneously had GreenletExit inherit # from Exception instead of BaseException with excutils.save_and_reraise_exception(): try: self.state_set(self.CREATE_FAILED, 'Creation aborted') except Exception: logger.exception('Error marking resource as failed') except Exception as ex: logger.exception('create %s', str(self)) failure = exception.ResourceFailure(ex) self.state_set(self.CREATE_FAILED, str(failure)) raise failure except: with excutils.save_and_reraise_exception(): try: self.state_set(self.CREATE_FAILED, 'Creation aborted') except Exception: logger.exception('Error marking resource as failed') else: self.state_set(self.CREATE_COMPLETE) def check_create_complete(self, create_data): ''' Check if the resource is active (ready to move to the CREATE_COMPLETE state). By default this happens as soon as the handle_create() method has completed successfully, but subclasses may customise this by overriding this function. The return value of handle_create() is passed in to this function each time it is called. ''' return True def update(self, json_snippet=None): ''' update the resource. Subclasses should provide a handle_update() method to customise update, the base-class handle_update will fail by default. ''' assert json_snippet is not None, 'Must specify update json snippet' if self.state in (self.CREATE_IN_PROGRESS, self.UPDATE_IN_PROGRESS): raise exception.ResourceFailure( Exception('Resource update already requested')) logger.info('updating %s' % str(self)) try: self.state_set(self.UPDATE_IN_PROGRESS) properties = Properties(self.properties_schema, json_snippet.get('Properties', {}), self.stack.resolve_runtime_data, self.name) properties.validate() tmpl_diff = self.update_template_diff(json_snippet) prop_diff = self.update_template_diff_properties(json_snippet) if callable(getattr(self, 'handle_update', None)): result = self.handle_update(json_snippet, tmpl_diff, prop_diff) except UpdateReplace: logger.debug("Resource %s update requires replacement" % self.name) raise except Exception as ex: logger.exception('update %s : %s' % (str(self), str(ex))) failure = exception.ResourceFailure(ex) self.state_set(self.UPDATE_FAILED, str(failure)) raise failure else: self.t = self.stack.resolve_static_data(json_snippet) self.state_set(self.UPDATE_COMPLETE) def physical_resource_name(self): return '%s-%s' % (self.stack.name, self.name) def validate(self): logger.info('Validating %s' % str(self)) self.validate_deletion_policy(self.t) return self.properties.validate() @classmethod def validate_deletion_policy(cls, template): deletion_policy = template.get('DeletionPolicy', 'Delete') if deletion_policy not in ('Delete', 'Retain', 'Snapshot'): msg = 'Invalid DeletionPolicy %s' % deletion_policy raise exception.StackValidationFailed(message=msg) elif deletion_policy == 'Snapshot': if not callable(getattr(cls, 'handle_snapshot_delete', None)): msg = 'Snapshot DeletionPolicy not supported' raise exception.StackValidationFailed(message=msg) def delete(self): ''' Delete the resource. Subclasses should provide a handle_delete() method to customise deletion. ''' if self.state == self.DELETE_COMPLETE: return if self.state == self.DELETE_IN_PROGRESS: raise exception.Error('Resource deletion already in progress') # No need to delete if the resource has never been created if self.state is None: return initial_state = self.state logger.info('deleting %s' % str(self)) try: self.state_set(self.DELETE_IN_PROGRESS) deletion_policy = self.t.get('DeletionPolicy', 'Delete') if deletion_policy == 'Delete': if callable(getattr(self, 'handle_delete', None)): self.handle_delete() elif deletion_policy == 'Snapshot': if callable(getattr(self, 'handle_snapshot_delete', None)): self.handle_snapshot_delete(initial_state) except Exception as ex: logger.exception('Delete %s', str(self)) failure = exception.ResourceFailure(ex) self.state_set(self.DELETE_FAILED, str(failure)) raise failure except: with excutils.save_and_reraise_exception(): try: self.state_set(self.DELETE_FAILED, 'Deletion aborted') except Exception: logger.exception('Error marking resource deletion failed') else: self.state_set(self.DELETE_COMPLETE) def destroy(self): ''' Delete the resource and remove it from the database. ''' self.delete() if self.id is None: return try: db_api.resource_get(self.context, self.id).delete() except exception.NotFound: # Don't fail on delete if the db entry has # not been created yet. pass self.id = None def resource_id_set(self, inst): self.resource_id = inst if self.id is not None: try: rs = db_api.resource_get(self.context, self.id) rs.update_and_save({'nova_instance': self.resource_id}) except Exception as ex: logger.warn('db error %s' % str(ex)) def _store(self): '''Create the resource in the database.''' try: rs = { 'state': self.state, 'stack_id': self.stack.id, 'nova_instance': self.resource_id, 'name': self.name, 'rsrc_metadata': self.metadata, 'stack_name': self.stack.name } new_rs = db_api.resource_create(self.context, rs) self.id = new_rs.id self.stack.updated_time = datetime.utcnow() except Exception as ex: logger.error('DB error %s' % str(ex)) def _add_event(self, new_state, reason): '''Add a state change event to the database.''' ev = event.Event(self.context, self.stack, self, new_state, reason, self.resource_id, self.properties) try: ev.store() except Exception as ex: logger.error('DB error %s' % str(ex)) def _store_or_update(self, new_state, reason): self.state = new_state self.state_description = reason if self.id is not None: try: rs = db_api.resource_get(self.context, self.id) rs.update_and_save({ 'state': self.state, 'state_description': reason, 'nova_instance': self.resource_id }) self.stack.updated_time = datetime.utcnow() except Exception as ex: logger.error('DB error %s' % str(ex)) # store resource in DB on transition to CREATE_IN_PROGRESS # all other transistions (other than to DELETE_COMPLETE) # should be handled by the update_and_save above.. elif new_state == self.CREATE_IN_PROGRESS: self._store() def state_set(self, new_state, reason="state changed"): old_state = self.state self._store_or_update(new_state, reason) if new_state != old_state: self._add_event(new_state, reason) def FnGetRefId(self): ''' http://docs.amazonwebservices.com/AWSCloudFormation/latest/UserGuide/\ intrinsic-function-reference-ref.html ''' if self.resource_id is not None: return unicode(self.resource_id) else: return unicode(self.name) def FnGetAtt(self, key): ''' http://docs.amazonwebservices.com/AWSCloudFormation/latest/UserGuide/\ intrinsic-function-reference-getatt.html ''' return unicode(self.name) def FnBase64(self, data): ''' http://docs.amazonwebservices.com/AWSCloudFormation/latest/UserGuide/\ intrinsic-function-reference-base64.html ''' return base64.b64encode(data) def handle_update(self, json_snippet=None, tmpl_diff=None, prop_diff=None): raise UpdateReplace(self.name) def metadata_update(self, new_metadata=None): ''' No-op for resources which don't explicitly override this method ''' if new_metadata: logger.warning("Resource %s does not implement metadata update" % self.name)
class Resource(object): ACTIONS = (INIT, CREATE, DELETE, UPDATE, ROLLBACK, SUSPEND, RESUME) = ('INIT', 'CREATE', 'DELETE', 'UPDATE', 'ROLLBACK', 'SUSPEND', 'RESUME') STATUSES = (IN_PROGRESS, FAILED, COMPLETE) = ('IN_PROGRESS', 'FAILED', 'COMPLETE') # If True, this resource must be created before it can be referenced. strict_dependency = True created_time = timestamp.Timestamp(db_api.resource_get, 'created_at') updated_time = timestamp.Timestamp(db_api.resource_get, 'updated_at') metadata = Metadata() # Resource implementation set this to the subset of template keys # which are supported for handle_update, used by update_template_diff update_allowed_keys = () # Resource implementation set this to the subset of resource properties # supported for handle_update, used by update_template_diff_properties update_allowed_properties = () # Resource implementations set this to the name: description dictionary # that describes the appropriate resource attributes attributes_schema = {} def __new__(cls, name, json, stack): '''Create a new Resource of the appropriate class for its type.''' if cls != Resource: # Call is already for a subclass, so pass it through return super(Resource, cls).__new__(cls) # Select the correct subclass to instantiate ResourceClass = stack.env.get_class(json['Type'], resource_name=name) return ResourceClass(name, json, stack) def __init__(self, name, json_snippet, stack): if '/' in name: raise ValueError(_('Resource name may not contain "/"')) self.stack = stack self.context = stack.context self.name = name self.json_snippet = json_snippet self.t = stack.resolve_static_data(json_snippet) self.properties = Properties(self.properties_schema, self.t.get('Properties', {}), self._resolve_runtime_data, self.name) self.attributes = Attributes(self.name, self.attributes_schema, self._resolve_attribute) resource = db_api.resource_get_by_name_and_stack( self.context, name, stack.id) if resource: self.resource_id = resource.nova_instance self.action = resource.action self.status = resource.status self.status_reason = resource.status_reason self.id = resource.id self.data = resource.data else: self.resource_id = None # if the stack is being deleted, assume we've already been deleted if stack.action == stack.DELETE: self.action = self.DELETE else: self.action = self.INIT self.status = self.COMPLETE self.status_reason = '' self.id = None self.data = [] def __eq__(self, other): '''Allow == comparison of two resources.''' # For the purposes of comparison, we declare two resource objects # equal if their names and parsed_templates are the same if isinstance(other, Resource): return (self.name == other.name) and (self.parsed_template() == other.parsed_template()) return NotImplemented def __ne__(self, other): '''Allow != comparison of two resources.''' result = self.__eq__(other) if result is NotImplemented: return result return not result def type(self): return self.t['Type'] def _resolve_runtime_data(self, snippet): return self.stack.resolve_runtime_data(snippet) def has_interface(self, resource_type): """Check to see if this resource is either mapped to resource_type or is a "resource_type". """ if self.type() == resource_type: return True ri = self.stack.env.get_resource_info(self.type(), self.name) return ri.name == resource_type def identifier(self): '''Return an identifier for this resource.''' return identifier.ResourceIdentifier(resource_name=self.name, **self.stack.identifier()) def parsed_template(self, section=None, default={}): ''' Return the parsed template data for the resource. May be limited to only one section of the data, in which case a default value may also be supplied. ''' if section is None: template = self.t else: template = self.t.get(section, default) return self._resolve_runtime_data(template) def update_template_diff(self, after, before): ''' Returns the difference between the before and after json snippets. If something has been removed in after which exists in before we set it to None. If any keys have changed which are not in update_allowed_keys, raises UpdateReplace if the differing keys are not in update_allowed_keys ''' update_allowed_set = set(self.update_allowed_keys) # Create a set containing the keys in both current and update template template_keys = set(before.keys()) template_keys.update(set(after.keys())) # Create a set of keys which differ (or are missing/added) changed_keys_set = set( [k for k in template_keys if before.get(k) != after.get(k)]) if not changed_keys_set.issubset(update_allowed_set): badkeys = changed_keys_set - update_allowed_set raise UpdateReplace(self.name) return dict((k, after.get(k)) for k in changed_keys_set) def update_template_diff_properties(self, after, before): ''' Returns the changed Properties between the before and after json snippets. If a property has been removed in after which exists in before we set it to None. If any properties have changed which are not in update_allowed_properties, raises UpdateReplace if the modified properties are not in the update_allowed_properties ''' update_allowed_set = set(self.update_allowed_properties) # Create a set containing the keys in both current and update template current_properties = before.get('Properties', {}) template_properties = set(current_properties.keys()) updated_properties = after.get('Properties', {}) template_properties.update(set(updated_properties.keys())) # Create a set of keys which differ (or are missing/added) changed_properties_set = set( k for k in template_properties if current_properties.get(k) != updated_properties.get(k)) if not changed_properties_set.issubset(update_allowed_set): raise UpdateReplace(self.name) return dict( (k, updated_properties.get(k)) for k in changed_properties_set) def __str__(self): return '%s "%s"' % (self.__class__.__name__, self.name) def _add_dependencies(self, deps, head, fragment): if isinstance(fragment, dict): for key, value in fragment.items(): if key in ('DependsOn', 'Ref', 'Fn::GetAtt'): if key == 'Fn::GetAtt': value, head = value try: target = self.stack.resources[value] except KeyError: raise exception.InvalidTemplateReference( resource=value, key=head) if key == 'DependsOn' or target.strict_dependency: deps += (self, target) else: self._add_dependencies(deps, key, value) elif isinstance(fragment, list): for item in fragment: self._add_dependencies(deps, head, item) def add_dependencies(self, deps): self._add_dependencies(deps, None, self.t) deps += (self, None) def required_by(self): ''' Returns a list of names of resources which directly require this resource as a dependency. ''' return list( [r.name for r in self.stack.dependencies.required_by(self)]) def keystone(self): return self.stack.clients.keystone() def nova(self, service_type='compute'): return self.stack.clients.nova(service_type) def swift(self): return self.stack.clients.swift() def neutron(self): return self.stack.clients.neutron() def cinder(self): return self.stack.clients.cinder() def ceilometer(self): return self.stack.clients.ceilometer() def _do_action(self, action, pre_func=None): ''' Perform a transition to a new state via a specified action action should be e.g self.CREATE, self.UPDATE etc, we set status based on this, the transistion is handled by calling the corresponding handle_* and check_*_complete functions Note pre_func is an optional function reference which will be called before the handle_<action> function If the resource does not declare a check_$action_complete function, we declare COMPLETE status as soon as the handle_$action call has finished, and if no handle_$action function is declared, then we do nothing, useful e.g if the resource requires no action for a given state transition ''' assert action in self.ACTIONS, 'Invalid action %s' % action try: self.state_set(action, self.IN_PROGRESS) action_l = action.lower() handle = getattr(self, 'handle_%s' % action_l, None) check = getattr(self, 'check_%s_complete' % action_l, None) if callable(pre_func): pre_func() handle_data = None if callable(handle): handle_data = handle() yield if callable(check): while not check(handle_data): yield except Exception as ex: logger.exception('%s : %s' % (action, str(self))) failure = exception.ResourceFailure(ex, self, action) self.state_set(action, self.FAILED, str(failure)) raise failure except: with excutils.save_and_reraise_exception(): try: self.state_set(action, self.FAILED, '%s aborted' % action) except Exception: logger.exception('Error marking resource as failed') else: self.state_set(action, self.COMPLETE) def create(self): ''' Create the resource. Subclasses should provide a handle_create() method to customise creation. ''' action = self.CREATE if (self.action, self.status) != (self.INIT, self.COMPLETE): exc = exception.Error('State %s invalid for create' % str(self.state)) raise exception.ResourceFailure(exc, self, action) logger.info('creating %s' % str(self)) # Re-resolve the template, since if the resource Ref's # the AWS::StackId pseudo parameter, it will change after # the parser.Stack is stored (which is after the resources # are __init__'d, but before they are create()'d) self.t = self.stack.resolve_static_data(self.json_snippet) self.properties = Properties(self.properties_schema, self.t.get('Properties', {}), self._resolve_runtime_data, self.name) return self._do_action(action, self.properties.validate) def update(self, after, before=None): ''' update the resource. Subclasses should provide a handle_update() method to customise update, the base-class handle_update will fail by default. ''' action = self.UPDATE if before is None: before = self.parsed_template() if (self.action, self.status) in ((self.CREATE, self.IN_PROGRESS), (self.UPDATE, self.IN_PROGRESS)): exc = Exception('Resource update already requested') raise exception.ResourceFailure(exc, self, action) logger.info('updating %s' % str(self)) try: self.state_set(action, self.IN_PROGRESS) properties = Properties(self.properties_schema, after.get('Properties', {}), self._resolve_runtime_data, self.name) properties.validate() tmpl_diff = self.update_template_diff(after, before) prop_diff = self.update_template_diff_properties(after, before) if callable(getattr(self, 'handle_update', None)): result = self.handle_update(after, tmpl_diff, prop_diff) except UpdateReplace: logger.debug("Resource %s update requires replacement" % self.name) raise except Exception as ex: logger.exception('update %s : %s' % (str(self), str(ex))) failure = exception.ResourceFailure(ex, self, action) self.state_set(action, self.FAILED, str(failure)) raise failure else: self.t = self.stack.resolve_static_data(after) self.state_set(action, self.COMPLETE) def suspend(self): ''' Suspend the resource. Subclasses should provide a handle_suspend() method to implement suspend ''' action = self.SUSPEND # Don't try to suspend the resource unless it's in a stable state if (self.action == self.DELETE or self.status != self.COMPLETE): exc = exception.Error('State %s invalid for suspend' % str(self.state)) raise exception.ResourceFailure(exc, self, action) logger.info('suspending %s' % str(self)) return self._do_action(action) def resume(self): ''' Resume the resource. Subclasses should provide a handle_resume() method to implement resume ''' action = self.RESUME # Can't resume a resource unless it's SUSPEND_COMPLETE if self.state != (self.SUSPEND, self.COMPLETE): exc = exception.Error('State %s invalid for resume' % str(self.state)) raise exception.ResourceFailure(exc, self, action) logger.info('resuming %s' % str(self)) return self._do_action(action) def physical_resource_name(self): if self.id is None: return None return '%s-%s-%s' % (self.stack.name, self.name, short_id.get_id(self.id)) def validate(self): logger.info('Validating %s' % str(self)) self.validate_deletion_policy(self.t) return self.properties.validate() @classmethod def validate_deletion_policy(cls, template): deletion_policy = template.get('DeletionPolicy', 'Delete') if deletion_policy not in ('Delete', 'Retain', 'Snapshot'): msg = 'Invalid DeletionPolicy %s' % deletion_policy raise exception.StackValidationFailed(message=msg) elif deletion_policy == 'Snapshot': if not callable(getattr(cls, 'handle_snapshot_delete', None)): msg = 'Snapshot DeletionPolicy not supported' raise exception.StackValidationFailed(message=msg) def delete(self): ''' Delete the resource. Subclasses should provide a handle_delete() method to customise deletion. ''' action = self.DELETE if (self.action, self.status) == (self.DELETE, self.COMPLETE): return # No need to delete if the resource has never been created if self.action == self.INIT: return initial_state = self.state logger.info('deleting %s' % str(self)) try: self.state_set(action, self.IN_PROGRESS) deletion_policy = self.t.get('DeletionPolicy', 'Delete') if deletion_policy == 'Delete': if callable(getattr(self, 'handle_delete', None)): self.handle_delete() elif deletion_policy == 'Snapshot': if callable(getattr(self, 'handle_snapshot_delete', None)): self.handle_snapshot_delete(initial_state) except Exception as ex: logger.exception('Delete %s', str(self)) failure = exception.ResourceFailure(ex, self, self.action) self.state_set(action, self.FAILED, str(failure)) raise failure except: with excutils.save_and_reraise_exception(): try: self.state_set(action, self.FAILED, 'Deletion aborted') except Exception: logger.exception('Error marking resource deletion failed') else: self.state_set(action, self.COMPLETE) def destroy(self): ''' Delete the resource and remove it from the database. ''' self.delete() if self.id is None: return try: db_api.resource_get(self.context, self.id).delete() except exception.NotFound: # Don't fail on delete if the db entry has # not been created yet. pass self.id = None def resource_id_set(self, inst): self.resource_id = inst if self.id is not None: try: rs = db_api.resource_get(self.context, self.id) rs.update_and_save({'nova_instance': self.resource_id}) except Exception as ex: logger.warn('db error %s' % str(ex)) def _store(self): '''Create the resource in the database.''' metadata = self.metadata try: rs = { 'action': self.action, 'status': self.status, 'status_reason': self.status_reason, 'stack_id': self.stack.id, 'nova_instance': self.resource_id, 'name': self.name, 'rsrc_metadata': metadata, 'stack_name': self.stack.name } new_rs = db_api.resource_create(self.context, rs) self.id = new_rs.id self.stack.updated_time = datetime.utcnow() except Exception as ex: logger.error('DB error %s' % str(ex)) def _add_event(self, action, status, reason): '''Add a state change event to the database.''' ev = event.Event(self.context, self.stack, action, status, reason, self.resource_id, self.properties, self.name, self.type()) try: ev.store() except Exception as ex: logger.error('DB error %s' % str(ex)) def _store_or_update(self, action, status, reason): self.action = action self.status = status self.status_reason = reason if self.id is not None: try: rs = db_api.resource_get(self.context, self.id) rs.update_and_save({ 'action': self.action, 'status': self.status, 'status_reason': reason, 'stack_id': self.stack.id, 'nova_instance': self.resource_id }) self.stack.updated_time = datetime.utcnow() except Exception as ex: logger.error('DB error %s' % str(ex)) # store resource in DB on transition to CREATE_IN_PROGRESS # all other transistions (other than to DELETE_COMPLETE) # should be handled by the update_and_save above.. elif (action, status) == (self.CREATE, self.IN_PROGRESS): self._store() def _resolve_attribute(self, name): """ Default implementation; should be overridden by resources that expose attributes :param name: The attribute to resolve :returns: the resource attribute named key """ # By default, no attributes resolve pass def state_reset(self): """ Reset state to (INIT, COMPLETE) """ self.action = self.INIT self.status = self.COMPLETE def state_set(self, action, status, reason="state changed"): if action not in self.ACTIONS: raise ValueError("Invalid action %s" % action) if status not in self.STATUSES: raise ValueError("Invalid status %s" % status) old_state = (self.action, self.status) new_state = (action, status) self._store_or_update(action, status, reason) if new_state != old_state: self._add_event(action, status, reason) @property def state(self): '''Returns state, tuple of action, status.''' return (self.action, self.status) def FnGetRefId(self): ''' http://docs.amazonwebservices.com/AWSCloudFormation/latest/UserGuide/\ intrinsic-function-reference-ref.html ''' if self.resource_id is not None: return unicode(self.resource_id) else: return unicode(self.name) def FnGetAtt(self, key): ''' http://docs.amazonwebservices.com/AWSCloudFormation/latest/UserGuide/\ intrinsic-function-reference-getatt.html ''' try: return self.attributes[key] except KeyError: raise exception.InvalidTemplateAttribute(resource=self.name, key=key) def FnBase64(self, data): ''' http://docs.amazonwebservices.com/AWSCloudFormation/latest/UserGuide/\ intrinsic-function-reference-base64.html ''' return base64.b64encode(data) def signal(self, details=None): ''' signal the resource. Subclasses should provide a handle_signal() method to implement the signal, the base-class raise an exception if no handler is implemented. ''' try: if self.action in (self.SUSPEND, self.DELETE): msg = 'Cannot signal resource during %s' % self.action raise Exception(msg) if not callable(getattr(self, 'handle_signal', None)): msg = 'Resource %s is not able to receive a signal' % str(self) raise Exception(msg) self._add_event('signal', self.status, details) self.handle_signal(details) except Exception as ex: logger.exception('signal %s : %s' % (str(self), str(ex))) failure = exception.ResourceFailure(ex, self) raise failure def handle_update(self, json_snippet=None, tmpl_diff=None, prop_diff=None): raise UpdateReplace(self.name) def metadata_update(self, new_metadata=None): ''' No-op for resources which don't explicitly override this method ''' if new_metadata: logger.warning("Resource %s does not implement metadata update" % self.name) @classmethod def resource_to_template(cls, resource_type): ''' :param resource_type: The resource type to be displayed in the template :param explode_nested: True if a resource's nested properties schema should be resolved. :returns: A template where the resource's properties_schema is mapped as parameters, and the resource's attributes_schema is mapped as outputs ''' (parameters, properties) = (Properties.schema_to_parameters_and_properties( cls.properties_schema)) resource_name = cls.__name__ return { 'Parameters': parameters, 'Resources': { resource_name: { 'Type': resource_type, 'Properties': properties } }, 'Outputs': Attributes.as_outputs(resource_name, cls) }
class Resource(object): ACTIONS = (INIT, CREATE, DELETE, UPDATE, ROLLBACK, SUSPEND, RESUME, ADOPT ) = ('INIT', 'CREATE', 'DELETE', 'UPDATE', 'ROLLBACK', 'SUSPEND', 'RESUME', 'ADOPT') STATUSES = (IN_PROGRESS, FAILED, COMPLETE ) = ('IN_PROGRESS', 'FAILED', 'COMPLETE') # If True, this resource must be created before it can be referenced. strict_dependency = True # Resource implementation set this to the subset of resource properties # supported for handle_update, used by update_template_diff_properties update_allowed_properties = () # Resource implementations set this to the name: description dictionary # that describes the appropriate resource attributes attributes_schema = {} # If True, this resource may perform authenticated API requests # throughout its lifecycle requires_deferred_auth = False # Limit to apply to physical_resource_name() size reduction algorithm. # If set to None no limit will be applied. physical_resource_name_limit = 255 support_status = support.SupportStatus() def __new__(cls, name, json, stack): '''Create a new Resource of the appropriate class for its type.''' if cls != Resource: # Call is already for a subclass, so pass it through return super(Resource, cls).__new__(cls) # Select the correct subclass to instantiate ResourceClass = stack.env.get_class(json.get('Type'), resource_name=name) return ResourceClass(name, json, stack) def __init__(self, name, definition, stack): if '/' in name: raise ValueError(_('Resource name may not contain "/"')) self.stack = stack self.context = stack.context self.name = name if isinstance(definition, rsrc_defn.ResourceDefinition): self.t = definition else: self.t = self.stack.resolve_static_data(definition) self.reparse() self.attributes = Attributes(self.name, self.attributes_schema, self._resolve_attribute) self.abandon_in_progress = False resource = stack.db_resource_get(name) if resource: self.resource_id = resource.nova_instance self.action = resource.action self.status = resource.status self.status_reason = resource.status_reason self.id = resource.id try: self._data = db_api.resource_data_get_all(self, resource.data) except exception.NotFound: self._data = {} self._rsrc_metadata = resource.rsrc_metadata self.created_time = resource.created_at self.updated_time = resource.updated_at else: self.resource_id = None # if the stack is being deleted, assume we've already been deleted if stack.action == stack.DELETE: self.action = self.DELETE else: self.action = self.INIT self.status = self.COMPLETE self.status_reason = '' self.id = None self._data = {} self._rsrc_metadata = None self.created_time = None self.updated_time = None def reparse(self): self.properties = Properties(self.properties_schema, self.t.get('Properties', {}), function.resolve, self.name, self.context) def __eq__(self, other): '''Allow == comparison of two resources.''' # For the purposes of comparison, we declare two resource objects # equal if their names and parsed_templates are the same if isinstance(other, Resource): return (self.name == other.name) and ( self.parsed_template() == other.parsed_template()) return NotImplemented def __ne__(self, other): '''Allow != comparison of two resources.''' result = self.__eq__(other) if result is NotImplemented: return result return not result def metadata_get(self, refresh=False): if refresh: self._rsrc_metadata = None if self.id is None: return self.parsed_template('Metadata') if self._rsrc_metadata is not None: return self._rsrc_metadata rs = db_api.resource_get(self.stack.context, self.id) rs.refresh(attrs=['rsrc_metadata']) self._rsrc_metadata = rs.rsrc_metadata return rs.rsrc_metadata def metadata_set(self, metadata): if self.id is None: raise exception.ResourceNotAvailable(resource_name=self.name) rs = db_api.resource_get(self.stack.context, self.id) rs.update_and_save({'rsrc_metadata': metadata}) self._rsrc_metadata = metadata def type(self): return self.t['Type'] def has_interface(self, resource_type): """Check to see if this resource is either mapped to resource_type or is a "resource_type". """ if self.type() == resource_type: return True ri = self.stack.env.get_resource_info(self.type(), self.name) return ri.name == resource_type def implementation_signature(self): ''' Return a tuple defining the implementation. This should be broken down into a definition and an implementation version. ''' return (self.__class__.__name__, self.support_status.version) def identifier(self): '''Return an identifier for this resource.''' return identifier.ResourceIdentifier(resource_name=self.name, **self.stack.identifier()) def parsed_template(self, section=None, default={}): ''' Return the parsed template data for the resource. May be limited to only one section of the data, in which case a default value may also be supplied. ''' if section is None: template = self.t else: template = self.t.get(section, default) return function.resolve(template) def update_template_diff(self, after, before): ''' Returns the difference between the before and after json snippets. If something has been removed in after which exists in before we set it to None. ''' # Create a set containing the keys in both current and update template template_keys = set(before.keys()) template_keys.update(set(after.keys())) # Create a set of keys which differ (or are missing/added) changed_keys_set = set([k for k in template_keys if before.get(k) != after.get(k)]) return dict((k, after.get(k)) for k in changed_keys_set) def update_template_diff_properties(self, after_props, before_props): ''' Returns the changed Properties between the before and after properties. If any properties have changed which are not in update_allowed_properties, raises UpdateReplace. ''' update_allowed_set = set(self.update_allowed_properties) for (psk, psv) in self.properties.props.iteritems(): if psv.update_allowed(): update_allowed_set.add(psk) # Create a set of keys which differ (or are missing/added) changed_properties_set = set(k for k in after_props if before_props.get(k) != after_props.get(k)) if not changed_properties_set.issubset(update_allowed_set): raise UpdateReplace(self.name) return dict((k, after_props.get(k)) for k in changed_properties_set) def __str__(self): if self.stack.id: if self.resource_id: return '%s "%s" [%s] %s' % (self.__class__.__name__, self.name, self.resource_id, str(self.stack)) return '%s "%s" %s' % (self.__class__.__name__, self.name, str(self.stack)) return '%s "%s"' % (self.__class__.__name__, self.name) def add_dependencies(self, deps): for dep in self.t.dependencies(self.stack): deps += (self, dep) deps += (self, None) def required_by(self): ''' Returns a list of names of resources which directly require this resource as a dependency. ''' return list( [r.name for r in self.stack.dependencies.required_by(self)]) def keystone(self): return self.stack.clients.keystone() def nova(self, service_type='compute'): return self.stack.clients.nova(service_type) def swift(self): return self.stack.clients.swift() def neutron(self): return self.stack.clients.neutron() def cinder(self): return self.stack.clients.cinder() def trove(self): return self.stack.clients.trove() def ceilometer(self): return self.stack.clients.ceilometer() def heat(self): return self.stack.clients.heat() def glance(self): return self.stack.clients.glance() def _do_action(self, action, pre_func=None, resource_data=None): ''' Perform a transition to a new state via a specified action action should be e.g self.CREATE, self.UPDATE etc, we set status based on this, the transition is handled by calling the corresponding handle_* and check_*_complete functions Note pre_func is an optional function reference which will be called before the handle_<action> function If the resource does not declare a check_$action_complete function, we declare COMPLETE status as soon as the handle_$action call has finished, and if no handle_$action function is declared, then we do nothing, useful e.g if the resource requires no action for a given state transition ''' assert action in self.ACTIONS, 'Invalid action %s' % action try: self.state_set(action, self.IN_PROGRESS) action_l = action.lower() handle = getattr(self, 'handle_%s' % action_l, None) check = getattr(self, 'check_%s_complete' % action_l, None) if callable(pre_func): pre_func() handle_data = None if callable(handle): handle_data = (handle(resource_data) if resource_data else handle()) yield if callable(check): while not check(handle_data): yield except Exception as ex: LOG.exception('%s : %s' % (action, str(self))) # noqa failure = exception.ResourceFailure(ex, self, action) self.state_set(action, self.FAILED, six.text_type(failure)) raise failure except: with excutils.save_and_reraise_exception(): try: self.state_set(action, self.FAILED, '%s aborted' % action) except Exception: LOG.exception(_('Error marking resource as failed')) else: self.state_set(action, self.COMPLETE) def preview(self): ''' Default implementation of Resource.preview. This method should be overridden by child classes for specific behavior. ''' return self def create(self): ''' Create the resource. Subclasses should provide a handle_create() method to customise creation. ''' action = self.CREATE if (self.action, self.status) != (self.INIT, self.COMPLETE): exc = exception.Error(_('State %s invalid for create') % str(self.state)) raise exception.ResourceFailure(exc, self, action) LOG.info(_('creating %s') % str(self)) # Re-resolve the template, since if the resource Ref's # the StackId pseudo parameter, it will change after # the parser.Stack is stored (which is after the resources # are __init__'d, but before they are create()'d) self.reparse() return self._do_action(action, self.properties.validate) def prepare_abandon(self): self.abandon_in_progress = True return { 'name': self.name, 'resource_id': self.resource_id, 'type': self.type(), 'action': self.action, 'status': self.status, 'metadata': self.metadata_get(refresh=True), 'resource_data': self.data() } def adopt(self, resource_data): ''' Adopt the existing resource. Resource subclasses can provide a handle_adopt() method to customise adopt. ''' return self._do_action(self.ADOPT, resource_data=resource_data) def handle_adopt(self, resource_data=None): resource_id, data, metadata = self._get_resource_info(resource_data) if not resource_id: exc = Exception(_('Resource ID was not provided.')) failure = exception.ResourceFailure(exc, self) raise failure # set resource id self.resource_id_set(resource_id) # save the resource data if data and isinstance(data, dict): for key, value in data.iteritems(): self.data_set(key, value) # save the resource metadata self.metadata_set(metadata) def _get_resource_info(self, resource_data): if not resource_data: return None, None, None return (resource_data.get('resource_id'), resource_data.get('resource_data'), resource_data.get('metadata')) def update(self, after, before=None, prev_resource=None): ''' update the resource. Subclasses should provide a handle_update() method to customise update, the base-class handle_update will fail by default. ''' action = self.UPDATE (cur_class_def, cur_ver) = self.implementation_signature() prev_ver = cur_ver if prev_resource is not None: (prev_class_def, prev_ver) = prev_resource.implementation_signature() if prev_class_def != cur_class_def: raise UpdateReplace(self.name) if before is None: before = self.parsed_template() if prev_ver == cur_ver and before == after: return if (self.action, self.status) in ((self.CREATE, self.IN_PROGRESS), (self.UPDATE, self.IN_PROGRESS), (self.ADOPT, self.IN_PROGRESS)): exc = Exception(_('Resource update already requested')) raise exception.ResourceFailure(exc, self, action) LOG.info(_('updating %s') % str(self)) try: self.updated_time = datetime.utcnow() self.state_set(action, self.IN_PROGRESS) before_properties = Properties(self.properties_schema, before.get('Properties', {}), function.resolve, self.name, self.context) after_properties = Properties(self.properties_schema, after.get('Properties', {}), function.resolve, self.name, self.context) after_properties.validate() tmpl_diff = self.update_template_diff(function.resolve(after), before) prop_diff = self.update_template_diff_properties(after_properties, before_properties) if callable(getattr(self, 'handle_update', None)): handle_data = self.handle_update(after, tmpl_diff, prop_diff) yield if callable(getattr(self, 'check_update_complete', None)): while not self.check_update_complete(handle_data): yield except UpdateReplace: with excutils.save_and_reraise_exception(): LOG.debug("Resource %s update requires replacement" % self.name) except Exception as ex: LOG.exception(_('update %(resource)s : %(err)s') % {'resource': str(self), 'err': ex}) failure = exception.ResourceFailure(ex, self, action) self.state_set(action, self.FAILED, six.text_type(failure)) raise failure else: self.t = after self.reparse() self.state_set(action, self.COMPLETE) def suspend(self): ''' Suspend the resource. Subclasses should provide a handle_suspend() method to implement suspend ''' action = self.SUSPEND # Don't try to suspend the resource unless it's in a stable state if (self.action == self.DELETE or self.status != self.COMPLETE): exc = exception.Error(_('State %s invalid for suspend') % str(self.state)) raise exception.ResourceFailure(exc, self, action) LOG.info(_('suspending %s') % str(self)) return self._do_action(action) def resume(self): ''' Resume the resource. Subclasses should provide a handle_resume() method to implement resume ''' action = self.RESUME # Can't resume a resource unless it's SUSPEND_COMPLETE if self.state != (self.SUSPEND, self.COMPLETE): exc = exception.Error(_('State %s invalid for resume') % str(self.state)) raise exception.ResourceFailure(exc, self, action) LOG.info(_('resuming %s') % str(self)) return self._do_action(action) def physical_resource_name(self): if self.id is None: return None name = '%s-%s-%s' % (self.stack.name, self.name, short_id.get_id(self.id)) if self.physical_resource_name_limit: name = self.reduce_physical_resource_name( name, self.physical_resource_name_limit) return name @staticmethod def reduce_physical_resource_name(name, limit): ''' Reduce length of physical resource name to a limit. The reduced name will consist of the following: * the first 2 characters of the name * a hyphen * the end of the name, truncated on the left to bring the name length within the limit :param name: The name to reduce the length of :param limit: The max length limit :returns: A name whose length is less than or equal to the limit ''' if len(name) <= limit: return name if limit < 4: raise ValueError(_('limit cannot be less than 4')) postfix_length = limit - 3 return name[0:2] + '-' + name[-postfix_length:] def validate(self): LOG.info(_('Validating %s') % str(self)) function.validate(self.t) self.validate_deletion_policy(self.t) return self.properties.validate() @classmethod def validate_deletion_policy(cls, template): deletion_policy = template.get('DeletionPolicy', DELETE) if deletion_policy not in DELETION_POLICY: msg = _('Invalid DeletionPolicy %s') % deletion_policy raise exception.StackValidationFailed(message=msg) elif deletion_policy == SNAPSHOT: if not callable(getattr(cls, 'handle_snapshot_delete', None)): msg = _('Snapshot DeletionPolicy not supported') raise exception.StackValidationFailed(message=msg) def delete(self): ''' Delete the resource. Subclasses should provide a handle_delete() method to customise deletion. ''' action = self.DELETE if (self.action, self.status) == (self.DELETE, self.COMPLETE): return # No need to delete if the resource has never been created if self.action == self.INIT: return initial_state = self.state LOG.info(_('deleting %s') % str(self)) try: self.state_set(action, self.IN_PROGRESS) if self.abandon_in_progress: deletion_policy = RETAIN else: deletion_policy = self.t.get('DeletionPolicy', DELETE) handle_data = None if deletion_policy == DELETE: if callable(getattr(self, 'handle_delete', None)): handle_data = self.handle_delete() yield elif deletion_policy == SNAPSHOT: if callable(getattr(self, 'handle_snapshot_delete', None)): handle_data = self.handle_snapshot_delete(initial_state) yield if (deletion_policy != RETAIN and callable(getattr(self, 'check_delete_complete', None))): while not self.check_delete_complete(handle_data): yield except Exception as ex: LOG.exception(_('Delete %s') % str(self)) failure = exception.ResourceFailure(ex, self, self.action) self.state_set(action, self.FAILED, six.text_type(failure)) raise failure except: with excutils.save_and_reraise_exception(): try: self.state_set(action, self.FAILED, 'Deletion aborted') except Exception: LOG.exception(_('Error marking resource deletion failed')) else: self.state_set(action, self.COMPLETE) @scheduler.wrappertask def destroy(self): ''' Delete the resource and remove it from the database. ''' yield self.delete() if self.id is None: return try: db_api.resource_get(self.context, self.id).delete() except exception.NotFound: # Don't fail on delete if the db entry has # not been created yet. pass self.id = None def resource_id_set(self, inst): self.resource_id = inst if self.id is not None: try: rs = db_api.resource_get(self.context, self.id) rs.update_and_save({'nova_instance': self.resource_id}) except Exception as ex: LOG.warn(_('db error %s') % ex) def _store(self): '''Create the resource in the database.''' metadata = self.metadata_get() try: rs = {'action': self.action, 'status': self.status, 'status_reason': self.status_reason, 'stack_id': self.stack.id, 'nova_instance': self.resource_id, 'name': self.name, 'rsrc_metadata': metadata, 'stack_name': self.stack.name} new_rs = db_api.resource_create(self.context, rs) self.id = new_rs.id self.created_time = new_rs.created_at self._rsrc_metadata = metadata except Exception as ex: LOG.error(_('DB error %s') % ex) def _add_event(self, action, status, reason): '''Add a state change event to the database.''' ev = event.Event(self.context, self.stack, action, status, reason, self.resource_id, self.properties, self.name, self.type()) ev.store() def _store_or_update(self, action, status, reason): self.action = action self.status = status self.status_reason = reason if self.id is not None: try: rs = db_api.resource_get(self.context, self.id) rs.update_and_save({'action': self.action, 'status': self.status, 'status_reason': reason, 'stack_id': self.stack.id, 'updated_at': self.updated_time, 'nova_instance': self.resource_id}) except Exception as ex: LOG.error(_('DB error %s') % ex) # store resource in DB on transition to CREATE_IN_PROGRESS # all other transitions (other than to DELETE_COMPLETE) # should be handled by the update_and_save above.. elif (action, status) in [(self.CREATE, self.IN_PROGRESS), (self.ADOPT, self.IN_PROGRESS)]: self._store() def _resolve_attribute(self, name): """ Default implementation; should be overridden by resources that expose attributes :param name: The attribute to resolve :returns: the resource attribute named key """ # By default, no attributes resolve pass def state_reset(self): """ Reset state to (INIT, COMPLETE) """ self.action = self.INIT self.status = self.COMPLETE def state_set(self, action, status, reason="state changed"): if action not in self.ACTIONS: raise ValueError(_("Invalid action %s") % action) if status not in self.STATUSES: raise ValueError(_("Invalid status %s") % status) old_state = (self.action, self.status) new_state = (action, status) self._store_or_update(action, status, reason) if new_state != old_state: self._add_event(action, status, reason) @property def state(self): '''Returns state, tuple of action, status.''' return (self.action, self.status) def FnGetRefId(self): ''' For the intrinsic function Ref. :results: the id or name of the resource. ''' if self.resource_id is not None: return unicode(self.resource_id) else: return unicode(self.name) def FnGetAtt(self, key): ''' For the intrinsic function Fn::GetAtt. :param key: the attribute key. :returns: the attribute value. ''' try: return self.attributes[key] except KeyError: raise exception.InvalidTemplateAttribute(resource=self.name, key=key) def FnBase64(self, data): ''' For the instrinsic function Fn::Base64. :param data: the input data. :returns: the Base64 representation of the input data. ''' return base64.b64encode(data) def signal(self, details=None): ''' signal the resource. Subclasses should provide a handle_signal() method to implement the signal, the base-class raise an exception if no handler is implemented. ''' def get_string_details(): if details is None: return 'No signal details provided' if isinstance(details, basestring): return details if isinstance(details, dict): if all(k in details for k in ('previous', 'current', 'reason')): # this is from Ceilometer. auto = '%(previous)s to %(current)s (%(reason)s)' % details return 'alarm state changed from %s' % auto elif 'state' in details: # this is from watchrule return 'alarm state changed to %(state)s' % details elif 'deploy_status_code' in details: # this is for SoftwareDeployment if details['deploy_status_code'] == 0: return 'deployment succeeded' else: return ('deployment failed ' '(%(deploy_status_code)s)' % details) return 'Unknown' try: if not callable(getattr(self, 'handle_signal', None)): msg = (_('Resource %s is not able to receive a signal') % str(self)) raise Exception(msg) self._add_event('signal', self.status, get_string_details()) self.handle_signal(details) except Exception as ex: LOG.exception(_('signal %(name)s : %(msg)s') % {'name': str(self), 'msg': ex}) failure = exception.ResourceFailure(ex, self) raise failure def handle_update(self, json_snippet=None, tmpl_diff=None, prop_diff=None): if prop_diff: raise UpdateReplace(self.name) def metadata_update(self, new_metadata=None): ''' No-op for resources which don't explicitly override this method ''' if new_metadata: LOG.warning(_("Resource %s does not implement metadata update") % self.name) @classmethod def resource_to_template(cls, resource_type): ''' :param resource_type: The resource type to be displayed in the template :returns: A template where the resource's properties_schema is mapped as parameters, and the resource's attributes_schema is mapped as outputs ''' (parameters, properties) = (Properties. schema_to_parameters_and_properties( cls.properties_schema)) resource_name = cls.__name__ return { 'HeatTemplateFormatVersion': '2012-12-12', 'Parameters': parameters, 'Resources': { resource_name: { 'Type': resource_type, 'Properties': properties } }, 'Outputs': Attributes.as_outputs(resource_name, cls) } def data(self): ''' Resource data for this resource Use methods data_set and data_delete to modify the resource data for this resource. :returns: a dict representing the resource data for this resource. ''' if self._data is None and self.id: try: self._data = db_api.resource_data_get_all(self) except exception.NotFound: pass return self._data or {} def data_set(self, key, value, redact=False): '''Save resource's key/value pair to database.''' db_api.resource_data_set(self, key, value, redact) # force fetch all resource data from the database again self._data = None def data_delete(self, key): ''' Remove a resource_data element associated to a resource. :returns: True if the key existed to delete ''' try: db_api.resource_data_delete(self, key) except exception.NotFound: return False else: # force fetch all resource data from the database again self._data = None return True
class Resource(object): ACTIONS = (INIT, CREATE, DELETE, UPDATE, ROLLBACK, SUSPEND, RESUME ) = ('INIT', 'CREATE', 'DELETE', 'UPDATE', 'ROLLBACK', 'SUSPEND', 'RESUME') STATUSES = (IN_PROGRESS, FAILED, COMPLETE ) = ('IN_PROGRESS', 'FAILED', 'COMPLETE') # If True, this resource must be created before it can be referenced. strict_dependency = True created_time = timestamp.Timestamp(db_api.resource_get, 'created_at') updated_time = timestamp.Timestamp(db_api.resource_get, 'updated_at') metadata = Metadata() # Resource implementation set this to the subset of template keys # which are supported for handle_update, used by update_template_diff update_allowed_keys = () # Resource implementation set this to the subset of resource properties # supported for handle_update, used by update_template_diff_properties update_allowed_properties = () # Resource implementations set this to the name: description dictionary # that describes the appropriate resource attributes attributes_schema = {} def __new__(cls, name, json, stack): '''Create a new Resource of the appropriate class for its type.''' if cls != Resource: # Call is already for a subclass, so pass it through return super(Resource, cls).__new__(cls) # Select the correct subclass to instantiate ResourceClass = get_class(json['Type'], resource_name=name, environment=stack.env) return ResourceClass(name, json, stack) def __init__(self, name, json_snippet, stack): if '/' in name: raise ValueError(_('Resource name may not contain "/"')) self.stack = stack self.context = stack.context self.name = name self.json_snippet = json_snippet self.t = stack.resolve_static_data(json_snippet) self.properties = Properties(self.properties_schema, self.t.get('Properties', {}), self.stack.resolve_runtime_data, self.name) self.attributes = Attributes(self.name, self.attributes_schema, self._resolve_attribute) resource = db_api.resource_get_by_name_and_stack(self.context, name, stack.id) if resource: self.resource_id = resource.nova_instance self.action = resource.action self.status = resource.status self.status_reason = resource.status_reason self.id = resource.id self.data = resource.data else: self.resource_id = None # if the stack is being deleted, assume we've already been deleted if stack.action == stack.DELETE: self.action = self.DELETE else: self.action = self.INIT self.status = self.COMPLETE self.status_reason = '' self.id = None self.data = [] def __eq__(self, other): '''Allow == comparison of two resources.''' # For the purposes of comparison, we declare two resource objects # equal if their names and parsed_templates are the same if isinstance(other, Resource): return (self.name == other.name) and ( self.parsed_template() == other.parsed_template()) return NotImplemented def __ne__(self, other): '''Allow != comparison of two resources.''' result = self.__eq__(other) if result is NotImplemented: return result return not result def type(self): return self.t['Type'] def identifier(self): '''Return an identifier for this resource.''' return identifier.ResourceIdentifier(resource_name=self.name, **self.stack.identifier()) def parsed_template(self, section=None, default={}): ''' Return the parsed template data for the resource. May be limited to only one section of the data, in which case a default value may also be supplied. ''' if section is None: template = self.t else: template = self.t.get(section, default) return self.stack.resolve_runtime_data(template) def update_template_diff(self, after, before): ''' Returns the difference between the before and after json snippets. If something has been removed in after which exists in before we set it to None. If any keys have changed which are not in update_allowed_keys, raises UpdateReplace if the differing keys are not in update_allowed_keys ''' update_allowed_set = set(self.update_allowed_keys) # Create a set containing the keys in both current and update template template_keys = set(before.keys()) template_keys.update(set(after.keys())) # Create a set of keys which differ (or are missing/added) changed_keys_set = set([k for k in template_keys if before.get(k) != after.get(k)]) if not changed_keys_set.issubset(update_allowed_set): badkeys = changed_keys_set - update_allowed_set raise UpdateReplace(self.name) return dict((k, after.get(k)) for k in changed_keys_set) def update_template_diff_properties(self, after, before): ''' Returns the changed Properties between the before and after json snippets. If a property has been removed in after which exists in before we set it to None. If any properties have changed which are not in update_allowed_properties, raises UpdateReplace if the modified properties are not in the update_allowed_properties ''' update_allowed_set = set(self.update_allowed_properties) # Create a set containing the keys in both current and update template current_properties = before.get('Properties', {}) template_properties = set(current_properties.keys()) updated_properties = after.get('Properties', {}) template_properties.update(set(updated_properties.keys())) # Create a set of keys which differ (or are missing/added) changed_properties_set = set(k for k in template_properties if current_properties.get(k) != updated_properties.get(k)) if not changed_properties_set.issubset(update_allowed_set): raise UpdateReplace(self.name) return dict((k, updated_properties.get(k)) for k in changed_properties_set) def __str__(self): return '%s "%s"' % (self.__class__.__name__, self.name) def _add_dependencies(self, deps, head, fragment): if isinstance(fragment, dict): for key, value in fragment.items(): if key in ('DependsOn', 'Ref', 'Fn::GetAtt'): if key == 'Fn::GetAtt': value, head = value try: target = self.stack.resources[value] except KeyError: raise exception.InvalidTemplateReference( resource=value, key=head) if key == 'DependsOn' or target.strict_dependency: deps += (self, target) else: self._add_dependencies(deps, key, value) elif isinstance(fragment, list): for item in fragment: self._add_dependencies(deps, head, item) def add_dependencies(self, deps): self._add_dependencies(deps, None, self.t) deps += (self, None) def required_by(self): ''' Returns a list of names of resources which directly require this resource as a dependency. ''' return list( [r.name for r in self.stack.dependencies.required_by(self)]) def keystone(self): return self.stack.clients.keystone() def nova(self, service_type='compute'): return self.stack.clients.nova(service_type) def swift(self): return self.stack.clients.swift() def neutron(self): return self.stack.clients.neutron() def cinder(self): return self.stack.clients.cinder() def ceilometer(self): return self.stack.clients.ceilometer() def _do_action(self, action, pre_func=None): ''' Perform a transition to a new state via a specified action action should be e.g self.CREATE, self.UPDATE etc, we set status based on this, the transistion is handled by calling the corresponding handle_* and check_*_complete functions Note pre_func is an optional function reference which will be called before the handle_<action> function If the resource does not declare a check_$action_complete function, we declare COMPLETE status as soon as the handle_$action call has finished, and if no handle_$action function is declared, then we do nothing, useful e.g if the resource requires no action for a given state transition ''' assert action in self.ACTIONS, 'Invalid action %s' % action try: self.state_set(action, self.IN_PROGRESS) action_l = action.lower() handle = getattr(self, 'handle_%s' % action_l, None) check = getattr(self, 'check_%s_complete' % action_l, None) if callable(pre_func): pre_func() handle_data = None if callable(handle): handle_data = handle() yield if callable(check): while not check(handle_data): yield except Exception as ex: logger.exception('%s : %s' % (action, str(self))) failure = exception.ResourceFailure(ex, self, action) self.state_set(action, self.FAILED, str(failure)) raise failure except: with excutils.save_and_reraise_exception(): try: self.state_set(action, self.FAILED, '%s aborted' % action) except Exception: logger.exception('Error marking resource as failed') else: self.state_set(action, self.COMPLETE) def create(self): ''' Create the resource. Subclasses should provide a handle_create() method to customise creation. ''' action = self.CREATE if (self.action, self.status) != (self.INIT, self.COMPLETE): exc = exception.Error('State %s invalid for create' % str(self.state)) raise exception.ResourceFailure(exc, self, action) logger.info('creating %s' % str(self)) # Re-resolve the template, since if the resource Ref's # the AWS::StackId pseudo parameter, it will change after # the parser.Stack is stored (which is after the resources # are __init__'d, but before they are create()'d) self.t = self.stack.resolve_static_data(self.json_snippet) self.properties = Properties(self.properties_schema, self.t.get('Properties', {}), self.stack.resolve_runtime_data, self.name) return self._do_action(action, self.properties.validate) def update(self, after, before=None): ''' update the resource. Subclasses should provide a handle_update() method to customise update, the base-class handle_update will fail by default. ''' action = self.UPDATE if before is None: before = self.parsed_template() if (self.action, self.status) in ((self.CREATE, self.IN_PROGRESS), (self.UPDATE, self.IN_PROGRESS)): exc = Exception('Resource update already requested') raise exception.ResourceFailure(exc, self, action) logger.info('updating %s' % str(self)) try: self.state_set(action, self.IN_PROGRESS) properties = Properties(self.properties_schema, after.get('Properties', {}), self.stack.resolve_runtime_data, self.name) properties.validate() tmpl_diff = self.update_template_diff(after, before) prop_diff = self.update_template_diff_properties(after, before) if callable(getattr(self, 'handle_update', None)): result = self.handle_update(after, tmpl_diff, prop_diff) except UpdateReplace: logger.debug("Resource %s update requires replacement" % self.name) raise except Exception as ex: logger.exception('update %s : %s' % (str(self), str(ex))) failure = exception.ResourceFailure(ex, self, action) self.state_set(action, self.FAILED, str(failure)) raise failure else: self.t = self.stack.resolve_static_data(after) self.state_set(action, self.COMPLETE) def suspend(self): ''' Suspend the resource. Subclasses should provide a handle_suspend() method to implement suspend ''' action = self.SUSPEND # Don't try to suspend the resource unless it's in a stable state if (self.action == self.DELETE or self.status != self.COMPLETE): exc = exception.Error('State %s invalid for suspend' % str(self.state)) raise exception.ResourceFailure(exc, self, action) logger.info('suspending %s' % str(self)) return self._do_action(action) def resume(self): ''' Resume the resource. Subclasses should provide a handle_resume() method to implement resume ''' action = self.RESUME # Can't resume a resource unless it's SUSPEND_COMPLETE if self.state != (self.SUSPEND, self.COMPLETE): exc = exception.Error('State %s invalid for resume' % str(self.state)) raise exception.ResourceFailure(exc, self, action) logger.info('resuming %s' % str(self)) return self._do_action(action) def physical_resource_name(self): if self.id is None: return None return '%s-%s-%s' % (self.stack.name, self.name, short_id.get_id(self.id)) def validate(self): logger.info('Validating %s' % str(self)) self.validate_deletion_policy(self.t) return self.properties.validate() @classmethod def validate_deletion_policy(cls, template): deletion_policy = template.get('DeletionPolicy', 'Delete') if deletion_policy not in ('Delete', 'Retain', 'Snapshot'): msg = 'Invalid DeletionPolicy %s' % deletion_policy raise exception.StackValidationFailed(message=msg) elif deletion_policy == 'Snapshot': if not callable(getattr(cls, 'handle_snapshot_delete', None)): msg = 'Snapshot DeletionPolicy not supported' raise exception.StackValidationFailed(message=msg) def delete(self): ''' Delete the resource. Subclasses should provide a handle_delete() method to customise deletion. ''' action = self.DELETE if (self.action, self.status) == (self.DELETE, self.COMPLETE): return # No need to delete if the resource has never been created if self.action == self.INIT: return initial_state = self.state logger.info('deleting %s' % str(self)) try: self.state_set(action, self.IN_PROGRESS) deletion_policy = self.t.get('DeletionPolicy', 'Delete') if deletion_policy == 'Delete': if callable(getattr(self, 'handle_delete', None)): self.handle_delete() elif deletion_policy == 'Snapshot': if callable(getattr(self, 'handle_snapshot_delete', None)): self.handle_snapshot_delete(initial_state) except Exception as ex: logger.exception('Delete %s', str(self)) failure = exception.ResourceFailure(ex, self, self.action) self.state_set(action, self.FAILED, str(failure)) raise failure except: with excutils.save_and_reraise_exception(): try: self.state_set(action, self.FAILED, 'Deletion aborted') except Exception: logger.exception('Error marking resource deletion failed') else: self.state_set(action, self.COMPLETE) def destroy(self): ''' Delete the resource and remove it from the database. ''' self.delete() if self.id is None: return try: db_api.resource_get(self.context, self.id).delete() except exception.NotFound: # Don't fail on delete if the db entry has # not been created yet. pass self.id = None def resource_id_set(self, inst): self.resource_id = inst if self.id is not None: try: rs = db_api.resource_get(self.context, self.id) rs.update_and_save({'nova_instance': self.resource_id}) except Exception as ex: logger.warn('db error %s' % str(ex)) def _store(self): '''Create the resource in the database.''' try: rs = {'action': self.action, 'status': self.status, 'status_reason': self.status_reason, 'stack_id': self.stack.id, 'nova_instance': self.resource_id, 'name': self.name, 'rsrc_metadata': self.metadata, 'stack_name': self.stack.name} new_rs = db_api.resource_create(self.context, rs) self.id = new_rs.id self.stack.updated_time = datetime.utcnow() except Exception as ex: logger.error('DB error %s' % str(ex)) def _add_event(self, action, status, reason): '''Add a state change event to the database.''' ev = event.Event(self.context, self.stack, self, action, status, reason, self.resource_id, self.properties) try: ev.store() except Exception as ex: logger.error('DB error %s' % str(ex)) def _store_or_update(self, action, status, reason): self.action = action self.status = status self.status_reason = reason if self.id is not None: try: rs = db_api.resource_get(self.context, self.id) rs.update_and_save({'action': self.action, 'status': self.status, 'status_reason': reason, 'nova_instance': self.resource_id}) self.stack.updated_time = datetime.utcnow() except Exception as ex: logger.error('DB error %s' % str(ex)) # store resource in DB on transition to CREATE_IN_PROGRESS # all other transistions (other than to DELETE_COMPLETE) # should be handled by the update_and_save above.. elif (action, status) == (self.CREATE, self.IN_PROGRESS): self._store() def _resolve_attribute(self, name): """ Default implementation; should be overridden by resources that expose attributes :param name: The attribute to resolve :returns: the resource attribute named key """ # By default, no attributes resolve pass def state_reset(self): """ Reset state to (INIT, COMPLETE) """ self.action = self.INIT self.status = self.COMPLETE def state_set(self, action, status, reason="state changed"): if action not in self.ACTIONS: raise ValueError("Invalid action %s" % action) if status not in self.STATUSES: raise ValueError("Invalid status %s" % status) old_state = (self.action, self.status) new_state = (action, status) self._store_or_update(action, status, reason) if new_state != old_state: self._add_event(action, status, reason) @property def state(self): '''Returns state, tuple of action, status.''' return (self.action, self.status) def FnGetRefId(self): ''' http://docs.amazonwebservices.com/AWSCloudFormation/latest/UserGuide/\ intrinsic-function-reference-ref.html ''' if self.resource_id is not None: return unicode(self.resource_id) else: return unicode(self.name) def FnGetAtt(self, key): ''' http://docs.amazonwebservices.com/AWSCloudFormation/latest/UserGuide/\ intrinsic-function-reference-getatt.html ''' try: return self.attributes[key] except KeyError: raise exception.InvalidTemplateAttribute(resource=self.name, key=key) def FnBase64(self, data): ''' http://docs.amazonwebservices.com/AWSCloudFormation/latest/UserGuide/\ intrinsic-function-reference-base64.html ''' return base64.b64encode(data) def signal(self, details=None): ''' signal the resource. Subclasses should provide a handle_signal() method to implement the signal, the base-class raise an exception if no handler is implemented. ''' try: if self.action in (self.SUSPEND, self.DELETE): msg = 'Cannot signal resource during %s' % self.action raise Exception(msg) if not callable(getattr(self, 'handle_signal', None)): msg = 'Resource %s is not able to receive a signal' % str(self) raise Exception(msg) self._add_event('signal', self.status, details) self.handle_signal(details) except Exception as ex: logger.exception('signal %s : %s' % (str(self), str(ex))) failure = exception.ResourceFailure(ex, self) raise failure def handle_update(self, json_snippet=None, tmpl_diff=None, prop_diff=None): raise UpdateReplace(self.name) def metadata_update(self, new_metadata=None): ''' No-op for resources which don't explicitly override this method ''' if new_metadata: logger.warning("Resource %s does not implement metadata update" % self.name) @classmethod def resource_to_template(cls, resource_type): ''' :param resource_type: The resource type to be displayed in the template :param explode_nested: True if a resource's nested properties schema should be resolved. :returns: A template where the resource's properties_schema is mapped as parameters, and the resource's attributes_schema is mapped as outputs ''' (parameters, properties) = (Properties. schema_to_parameters_and_properties( cls.properties_schema)) resource_name = cls.__name__ return { 'Parameters': parameters, 'Resources': { resource_name: { 'Type': resource_type, 'Properties': properties } }, 'Outputs': Attributes.as_outputs(resource_name, cls) }
class InstanceGroup(stack_resource.StackResource): tags_schema = { 'Key': { 'Type': 'String', 'Required': True }, 'Value': { 'Type': 'String', 'Required': True } } properties_schema = { 'AvailabilityZones': { 'Required': True, 'Type': 'List' }, 'LaunchConfigurationName': { 'Required': True, 'Type': 'String' }, 'Size': { 'Required': True, 'Type': 'Number' }, 'LoadBalancerNames': { 'Type': 'List' }, 'Tags': { 'Type': 'List', 'Schema': { 'Type': 'Map', 'Schema': tags_schema } } } update_allowed_keys = ( 'Properties', 'UpdatePolicy', ) update_allowed_properties = ( 'Size', 'LaunchConfigurationName', ) attributes_schema = { "InstanceList": ("A comma-delimited list of server ip addresses. " "(Heat extension)") } rolling_update_schema = { 'MinInstancesInService': properties.Schema(properties.NUMBER, default=0), 'MaxBatchSize': properties.Schema(properties.NUMBER, default=1), 'PauseTime': properties.Schema(properties.STRING, default='PT0S') } update_policy_schema = { 'RollingUpdate': properties.Schema(properties.MAP, schema=rolling_update_schema) } def __init__(self, name, json_snippet, stack): """ UpdatePolicy is currently only specific to InstanceGroup and AutoScalingGroup. Therefore, init is overridden to parse for the UpdatePolicy. """ super(InstanceGroup, self).__init__(name, json_snippet, stack) self.update_policy = Properties(self.update_policy_schema, self.t.get('UpdatePolicy', {}), parent_name=self.name) def validate(self): """ Add validation for update_policy """ super(InstanceGroup, self).validate() if self.update_policy: self.update_policy.validate() def get_instance_names(self): """Get a list of resource names of the instances in this InstanceGroup. Failed resources will be ignored. """ return sorted(x.name for x in self.get_instances()) def get_instances(self): """Get a set of all the instance resources managed by this group.""" return [ resource for resource in self.nested() if resource.state[1] != resource.FAILED ] def handle_create(self): """Create a nested stack and add the initial resources to it.""" num_instances = int(self.properties['Size']) initial_template = self._create_template(num_instances) return self.create_with_template(initial_template, {}) def check_create_complete(self, task): """ When stack creation is done, update the load balancer. If any instances failed to be created, delete them. """ done = super(InstanceGroup, self).check_create_complete(task) if done: self._lb_reload() return done def handle_update(self, json_snippet, tmpl_diff, prop_diff): """ If Properties has changed, update self.properties, so we get the new values during any subsequent adjustment. """ if tmpl_diff: # parse update policy if 'UpdatePolicy' in tmpl_diff: self.update_policy = Properties(self.update_policy_schema, json_snippet.get( 'UpdatePolicy', {}), parent_name=self.name) if prop_diff: self.properties = Properties(self.properties_schema, json_snippet.get('Properties', {}), self.stack.resolve_runtime_data, self.name) # Get the current capacity, we may need to adjust if # Size has changed if 'Size' in prop_diff: inst_list = self.get_instances() if len(inst_list) != int(self.properties['Size']): self.resize(int(self.properties['Size'])) def _tags(self): """ Make sure that we add a tag that Ceilometer can pick up. These need to be prepended with 'metering.'. """ tags = self.properties.get('Tags') or [] for t in tags: if t['Key'].startswith('metering.'): # the user has added one, don't add another. return tags return tags + [{ 'Key': 'metering.groupname', 'Value': self.FnGetRefId() }] def handle_delete(self): return self.delete_nested() def _create_template(self, num_instances): """ Create a template with a number of instance definitions based on the launch configuration. """ conf_name = self.properties['LaunchConfigurationName'] conf = self.stack.resource_by_refid(conf_name) instance_definition = copy.deepcopy(conf.t) instance_definition['Type'] = 'AWS::EC2::Instance' instance_definition['Properties']['Tags'] = self._tags() if self.properties.get('VPCZoneIdentifier'): instance_definition['Properties']['SubnetId'] = \ self.properties['VPCZoneIdentifier'][0] # resolve references within the context of this stack. fully_parsed = self.stack.resolve_runtime_data(instance_definition) resources = {} for i in range(num_instances): resources["%s-%d" % (self.name, i)] = fully_parsed return {"Resources": resources} def resize(self, new_capacity): """ Resize the instance group to the new capacity. When shrinking, the newest instances will be removed. """ new_template = self._create_template(new_capacity) try: self.update_with_template(new_template, {}) finally: # Reload the LB in any case, so it's only pointing at healthy # nodes. self._lb_reload() def _lb_reload(self): ''' Notify the LoadBalancer to reload its config to include the changes in instances we have just made. This must be done after activation (instance in ACTIVE state), otherwise the instances' IP addresses may not be available. ''' if self.properties['LoadBalancerNames']: id_list = [inst.FnGetRefId() for inst in self.get_instances()] for lb in self.properties['LoadBalancerNames']: lb_resource = self.stack[lb] if 'Instances' in lb_resource.properties_schema: lb_resource.json_snippet['Properties']['Instances'] = ( id_list) elif 'members' in lb_resource.properties_schema: lb_resource.json_snippet['Properties']['members'] = ( id_list) else: raise exception.Error( "Unsupported resource '%s' in LoadBalancerNames" % (lb, )) resolved_snippet = self.stack.resolve_static_data( lb_resource.json_snippet) scheduler.TaskRunner(lb_resource.update, resolved_snippet)() def FnGetRefId(self): return unicode(self.name) def _resolve_attribute(self, name): ''' heat extension: "InstanceList" returns comma delimited list of server ip addresses. ''' if name == 'InstanceList': ips = [ inst.FnGetAtt('PublicIp') for inst in self._nested.resources.values() ] if ips: return unicode(','.join(ips))
class Resource(object): # Status strings CREATE_IN_PROGRESS = 'IN_PROGRESS' CREATE_FAILED = 'CREATE_FAILED' CREATE_COMPLETE = 'CREATE_COMPLETE' DELETE_IN_PROGRESS = 'DELETE_IN_PROGRESS' DELETE_FAILED = 'DELETE_FAILED' DELETE_COMPLETE = 'DELETE_COMPLETE' UPDATE_IN_PROGRESS = 'UPDATE_IN_PROGRESS' UPDATE_FAILED = 'UPDATE_FAILED' UPDATE_COMPLETE = 'UPDATE_COMPLETE' # Status values, returned from subclasses to indicate update method UPDATE_REPLACE = 'UPDATE_REPLACE' UPDATE_INTERRUPTION = 'UPDATE_INTERRUPTION' UPDATE_NO_INTERRUPTION = 'UPDATE_NO_INTERRUPTION' UPDATE_NOT_IMPLEMENTED = 'UPDATE_NOT_IMPLEMENTED' # If True, this resource must be created before it can be referenced. strict_dependency = True created_time = timestamp.Timestamp(db_api.resource_get, 'created_at') updated_time = timestamp.Timestamp(db_api.resource_get, 'updated_at') metadata = Metadata() def __new__(cls, name, json, stack): '''Create a new Resource of the appropriate class for its type.''' if cls != Resource: # Call is already for a subclass, so pass it through return super(Resource, cls).__new__(cls) # Select the correct subclass to instantiate ResourceClass = get_class(json['Type']) or GenericResource return ResourceClass(name, json, stack) def __init__(self, name, json_snippet, stack): if '/' in name: raise ValueError(_('Resource name may not contain "/"')) self.references = [] self.stack = stack self.context = stack.context self.name = name self.t = stack.resolve_static_data(json_snippet) self.properties = Properties(self.properties_schema, self.t.get('Properties', {}), self.stack.resolve_runtime_data, self.name) resource = db_api.resource_get_by_name_and_stack(self.context, name, stack.id) if resource: self.resource_id = resource.nova_instance self.state = resource.state self.state_description = resource.state_description self.id = resource.id else: self.resource_id = None self.state = None self.state_description = '' self.id = None self._nova = {} self._keystone = None self._swift = None self._quantum = None def __eq__(self, other): '''Allow == comparison of two resources''' # For the purposes of comparison, we declare two resource objects # equal if their names and parsed_templates are the same if isinstance(other, Resource): return (self.name == other.name) and ( self.parsed_template() == other.parsed_template()) return NotImplemented def __ne__(self, other): '''Allow != comparison of two resources''' result = self.__eq__(other) if result is NotImplemented: return result return not result def type(self): return self.t['Type'] def identifier(self): '''Return an identifier for this resource''' return identifier.ResourceIdentifier(resource_name=self.name, **self.stack.identifier()) def parsed_template(self, section=None, default={}): ''' Return the parsed template data for the resource. May be limited to only one section of the data, in which case a default value may also be supplied. ''' if section is None: template = self.t else: template = self.t.get(section, default) return self.stack.resolve_runtime_data(template) def __str__(self): return '%s "%s"' % (self.__class__.__name__, self.name) def _add_dependencies(self, deps, fragment): if isinstance(fragment, dict): for key, value in fragment.items(): if key in ('DependsOn', 'Ref'): target = self.stack.resources[value] if key == 'DependsOn' or target.strict_dependency: deps += (self, target) elif key != 'Fn::GetAtt': self._add_dependencies(deps, value) elif isinstance(fragment, list): for item in fragment: self._add_dependencies(deps, item) def add_dependencies(self, deps): self._add_dependencies(deps, self.t) deps += (self, None) def keystone(self): return self.stack.clients.keystone() def nova(self, service_type='compute'): return self.stack.clients.nova(service_type) def swift(self): return self.stack.clients.swift() def quantum(self): return self.stack.clients.quantum() def create(self): ''' Create the resource. Subclasses should provide a handle_create() method to customise creation. ''' if self.state in (self.CREATE_IN_PROGRESS, self.CREATE_COMPLETE): return 'Resource creation already requested' logger.info('creating %s' % str(self)) try: err = self.properties.validate() if err: return err self.state_set(self.CREATE_IN_PROGRESS) if callable(getattr(self, 'handle_create', None)): self.handle_create() except Exception as ex: logger.exception('create %s', str(self)) self.state_set(self.CREATE_FAILED, str(ex)) return str(ex) else: self.state_set(self.CREATE_COMPLETE) def update(self, json_snippet=None): ''' update the resource. Subclasses should provide a handle_update() method to customise update, the base-class handle_update will fail by default. ''' if self.state in (self.CREATE_IN_PROGRESS, self.UPDATE_IN_PROGRESS): return 'Resource update already requested' if not json_snippet: return 'Must specify json snippet for resource update!' logger.info('updating %s' % str(self)) result = self.UPDATE_NOT_IMPLEMENTED try: self.state_set(self.UPDATE_IN_PROGRESS) self.t = self.stack.resolve_static_data(json_snippet) err = self.properties.validate() if err: return err if callable(getattr(self, 'handle_update', None)): result = self.handle_update() except Exception as ex: logger.exception('update %s : %s' % (str(self), str(ex))) self.state_set(self.UPDATE_FAILED, str(ex)) return str(ex) else: # If resource was updated (with or without interruption), # then we set the resource to UPDATE_COMPLETE if not result == self.UPDATE_REPLACE: self.state_set(self.UPDATE_COMPLETE) return result def physical_resource_name(self): return '%s.%s' % (self.stack.name, self.name) def physical_resource_name_find(self, resource_name): if resource_name in self.stack: return '%s.%s' % (self.stack.name, resource_name) else: raise IndexError('no such resource') def validate(self): logger.info('Validating %s' % str(self)) return self.properties.validate() def delete(self): ''' Delete the resource. Subclasses should provide a handle_delete() method to customise deletion. ''' if self.state == self.DELETE_COMPLETE: return if self.state == self.DELETE_IN_PROGRESS: return 'Resource deletion already in progress' logger.info('deleting %s (inst:%s db_id:%s)' % (str(self), self.resource_id, str(self.id))) self.state_set(self.DELETE_IN_PROGRESS) try: if callable(getattr(self, 'handle_delete', None)): self.handle_delete() except Exception as ex: logger.exception('Delete %s', str(self)) self.state_set(self.DELETE_FAILED, str(ex)) return str(ex) self.state_set(self.DELETE_COMPLETE) def destroy(self): ''' Delete the resource and remove it from the database. ''' result = self.delete() if result: return result if self.id is None: return try: db_api.resource_get(self.context, self.id).delete() except exception.NotFound: # Don't fail on delete if the db entry has # not been created yet. pass except Exception as ex: logger.exception('Delete %s from DB' % str(self)) return str(ex) self.id = None def resource_id_set(self, inst): self.resource_id = inst if self.id is not None: try: rs = db_api.resource_get(self.context, self.id) rs.update_and_save({'nova_instance': self.resource_id}) except Exception as ex: logger.warn('db error %s' % str(ex)) def _store(self): '''Create the resource in the database''' try: rs = {'state': self.state, 'stack_id': self.stack.id, 'nova_instance': self.resource_id, 'name': self.name, 'rsrc_metadata': self.metadata, 'stack_name': self.stack.name} new_rs = db_api.resource_create(self.context, rs) self.id = new_rs.id self.stack.updated_time = datetime.utcnow() except Exception as ex: logger.error('DB error %s' % str(ex)) def _add_event(self, new_state, reason): '''Add a state change event to the database''' ev = event.Event(self.context, self.stack, self, new_state, reason, self.resource_id, self.properties) try: ev.store() except Exception as ex: logger.error('DB error %s' % str(ex)) def _store_or_update(self, new_state, reason): self.state = new_state self.state_description = reason if self.id is not None: try: rs = db_api.resource_get(self.context, self.id) rs.update_and_save({'state': self.state, 'state_description': reason, 'nova_instance': self.resource_id}) self.stack.updated_time = datetime.utcnow() except Exception as ex: logger.error('DB error %s' % str(ex)) # store resource in DB on transition to CREATE_IN_PROGRESS # all other transistions (other than to DELETE_COMPLETE) # should be handled by the update_and_save above.. elif new_state == self.CREATE_IN_PROGRESS: self._store() def state_set(self, new_state, reason="state changed"): old_state = self.state self._store_or_update(new_state, reason) if new_state != old_state: self._add_event(new_state, reason) def FnGetRefId(self): ''' http://docs.amazonwebservices.com/AWSCloudFormation/latest/UserGuide/\ intrinsic-function-reference-ref.html ''' if self.resource_id is not None: return unicode(self.resource_id) else: return unicode(self.name) def FnGetAtt(self, key): ''' http://docs.amazonwebservices.com/AWSCloudFormation/latest/UserGuide/\ intrinsic-function-reference-getatt.html ''' return unicode(self.name) def FnBase64(self, data): ''' http://docs.amazonwebservices.com/AWSCloudFormation/latest/UserGuide/\ intrinsic-function-reference-base64.html ''' return base64.b64encode(data) def handle_update(self): raise NotImplementedError("Update not implemented for Resource %s" % type(self))
class Resource(object): ACTIONS = (INIT, CREATE, DELETE, UPDATE, ROLLBACK, SUSPEND, RESUME, ADOPT) = ('INIT', 'CREATE', 'DELETE', 'UPDATE', 'ROLLBACK', 'SUSPEND', 'RESUME', 'ADOPT') STATUSES = (IN_PROGRESS, FAILED, COMPLETE) = ('IN_PROGRESS', 'FAILED', 'COMPLETE') # If True, this resource must be created before it can be referenced. strict_dependency = True created_time = timestamp.Timestamp(db_api.resource_get, 'created_at') updated_time = timestamp.Timestamp(db_api.resource_get, 'updated_at') _metadata = Metadata() # Resource implementation set this to the subset of template keys # which are supported for handle_update, used by update_template_diff update_allowed_keys = () # Resource implementation set this to the subset of resource properties # supported for handle_update, used by update_template_diff_properties update_allowed_properties = () # Resource implementations set this to the name: description dictionary # that describes the appropriate resource attributes attributes_schema = {} # If True, this resource may perform authenticated API requests # throughout its lifecycle requires_deferred_auth = False # Limit to apply to physical_resource_name() size reduction algorithm. # If set to None no limit will be applied. physical_resource_name_limit = 255 support_status = SupportStatus() def __new__(cls, name, json, stack): '''Create a new Resource of the appropriate class for its type.''' if cls != Resource: # Call is already for a subclass, so pass it through return super(Resource, cls).__new__(cls) # Select the correct subclass to instantiate ResourceClass = stack.env.get_class(json.get('Type'), resource_name=name) return ResourceClass(name, json, stack) def __init__(self, name, json_snippet, stack): if '/' in name: raise ValueError(_('Resource name may not contain "/"')) self.stack = stack self.context = stack.context self.name = name self.json_snippet = json_snippet self.t = stack.resolve_static_data(json_snippet) self.properties = Properties(self.properties_schema, self.t.get('Properties', {}), self._resolve_runtime_data, self.name) self.attributes = Attributes(self.name, self.attributes_schema, self._resolve_attribute) if stack.id: resource = db_api.resource_get_by_name_and_stack( self.context, name, stack.id) else: resource = None if resource: self.resource_id = resource.nova_instance self.action = resource.action self.status = resource.status self.status_reason = resource.status_reason self.id = resource.id self.data = resource.data else: self.resource_id = None # if the stack is being deleted, assume we've already been deleted if stack.action == stack.DELETE: self.action = self.DELETE else: self.action = self.INIT self.status = self.COMPLETE self.status_reason = '' self.id = None self.data = [] def __eq__(self, other): '''Allow == comparison of two resources.''' # For the purposes of comparison, we declare two resource objects # equal if their names and parsed_templates are the same if isinstance(other, Resource): return (self.name == other.name) and (self.parsed_template() == other.parsed_template()) return NotImplemented def __ne__(self, other): '''Allow != comparison of two resources.''' result = self.__eq__(other) if result is NotImplemented: return result return not result @property def metadata(self): return self._metadata @metadata.setter def metadata(self, metadata): self._metadata = metadata def type(self): return self.t['Type'] def _resolve_runtime_data(self, snippet): return self.stack.resolve_runtime_data(snippet) def has_interface(self, resource_type): """Check to see if this resource is either mapped to resource_type or is a "resource_type". """ if self.type() == resource_type: return True ri = self.stack.env.get_resource_info(self.type(), self.name) return ri.name == resource_type def implementation_signature(self): ''' Return a tuple defining the implementation. This should be broken down into a definition and an implementation version. ''' return (self.__class__.__name__, self.support_status.version) def identifier(self): '''Return an identifier for this resource.''' return identifier.ResourceIdentifier(resource_name=self.name, **self.stack.identifier()) def parsed_template(self, section=None, default={}): ''' Return the parsed template data for the resource. May be limited to only one section of the data, in which case a default value may also be supplied. ''' if section is None: template = self.t else: template = self.t.get(section, default) return self._resolve_runtime_data(template) def update_template_diff(self, after, before): ''' Returns the difference between the before and after json snippets. If something has been removed in after which exists in before we set it to None. If any keys have changed which are not in update_allowed_keys, raises UpdateReplace if the differing keys are not in update_allowed_keys ''' update_allowed_set = set(self.update_allowed_keys) # Create a set containing the keys in both current and update template template_keys = set(before.keys()) template_keys.update(set(after.keys())) # Create a set of keys which differ (or are missing/added) changed_keys_set = set( [k for k in template_keys if before.get(k) != after.get(k)]) if not changed_keys_set.issubset(update_allowed_set): raise UpdateReplace(self.name) return dict((k, after.get(k)) for k in changed_keys_set) def update_template_diff_properties(self, after, before): ''' Returns the changed Properties between the before and after json snippets. If a property has been removed in after which exists in before we set it to None. If any properties have changed which are not in update_allowed_properties, raises UpdateReplace if the modified properties are not in the update_allowed_properties ''' update_allowed_set = set(self.update_allowed_properties) for (psk, psv) in self.properties.props.iteritems(): if psv.update_allowed(): update_allowed_set.add(psk) # Create a set containing the keys in both current and update template current_properties = before.get('Properties', {}) template_properties = set(current_properties.keys()) updated_properties = after.get('Properties', {}) template_properties.update(set(updated_properties.keys())) # Create a set of keys which differ (or are missing/added) changed_properties_set = set( k for k in template_properties if current_properties.get(k) != updated_properties.get(k)) if not changed_properties_set.issubset(update_allowed_set): raise UpdateReplace(self.name) return dict( (k, updated_properties.get(k)) for k in changed_properties_set) def __str__(self): if self.stack.id: if self.resource_id: return '%s "%s" [%s] %s' % (self.__class__.__name__, self.name, self.resource_id, str(self.stack)) return '%s "%s" %s' % (self.__class__.__name__, self.name, str(self.stack)) return '%s "%s"' % (self.__class__.__name__, self.name) def _add_dependencies(self, deps, path, fragment): if isinstance(fragment, dict): for key, value in fragment.items(): if key in ('DependsOn', 'Ref', 'Fn::GetAtt', 'get_attr', 'get_resource'): if key in ('Fn::GetAtt', 'get_attr'): res_name = value[0] res_list = [res_name] elif key == 'DependsOn' and isinstance(value, list): res_list = value else: res_list = [value] for res in res_list: try: target = self.stack[res] except KeyError: raise exception.InvalidTemplateReference( resource=res, key=path) if key == 'DependsOn' or target.strict_dependency: deps += (self, target) else: self._add_dependencies(deps, '%s.%s' % (path, key), value) elif isinstance(fragment, list): for index, item in enumerate(fragment): self._add_dependencies(deps, '%s[%d]' % (path, index), item) def add_dependencies(self, deps): self._add_dependencies(deps, self.name, self.t) deps += (self, None) def required_by(self): ''' Returns a list of names of resources which directly require this resource as a dependency. ''' return list( [r.name for r in self.stack.dependencies.required_by(self)]) def keystone(self): return self.stack.clients.keystone() def nova(self, service_type='compute'): return self.stack.clients.nova(service_type) def swift(self): return self.stack.clients.swift() def neutron(self): return self.stack.clients.neutron() def cinder(self): return self.stack.clients.cinder() def trove(self): return self.stack.clients.trove() def ceilometer(self): return self.stack.clients.ceilometer() def heat(self): return self.stack.clients.heat() def _do_action(self, action, pre_func=None, resource_data=None): ''' Perform a transition to a new state via a specified action action should be e.g self.CREATE, self.UPDATE etc, we set status based on this, the transistion is handled by calling the corresponding handle_* and check_*_complete functions Note pre_func is an optional function reference which will be called before the handle_<action> function If the resource does not declare a check_$action_complete function, we declare COMPLETE status as soon as the handle_$action call has finished, and if no handle_$action function is declared, then we do nothing, useful e.g if the resource requires no action for a given state transition ''' assert action in self.ACTIONS, 'Invalid action %s' % action try: self.state_set(action, self.IN_PROGRESS) action_l = action.lower() handle = getattr(self, 'handle_%s' % action_l, None) check = getattr(self, 'check_%s_complete' % action_l, None) if callable(pre_func): pre_func() handle_data = None if callable(handle): handle_data = (handle(resource_data) if resource_data else handle()) yield if callable(check): while not check(handle_data): yield except Exception as ex: logger.exception('%s : %s' % (action, str(self))) failure = exception.ResourceFailure(ex, self, action) self.state_set(action, self.FAILED, str(failure)) raise failure except: with excutils.save_and_reraise_exception(): try: self.state_set(action, self.FAILED, '%s aborted' % action) except Exception: logger.exception(_('Error marking resource as failed')) else: self.state_set(action, self.COMPLETE) def create(self): ''' Create the resource. Subclasses should provide a handle_create() method to customise creation. ''' action = self.CREATE if (self.action, self.status) != (self.INIT, self.COMPLETE): exc = exception.Error( _('State %s invalid for create') % str(self.state)) raise exception.ResourceFailure(exc, self, action) logger.info('creating %s' % str(self)) # Re-resolve the template, since if the resource Ref's # the StackId pseudo parameter, it will change after # the parser.Stack is stored (which is after the resources # are __init__'d, but before they are create()'d) self.t = self.stack.resolve_static_data(self.json_snippet) self.properties = Properties(self.properties_schema, self.t.get('Properties', {}), self._resolve_runtime_data, self.name) return self._do_action(action, self.properties.validate) def set_deletion_policy(self, policy): self.t['DeletionPolicy'] = policy def get_abandon_data(self): return { 'name': self.name, 'resource_id': self.resource_id, 'type': self.type(), 'action': self.action, 'status': self.status, 'metadata': self.metadata, 'resource_data': dict((r.key, r.value) for r in db_api.resource_data_get_all(self)) } def adopt(self, resource_data): ''' Adopt the existing resource. Resource subclasses can provide a handle_adopt() method to customise adopt. ''' return self._do_action(self.ADOPT, resource_data=resource_data) def handle_adopt(self, resource_data=None): resource_id, data, metadata = self._get_resource_info(resource_data) if not resource_id: exc = Exception(_('Resource ID was not provided.')) failure = exception.ResourceFailure(exc, self) raise failure # set resource id self.resource_id_set(resource_id) # save the resource data if data and isinstance(data, dict): for key, value in data.iteritems(): db_api.resource_data_set(self, key, value) # save the resource metadata self.metadata = metadata def _get_resource_info(self, resource_data): if not resource_data: return None, None, None return (resource_data.get('resource_id'), resource_data.get('resource_data'), resource_data.get('metadata')) def update(self, after, before=None, prev_resource=None): ''' update the resource. Subclasses should provide a handle_update() method to customise update, the base-class handle_update will fail by default. ''' action = self.UPDATE (cur_class_def, cur_ver) = self.implementation_signature() prev_ver = cur_ver if prev_resource is not None: (prev_class_def, prev_ver) = prev_resource.implementation_signature() if prev_class_def != cur_class_def: raise UpdateReplace(self.name) if before is None: before = self.parsed_template() if prev_ver == cur_ver and before == after: return if (self.action, self.status) in ((self.CREATE, self.IN_PROGRESS), (self.UPDATE, self.IN_PROGRESS), (self.ADOPT, self.IN_PROGRESS)): exc = Exception(_('Resource update already requested')) raise exception.ResourceFailure(exc, self, action) logger.info('updating %s' % str(self)) try: self.state_set(action, self.IN_PROGRESS) properties = Properties(self.properties_schema, after.get('Properties', {}), self._resolve_runtime_data, self.name) properties.validate() tmpl_diff = self.update_template_diff(after, before) prop_diff = self.update_template_diff_properties(after, before) if callable(getattr(self, 'handle_update', None)): handle_data = self.handle_update(after, tmpl_diff, prop_diff) yield if callable(getattr(self, 'check_update_complete', None)): while not self.check_update_complete(handle_data): yield except UpdateReplace: with excutils.save_and_reraise_exception(): logger.debug( _("Resource %s update requires replacement") % self.name) except Exception as ex: logger.exception('update %s : %s' % (str(self), str(ex))) failure = exception.ResourceFailure(ex, self, action) self.state_set(action, self.FAILED, str(failure)) raise failure else: self.t = self.stack.resolve_static_data(after) self.state_set(action, self.COMPLETE) def suspend(self): ''' Suspend the resource. Subclasses should provide a handle_suspend() method to implement suspend ''' action = self.SUSPEND # Don't try to suspend the resource unless it's in a stable state if (self.action == self.DELETE or self.status != self.COMPLETE): exc = exception.Error( _('State %s invalid for suspend') % str(self.state)) raise exception.ResourceFailure(exc, self, action) logger.info(_('suspending %s') % str(self)) return self._do_action(action) def resume(self): ''' Resume the resource. Subclasses should provide a handle_resume() method to implement resume ''' action = self.RESUME # Can't resume a resource unless it's SUSPEND_COMPLETE if self.state != (self.SUSPEND, self.COMPLETE): exc = exception.Error( _('State %s invalid for resume') % str(self.state)) raise exception.ResourceFailure(exc, self, action) logger.info(_('resuming %s') % str(self)) return self._do_action(action) def physical_resource_name(self): if self.id is None: return None name = '%s-%s-%s' % (self.stack.name, self.name, short_id.get_id(self.id)) if self.physical_resource_name_limit: name = self.reduce_physical_resource_name( name, self.physical_resource_name_limit) return name @staticmethod def reduce_physical_resource_name(name, limit): ''' Reduce length of physical resource name to a limit. The reduced name will consist of the following: * the first 2 characters of the name * a hyphen * the end of the name, truncated on the left to bring the name length within the limit :param name: The name to reduce the length of :param limit: The max length limit :returns: A name whose length is less than or equal to the limit ''' if len(name) <= limit: return name if limit < 4: raise ValueError(_('limit cannot be less than 4')) postfix_length = limit - 3 return name[0:2] + '-' + name[-postfix_length:] def validate(self): logger.info(_('Validating %s') % str(self)) self.validate_deletion_policy(self.t) return self.properties.validate() @classmethod def validate_deletion_policy(cls, template): deletion_policy = template.get('DeletionPolicy', DELETE) if deletion_policy not in DELETION_POLICY: msg = _('Invalid DeletionPolicy %s') % deletion_policy raise exception.StackValidationFailed(message=msg) elif deletion_policy == SNAPSHOT: if not callable(getattr(cls, 'handle_snapshot_delete', None)): msg = _('Snapshot DeletionPolicy not supported') raise exception.StackValidationFailed(message=msg) def delete(self): ''' Delete the resource. Subclasses should provide a handle_delete() method to customise deletion. ''' action = self.DELETE if (self.action, self.status) == (self.DELETE, self.COMPLETE): return # No need to delete if the resource has never been created if self.action == self.INIT: return initial_state = self.state logger.info(_('deleting %s') % str(self)) try: self.state_set(action, self.IN_PROGRESS) deletion_policy = self.t.get('DeletionPolicy', DELETE) handle_data = None if deletion_policy == DELETE: if callable(getattr(self, 'handle_delete', None)): handle_data = self.handle_delete() yield elif deletion_policy == SNAPSHOT: if callable(getattr(self, 'handle_snapshot_delete', None)): handle_data = self.handle_snapshot_delete(initial_state) yield if (deletion_policy != RETAIN and callable( getattr(self, 'check_delete_complete', None))): while not self.check_delete_complete(handle_data): yield except Exception as ex: logger.exception(_('Delete %s'), str(self)) failure = exception.ResourceFailure(ex, self, self.action) self.state_set(action, self.FAILED, str(failure)) raise failure except: with excutils.save_and_reraise_exception(): try: self.state_set(action, self.FAILED, 'Deletion aborted') except Exception: logger.exception( _('Error marking resource deletion ' 'failed')) else: self.state_set(action, self.COMPLETE) @scheduler.wrappertask def destroy(self): ''' Delete the resource and remove it from the database. ''' yield self.delete() if self.id is None: return try: db_api.resource_get(self.context, self.id).delete() except exception.NotFound: # Don't fail on delete if the db entry has # not been created yet. pass self.id = None def resource_id_set(self, inst): self.resource_id = inst if self.id is not None: try: rs = db_api.resource_get(self.context, self.id) rs.update_and_save({'nova_instance': self.resource_id}) except Exception as ex: logger.warn(_('db error %s') % str(ex)) def _store(self): '''Create the resource in the database.''' metadata = self.metadata try: rs = { 'action': self.action, 'status': self.status, 'status_reason': self.status_reason, 'stack_id': self.stack.id, 'nova_instance': self.resource_id, 'name': self.name, 'rsrc_metadata': metadata, 'stack_name': self.stack.name } new_rs = db_api.resource_create(self.context, rs) self.id = new_rs.id self.stack.updated_time = datetime.utcnow() except Exception as ex: logger.error(_('DB error %s') % str(ex)) def _add_event(self, action, status, reason): '''Add a state change event to the database.''' ev = event.Event(self.context, self.stack, action, status, reason, self.resource_id, self.properties, self.name, self.type()) try: ev.store() except Exception as ex: logger.error(_('DB error %s') % str(ex)) def _store_or_update(self, action, status, reason): self.action = action self.status = status self.status_reason = reason if self.id is not None: try: rs = db_api.resource_get(self.context, self.id) rs.update_and_save({ 'action': self.action, 'status': self.status, 'status_reason': reason, 'stack_id': self.stack.id, 'nova_instance': self.resource_id }) self.stack.updated_time = datetime.utcnow() except Exception as ex: logger.error(_('DB error %s') % str(ex)) # store resource in DB on transition to CREATE_IN_PROGRESS # all other transistions (other than to DELETE_COMPLETE) # should be handled by the update_and_save above.. elif (action, status) in [(self.CREATE, self.IN_PROGRESS), (self.ADOPT, self.IN_PROGRESS)]: self._store() def _resolve_attribute(self, name): """ Default implementation; should be overridden by resources that expose attributes :param name: The attribute to resolve :returns: the resource attribute named key """ # By default, no attributes resolve pass def state_reset(self): """ Reset state to (INIT, COMPLETE) """ self.action = self.INIT self.status = self.COMPLETE def state_set(self, action, status, reason="state changed"): if action not in self.ACTIONS: raise ValueError(_("Invalid action %s") % action) if status not in self.STATUSES: raise ValueError(_("Invalid status %s") % status) old_state = (self.action, self.status) new_state = (action, status) self._store_or_update(action, status, reason) if new_state != old_state: self._add_event(action, status, reason) @property def state(self): '''Returns state, tuple of action, status.''' return (self.action, self.status) def FnGetRefId(self): ''' For the intrinsic function Ref. :results: the id or name of the resource. ''' if self.resource_id is not None: return unicode(self.resource_id) else: return unicode(self.name) def FnGetAtt(self, key): ''' For the intrinsic function Fn::GetAtt. :param key: the attribute key. :returns: the attribute value. ''' try: return self.attributes[key] except KeyError: raise exception.InvalidTemplateAttribute(resource=self.name, key=key) def FnBase64(self, data): ''' For the instrinsic function Fn::Base64. :param data: the input data. :returns: the Base64 representation of the input data. ''' return base64.b64encode(data) def signal(self, details=None): ''' signal the resource. Subclasses should provide a handle_signal() method to implement the signal, the base-class raise an exception if no handler is implemented. ''' def get_string_details(): if details is None: return 'No signal details provided' if isinstance(details, basestring): return details if isinstance(details, dict): if all(k in details for k in ('previous', 'current', 'reason')): # this is from Ceilometer. auto = '%(previous)s to %(current)s (%(reason)s)' % details return 'alarm state changed from %s' % auto elif 'state' in details: # this is from watchrule return 'alarm state changed to %(state)s' % details return 'Unknown' try: if self.action in (self.SUSPEND, self.DELETE): msg = _('Cannot signal resource during %s') % self.action raise Exception(msg) if not callable(getattr(self, 'handle_signal', None)): msg = (_('Resource %s is not able to receive a signal') % str(self)) raise Exception(msg) self._add_event('signal', self.status, get_string_details()) self.handle_signal(details) except Exception as ex: logger.exception( _('signal %(name)s : %(msg)s') % { 'name': str(self), 'msg': str(ex) }) failure = exception.ResourceFailure(ex, self) raise failure def handle_update(self, json_snippet=None, tmpl_diff=None, prop_diff=None): raise UpdateReplace(self.name) def metadata_update(self, new_metadata=None): ''' No-op for resources which don't explicitly override this method ''' if new_metadata: logger.warning( _("Resource %s does not implement metadata update") % self.name) @classmethod def resource_to_template(cls, resource_type): ''' :param resource_type: The resource type to be displayed in the template :returns: A template where the resource's properties_schema is mapped as parameters, and the resource's attributes_schema is mapped as outputs ''' (parameters, properties) = (Properties.schema_to_parameters_and_properties( cls.properties_schema)) resource_name = cls.__name__ return { 'HeatTemplateFormatVersion': '2012-12-12', 'Parameters': parameters, 'Resources': { resource_name: { 'Type': resource_type, 'Properties': properties } }, 'Outputs': Attributes.as_outputs(resource_name, cls) }
class InstanceGroup(stack_resource.StackResource): tags_schema = {'Key': {'Type': 'String', 'Required': True}, 'Value': {'Type': 'String', 'Required': True}} properties_schema = { 'AvailabilityZones': { 'Required': True, 'Type': 'List', 'Description': _('Not Implemented.')}, 'LaunchConfigurationName': { 'Required': True, 'Type': 'String', 'Description': _('Name of LaunchConfiguration resource.')}, 'Size': { 'Required': True, 'Type': 'Number', 'Description': _('Desired number of instances.')}, 'LoadBalancerNames': { 'Type': 'List', 'Description': _('List of LoadBalancer resources.')}, 'Tags': { 'Type': 'List', 'Schema': {'Type': 'Map', 'Schema': tags_schema}, 'Description': _('Tags to attach to this group.')} } update_allowed_keys = ('Properties', 'UpdatePolicy',) update_allowed_properties = ('Size', 'LaunchConfigurationName',) attributes_schema = { "InstanceList": _("A comma-delimited list of server ip addresses. " "(Heat extension).") } rolling_update_schema = { 'MinInstancesInService': properties.Schema(properties.NUMBER, default=0), 'MaxBatchSize': properties.Schema(properties.NUMBER, default=1), 'PauseTime': properties.Schema(properties.STRING, default='PT0S') } update_policy_schema = { 'RollingUpdate': properties.Schema(properties.MAP, schema=rolling_update_schema) } def __init__(self, name, json_snippet, stack): """ UpdatePolicy is currently only specific to InstanceGroup and AutoScalingGroup. Therefore, init is overridden to parse for the UpdatePolicy. """ super(InstanceGroup, self).__init__(name, json_snippet, stack) self.update_policy = Properties(self.update_policy_schema, self.t.get('UpdatePolicy', {}), parent_name=self.name) def validate(self): """ Add validation for update_policy """ super(InstanceGroup, self).validate() if self.update_policy: self.update_policy.validate() def get_instance_names(self): """Get a list of resource names of the instances in this InstanceGroup. Failed resources will be ignored. """ return sorted(x.name for x in self.get_instances()) def get_instances(self): """Get a set of all the instance resources managed by this group.""" return [resource for resource in self.nested().itervalues() if resource.state[1] != resource.FAILED] def handle_create(self): """Create a nested stack and add the initial resources to it.""" num_instances = int(self.properties['Size']) initial_template = self._create_template(num_instances) return self.create_with_template(initial_template, {}) def check_create_complete(self, task): """ When stack creation is done, update the load balancer. If any instances failed to be created, delete them. """ done = super(InstanceGroup, self).check_create_complete(task) if done: self._lb_reload() return done def handle_update(self, json_snippet, tmpl_diff, prop_diff): """ If Properties has changed, update self.properties, so we get the new values during any subsequent adjustment. """ if tmpl_diff: # parse update policy if 'UpdatePolicy' in tmpl_diff: self.update_policy = Properties( self.update_policy_schema, json_snippet.get('UpdatePolicy', {}), parent_name=self.name) if prop_diff: self.properties = Properties(self.properties_schema, json_snippet.get('Properties', {}), self.stack.resolve_runtime_data, self.name) # Get the current capacity, we may need to adjust if # Size has changed if 'Size' in prop_diff: inst_list = self.get_instances() if len(inst_list) != int(self.properties['Size']): self.resize(int(self.properties['Size'])) def _tags(self): """ Make sure that we add a tag that Ceilometer can pick up. These need to be prepended with 'metering.'. """ tags = self.properties.get('Tags') or [] for t in tags: if t['Key'].startswith('metering.'): # the user has added one, don't add another. return tags return tags + [{'Key': 'metering.groupname', 'Value': self.FnGetRefId()}] def handle_delete(self): return self.delete_nested() def _create_template(self, num_instances): """ Create a template with a number of instance definitions based on the launch configuration. """ conf_name = self.properties['LaunchConfigurationName'] conf = self.stack.resource_by_refid(conf_name) instance_definition = copy.deepcopy(conf.t) instance_definition['Type'] = 'AWS::EC2::Instance' instance_definition['Properties']['Tags'] = self._tags() if self.properties.get('VPCZoneIdentifier'): instance_definition['Properties']['SubnetId'] = \ self.properties['VPCZoneIdentifier'][0] # resolve references within the context of this stack. fully_parsed = self.stack.resolve_runtime_data(instance_definition) resources = {} for i in range(num_instances): resources["%s-%d" % (self.name, i)] = fully_parsed return {"Resources": resources} def resize(self, new_capacity): """ Resize the instance group to the new capacity. When shrinking, the newest instances will be removed. """ new_template = self._create_template(new_capacity) try: updater = self.update_with_template(new_template, {}) updater.run_to_completion() self.check_update_complete(updater) finally: # Reload the LB in any case, so it's only pointing at healthy # nodes. self._lb_reload() def _lb_reload(self): ''' Notify the LoadBalancer to reload its config to include the changes in instances we have just made. This must be done after activation (instance in ACTIVE state), otherwise the instances' IP addresses may not be available. ''' if self.properties['LoadBalancerNames']: id_list = [inst.FnGetRefId() for inst in self.get_instances()] for lb in self.properties['LoadBalancerNames']: lb_resource = self.stack[lb] if 'Instances' in lb_resource.properties_schema: lb_resource.json_snippet['Properties']['Instances'] = ( id_list) elif 'members' in lb_resource.properties_schema: lb_resource.json_snippet['Properties']['members'] = ( id_list) else: raise exception.Error( "Unsupported resource '%s' in LoadBalancerNames" % (lb,)) resolved_snippet = self.stack.resolve_static_data( lb_resource.json_snippet) scheduler.TaskRunner(lb_resource.update, resolved_snippet)() def FnGetRefId(self): return self.physical_resource_name() def _resolve_attribute(self, name): ''' heat extension: "InstanceList" returns comma delimited list of server ip addresses. ''' if name == 'InstanceList': return u','.join(inst.FnGetAtt('PublicIp') for inst in self.get_instances()) or None
class Resource(object): ACTIONS = (INIT, CREATE, DELETE, UPDATE, ROLLBACK, SUSPEND, RESUME) = ( "INIT", "CREATE", "DELETE", "UPDATE", "ROLLBACK", "SUSPEND", "RESUME", ) STATUSES = (IN_PROGRESS, FAILED, COMPLETE) = ("IN_PROGRESS", "FAILED", "COMPLETE") # If True, this resource must be created before it can be referenced. strict_dependency = True created_time = timestamp.Timestamp(db_api.resource_get, "created_at") updated_time = timestamp.Timestamp(db_api.resource_get, "updated_at") _metadata = Metadata() # Resource implementation set this to the subset of template keys # which are supported for handle_update, used by update_template_diff update_allowed_keys = () # Resource implementation set this to the subset of resource properties # supported for handle_update, used by update_template_diff_properties update_allowed_properties = () # Resource implementations set this to the name: description dictionary # that describes the appropriate resource attributes attributes_schema = {} # If True, this resource may perform authenticated API requests # throughout its lifecycle requires_deferred_auth = False # Limit to apply to physical_resource_name() size reduction algorithm. # If set to None no limit will be applied. physical_resource_name_limit = 255 support_status = SupportStatus() def __new__(cls, name, json, stack): """Create a new Resource of the appropriate class for its type.""" if cls != Resource: # Call is already for a subclass, so pass it through return super(Resource, cls).__new__(cls) # Select the correct subclass to instantiate ResourceClass = stack.env.get_class(json["Type"], resource_name=name) return ResourceClass(name, json, stack) def __init__(self, name, json_snippet, stack): if "/" in name: raise ValueError(_('Resource name may not contain "/"')) self.stack = stack self.context = stack.context self.name = name self.json_snippet = json_snippet self.t = stack.resolve_static_data(json_snippet) self.properties = Properties( self.properties_schema, self.t.get("Properties", {}), self._resolve_runtime_data, self.name ) self.attributes = Attributes(self.name, self.attributes_schema, self._resolve_attribute) resource = db_api.resource_get_by_name_and_stack(self.context, name, stack.id) if resource: self.resource_id = resource.nova_instance self.action = resource.action self.status = resource.status self.status_reason = resource.status_reason self.id = resource.id self.data = resource.data else: self.resource_id = None # if the stack is being deleted, assume we've already been deleted if stack.action == stack.DELETE: self.action = self.DELETE else: self.action = self.INIT self.status = self.COMPLETE self.status_reason = "" self.id = None self.data = [] def __eq__(self, other): """Allow == comparison of two resources.""" # For the purposes of comparison, we declare two resource objects # equal if their names and parsed_templates are the same if isinstance(other, Resource): return (self.name == other.name) and (self.parsed_template() == other.parsed_template()) return NotImplemented def __ne__(self, other): """Allow != comparison of two resources.""" result = self.__eq__(other) if result is NotImplemented: return result return not result @property def metadata(self): return self._metadata @metadata.setter def metadata(self, metadata): self._metadata = metadata def type(self): return self.t["Type"] def _resolve_runtime_data(self, snippet): return self.stack.resolve_runtime_data(snippet) def has_interface(self, resource_type): """Check to see if this resource is either mapped to resource_type or is a "resource_type". """ if self.type() == resource_type: return True ri = self.stack.env.get_resource_info(self.type(), self.name) return ri.name == resource_type def identifier(self): """Return an identifier for this resource.""" return identifier.ResourceIdentifier(resource_name=self.name, **self.stack.identifier()) def parsed_template(self, section=None, default={}): """ Return the parsed template data for the resource. May be limited to only one section of the data, in which case a default value may also be supplied. """ if section is None: template = self.t else: template = self.t.get(section, default) return self._resolve_runtime_data(template) def update_template_diff(self, after, before): """ Returns the difference between the before and after json snippets. If something has been removed in after which exists in before we set it to None. If any keys have changed which are not in update_allowed_keys, raises UpdateReplace if the differing keys are not in update_allowed_keys """ update_allowed_set = set(self.update_allowed_keys) # Create a set containing the keys in both current and update template template_keys = set(before.keys()) template_keys.update(set(after.keys())) # Create a set of keys which differ (or are missing/added) changed_keys_set = set([k for k in template_keys if before.get(k) != after.get(k)]) if not changed_keys_set.issubset(update_allowed_set): badkeys = changed_keys_set - update_allowed_set raise UpdateReplace(self.name) return dict((k, after.get(k)) for k in changed_keys_set) def update_template_diff_properties(self, after, before): """ Returns the changed Properties between the before and after json snippets. If a property has been removed in after which exists in before we set it to None. If any properties have changed which are not in update_allowed_properties, raises UpdateReplace if the modified properties are not in the update_allowed_properties """ update_allowed_set = set(self.update_allowed_properties) for (psk, psv) in self.properties.props.iteritems(): if psv.update_allowed(): update_allowed_set.add(psk) # Create a set containing the keys in both current and update template current_properties = before.get("Properties", {}) template_properties = set(current_properties.keys()) updated_properties = after.get("Properties", {}) template_properties.update(set(updated_properties.keys())) # Create a set of keys which differ (or are missing/added) changed_properties_set = set( k for k in template_properties if current_properties.get(k) != updated_properties.get(k) ) if not changed_properties_set.issubset(update_allowed_set): raise UpdateReplace(self.name) return dict((k, updated_properties.get(k)) for k in changed_properties_set) def __str__(self): return '%s "%s"' % (self.__class__.__name__, self.name) def _add_dependencies(self, deps, path, fragment): if isinstance(fragment, dict): for key, value in fragment.items(): if key in ("DependsOn", "Ref", "Fn::GetAtt", "get_attr", "get_resource"): if key in ("Fn::GetAtt", "get_attr"): res_name, att = value res_list = [res_name] elif key == "DependsOn" and isinstance(value, list): res_list = value else: res_list = [value] for res in res_list: try: target = self.stack[res] except KeyError: raise exception.InvalidTemplateReference(resource=res, key=path) if key == "DependsOn" or target.strict_dependency: deps += (self, target) else: self._add_dependencies(deps, "%s.%s" % (path, key), value) elif isinstance(fragment, list): for index, item in enumerate(fragment): self._add_dependencies(deps, "%s[%d]" % (path, index), item) def add_dependencies(self, deps): self._add_dependencies(deps, self.name, self.t) deps += (self, None) def required_by(self): """ Returns a list of names of resources which directly require this resource as a dependency. """ return list([r.name for r in self.stack.dependencies.required_by(self)]) def keystone(self): return self.stack.clients.keystone() def nova(self, service_type="compute"): return self.stack.clients.nova(service_type) def swift(self): return self.stack.clients.swift() def neutron(self): return self.stack.clients.neutron() def cinder(self): return self.stack.clients.cinder() def trove(self): return self.stack.clients.trove() def ceilometer(self): return self.stack.clients.ceilometer() def heat(self): return self.stack.clients.heat() def _do_action(self, action, pre_func=None): """ Perform a transition to a new state via a specified action action should be e.g self.CREATE, self.UPDATE etc, we set status based on this, the transistion is handled by calling the corresponding handle_* and check_*_complete functions Note pre_func is an optional function reference which will be called before the handle_<action> function If the resource does not declare a check_$action_complete function, we declare COMPLETE status as soon as the handle_$action call has finished, and if no handle_$action function is declared, then we do nothing, useful e.g if the resource requires no action for a given state transition """ assert action in self.ACTIONS, "Invalid action %s" % action try: self.state_set(action, self.IN_PROGRESS) action_l = action.lower() handle = getattr(self, "handle_%s" % action_l, None) check = getattr(self, "check_%s_complete" % action_l, None) if callable(pre_func): pre_func() handle_data = None if callable(handle): handle_data = handle() yield if callable(check): while not check(handle_data): yield except Exception as ex: logger.exception("%s : %s" % (action, str(self))) failure = exception.ResourceFailure(ex, self, action) self.state_set(action, self.FAILED, str(failure)) raise failure except: with excutils.save_and_reraise_exception(): try: self.state_set(action, self.FAILED, "%s aborted" % action) except Exception: logger.exception(_("Error marking resource as failed")) else: self.state_set(action, self.COMPLETE) def create(self): """ Create the resource. Subclasses should provide a handle_create() method to customise creation. """ action = self.CREATE if (self.action, self.status) != (self.INIT, self.COMPLETE): exc = exception.Error(_("State %s invalid for create") % str(self.state)) raise exception.ResourceFailure(exc, self, action) logger.info("creating %s" % str(self)) # Re-resolve the template, since if the resource Ref's # the AWS::StackId pseudo parameter, it will change after # the parser.Stack is stored (which is after the resources # are __init__'d, but before they are create()'d) self.t = self.stack.resolve_static_data(self.json_snippet) self.properties = Properties( self.properties_schema, self.t.get("Properties", {}), self._resolve_runtime_data, self.name ) return self._do_action(action, self.properties.validate) def set_deletion_policy(self, policy): self.t["DeletionPolicy"] = policy def get_abandon_data(self): return { "name": self.name, "resource_id": self.resource_id, "type": self.type(), "action": self.action, "status": self.status, "metadata": self.metadata, "resource_data": dict((r.key, r.value) for r in db_api.resource_data_get_all(self)), } def update(self, after, before=None): """ update the resource. Subclasses should provide a handle_update() method to customise update, the base-class handle_update will fail by default. """ action = self.UPDATE if before is None: before = self.parsed_template() elif before == after: return if (self.action, self.status) in ((self.CREATE, self.IN_PROGRESS), (self.UPDATE, self.IN_PROGRESS)): exc = Exception(_("Resource update already requested")) raise exception.ResourceFailure(exc, self, action) logger.info("updating %s" % str(self)) try: self.state_set(action, self.IN_PROGRESS) properties = Properties( self.properties_schema, after.get("Properties", {}), self._resolve_runtime_data, self.name ) properties.validate() tmpl_diff = self.update_template_diff(after, before) prop_diff = self.update_template_diff_properties(after, before) if callable(getattr(self, "handle_update", None)): handle_data = self.handle_update(after, tmpl_diff, prop_diff) yield if callable(getattr(self, "check_update_complete", None)): while not self.check_update_complete(handle_data): yield except UpdateReplace: with excutils.save_and_reraise_exception(): logger.debug(_("Resource %s update requires replacement") % self.name) except Exception as ex: logger.exception("update %s : %s" % (str(self), str(ex))) failure = exception.ResourceFailure(ex, self, action) self.state_set(action, self.FAILED, str(failure)) raise failure else: self.t = self.stack.resolve_static_data(after) self.state_set(action, self.COMPLETE) def suspend(self): """ Suspend the resource. Subclasses should provide a handle_suspend() method to implement suspend """ action = self.SUSPEND # Don't try to suspend the resource unless it's in a stable state if self.action == self.DELETE or self.status != self.COMPLETE: exc = exception.Error(_("State %s invalid for suspend") % str(self.state)) raise exception.ResourceFailure(exc, self, action) logger.info(_("suspending %s") % str(self)) return self._do_action(action) def resume(self): """ Resume the resource. Subclasses should provide a handle_resume() method to implement resume """ action = self.RESUME # Can't resume a resource unless it's SUSPEND_COMPLETE if self.state != (self.SUSPEND, self.COMPLETE): exc = exception.Error(_("State %s invalid for resume") % str(self.state)) raise exception.ResourceFailure(exc, self, action) logger.info(_("resuming %s") % str(self)) return self._do_action(action) def physical_resource_name(self): if self.id is None: return None name = "%s-%s-%s" % (self.stack.name, self.name, short_id.get_id(self.id)) if self.physical_resource_name_limit: name = self.reduce_physical_resource_name(name, self.physical_resource_name_limit) return name @staticmethod def reduce_physical_resource_name(name, limit): """ Reduce length of physical resource name to a limit. The reduced name will consist of the following: * the first 2 characters of the name * a hyphen * the end of the name, truncated on the left to bring the name length within the limit :param name: The name to reduce the length of :param limit: The max length limit :returns: A name whose length is less than or equal to the limit """ if len(name) <= limit: return name if limit < 4: raise ValueError(_("limit cannot be less than 4")) postfix_length = limit - 3 return name[0:2] + "-" + name[-postfix_length:] def validate(self): logger.info(_("Validating %s") % str(self)) self.validate_deletion_policy(self.t) return self.properties.validate() @classmethod def validate_deletion_policy(cls, template): deletion_policy = template.get("DeletionPolicy", DELETE) if deletion_policy not in DELETION_POLICY: msg = _("Invalid DeletionPolicy %s") % deletion_policy raise exception.StackValidationFailed(message=msg) elif deletion_policy == SNAPSHOT: if not callable(getattr(cls, "handle_snapshot_delete", None)): msg = _("Snapshot DeletionPolicy not supported") raise exception.StackValidationFailed(message=msg) def delete(self): """ Delete the resource. Subclasses should provide a handle_delete() method to customise deletion. """ action = self.DELETE if (self.action, self.status) == (self.DELETE, self.COMPLETE): return # No need to delete if the resource has never been created if self.action == self.INIT: return initial_state = self.state logger.info(_("deleting %s") % str(self)) try: self.state_set(action, self.IN_PROGRESS) deletion_policy = self.t.get("DeletionPolicy", DELETE) handle_data = None if deletion_policy == DELETE: if callable(getattr(self, "handle_delete", None)): handle_data = self.handle_delete() yield elif deletion_policy == SNAPSHOT: if callable(getattr(self, "handle_snapshot_delete", None)): handle_data = self.handle_snapshot_delete(initial_state) yield if deletion_policy != RETAIN and callable(getattr(self, "check_delete_complete", None)): while not self.check_delete_complete(handle_data): yield except Exception as ex: logger.exception(_("Delete %s"), str(self)) failure = exception.ResourceFailure(ex, self, self.action) self.state_set(action, self.FAILED, str(failure)) raise failure except: with excutils.save_and_reraise_exception(): try: self.state_set(action, self.FAILED, "Deletion aborted") except Exception: logger.exception(_("Error marking resource deletion " "failed")) else: self.state_set(action, self.COMPLETE) @scheduler.wrappertask def destroy(self): """ Delete the resource and remove it from the database. """ yield self.delete() if self.id is None: return try: db_api.resource_get(self.context, self.id).delete() except exception.NotFound: # Don't fail on delete if the db entry has # not been created yet. pass self.id = None def resource_id_set(self, inst): self.resource_id = inst if self.id is not None: try: rs = db_api.resource_get(self.context, self.id) rs.update_and_save({"nova_instance": self.resource_id}) except Exception as ex: logger.warn(_("db error %s") % str(ex)) def _store(self): """Create the resource in the database.""" metadata = self.metadata try: rs = { "action": self.action, "status": self.status, "status_reason": self.status_reason, "stack_id": self.stack.id, "nova_instance": self.resource_id, "name": self.name, "rsrc_metadata": metadata, "stack_name": self.stack.name, } new_rs = db_api.resource_create(self.context, rs) self.id = new_rs.id self.stack.updated_time = datetime.utcnow() except Exception as ex: logger.error(_("DB error %s") % str(ex)) def _add_event(self, action, status, reason): """Add a state change event to the database.""" ev = event.Event( self.context, self.stack, action, status, reason, self.resource_id, self.properties, self.name, self.type() ) try: ev.store() except Exception as ex: logger.error(_("DB error %s") % str(ex)) def _store_or_update(self, action, status, reason): self.action = action self.status = status self.status_reason = reason if self.id is not None: try: rs = db_api.resource_get(self.context, self.id) rs.update_and_save( { "action": self.action, "status": self.status, "status_reason": reason, "stack_id": self.stack.id, "nova_instance": self.resource_id, } ) self.stack.updated_time = datetime.utcnow() except Exception as ex: logger.error(_("DB error %s") % str(ex)) # store resource in DB on transition to CREATE_IN_PROGRESS # all other transistions (other than to DELETE_COMPLETE) # should be handled by the update_and_save above.. elif (action, status) == (self.CREATE, self.IN_PROGRESS): self._store() def _resolve_attribute(self, name): """ Default implementation; should be overridden by resources that expose attributes :param name: The attribute to resolve :returns: the resource attribute named key """ # By default, no attributes resolve pass def state_reset(self): """ Reset state to (INIT, COMPLETE) """ self.action = self.INIT self.status = self.COMPLETE def state_set(self, action, status, reason="state changed"): if action not in self.ACTIONS: raise ValueError(_("Invalid action %s") % action) if status not in self.STATUSES: raise ValueError(_("Invalid status %s") % status) old_state = (self.action, self.status) new_state = (action, status) self._store_or_update(action, status, reason) if new_state != old_state: self._add_event(action, status, reason) @property def state(self): """Returns state, tuple of action, status.""" return (self.action, self.status) def FnGetRefId(self): """ For the intrinsic function Ref. :results: the id or name of the resource. """ if self.resource_id is not None: return unicode(self.resource_id) else: return unicode(self.name) def FnGetAtt(self, key): """ For the intrinsic function Fn::GetAtt. :param key: the attribute key. :returns: the attribute value. """ try: return self.attributes[key] except KeyError: raise exception.InvalidTemplateAttribute(resource=self.name, key=key) def FnBase64(self, data): """ For the instrinsic function Fn::Base64. :param data: the input data. :returns: the Base64 representation of the input data. """ return base64.b64encode(data) def signal(self, details=None): """ signal the resource. Subclasses should provide a handle_signal() method to implement the signal, the base-class raise an exception if no handler is implemented. """ def get_string_details(): if details is None: return "No signal details provided" if isinstance(details, basestring): return details if isinstance(details, dict): if all(k in details for k in ("previous", "current", "reason")): # this is from Ceilometer. auto = "%(previous)s to %(current)s (%(reason)s)" % details return "alarm state changed from %s" % auto elif "state" in details: # this is from watchrule return "alarm state changed to %(state)s" % details return "Unknown" try: if self.action in (self.SUSPEND, self.DELETE): msg = _("Cannot signal resource during %s") % self.action raise Exception(msg) if not callable(getattr(self, "handle_signal", None)): msg = _("Resource %s is not able to receive a signal") % str(self) raise Exception(msg) self._add_event("signal", self.status, get_string_details()) self.handle_signal(details) except Exception as ex: logger.exception(_("signal %(name)s : %(msg)s") % {"name": str(self), "msg": str(ex)}) failure = exception.ResourceFailure(ex, self) raise failure def handle_update(self, json_snippet=None, tmpl_diff=None, prop_diff=None): raise UpdateReplace(self.name) def metadata_update(self, new_metadata=None): """ No-op for resources which don't explicitly override this method """ if new_metadata: logger.warning(_("Resource %s does not implement metadata update") % self.name) @classmethod def resource_to_template(cls, resource_type): """ :param resource_type: The resource type to be displayed in the template :returns: A template where the resource's properties_schema is mapped as parameters, and the resource's attributes_schema is mapped as outputs """ (parameters, properties) = Properties.schema_to_parameters_and_properties(cls.properties_schema) resource_name = cls.__name__ return { "Parameters": parameters, "Resources": {resource_name: {"Type": resource_type, "Properties": properties}}, "Outputs": Attributes.as_outputs(resource_name, cls), }