# Copyright (c) 2014 Hewlett-Packard Development Company, L.P. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or # implied. # See the License for the specific language governing permissions and # limitations under the License. from oslo_log import log as logging import oslo_messaging from oslo_service import service from osprofiler import profiler import six from heat.common import context from heat.common import exception from heat.common.i18n import _LE from heat.common.i18n import _LI from heat.common import messaging as rpc_messaging from heat.engine import resource from heat.engine import scheduler from heat.engine import stack as parser from heat.engine import sync_point from heat.objects import resource as resource_objects from heat.rpc import listener_client from heat.rpc import worker_client as rpc_client LOG = logging.getLogger(__name__) @profiler.trace_cls("rpc") class WorkerService(service.Service): """Service that has 'worker' actor in convergence. This service is dedicated to handle internal messages to the 'worker' (a.k.a. 'converger') actor in convergence. Messages on this bus will use the 'cast' rather than 'call' method to anycast the message to an engine that will handle it asynchronously. It won't wait for or expect replies from these messages. """ RPC_API_VERSION = '1.2' def __init__(self, host, topic, engine_id, thread_group_mgr): super(WorkerService, self).__init__() self.host = host self.topic = topic self.engine_id = engine_id self.thread_group_mgr = thread_group_mgr self._rpc_client = rpc_client.WorkerClient() self._rpc_server = None self.target = None def start(self): target = oslo_messaging.Target( version=self.RPC_API_VERSION, server=self.host, topic=self.topic) self.target = target LOG.info(_LI("Starting %(topic)s (%(version)s) in engine %(engine)s."), {'topic': self.topic, 'version': self.RPC_API_VERSION, 'engine': self.engine_id}) self._rpc_server = rpc_messaging.get_rpc_server(target, self) self._rpc_server.start() super(WorkerService, self).start() def stop(self): # Stop rpc connection at first for preventing new requests LOG.info(_LI("Stopping %(topic)s in engine %(engine)s."), {'topic': self.topic, 'engine': self.engine_id}) try: self._rpc_server.stop() self._rpc_server.wait() except Exception as e: LOG.error(_LE("%(topic)s is failed to stop, %(exc)s"), {'topic': self.topic, 'exc': e}) super(WorkerService, self).stop() def _try_steal_engine_lock(self, cnxt, resource_id): rs_obj = resource_objects.Resource.get_obj(cnxt, resource_id) if (rs_obj.engine_id != self.engine_id and rs_obj.engine_id is not None): if not listener_client.EngineListenerClient( rs_obj.engine_id).is_alive(cnxt): # steal the lock. rs_obj.update_and_save({'engine_id': None}) return True return False def _trigger_rollback(self, stack): LOG.info(_LI("Triggering rollback of %(stack_name)s %(action)s "), {'action': stack.action, 'stack_name': stack.name}) stack.rollback() def _handle_failure(self, cnxt, stack, failure_reason): updated = stack.state_set(stack.action, stack.FAILED, failure_reason) if not updated: return if (not stack.disable_rollback and stack.action in (stack.CREATE, stack.ADOPT, stack.UPDATE)): self._trigger_rollback(stack) else: stack.purge_db() def _handle_resource_failure(self, cnxt, stack_id, failure_reason): stack = parser.Stack.load(cnxt, stack_id=stack_id) self._handle_failure(cnxt, stack, failure_reason) def _handle_stack_timeout(self, cnxt, stack): failure_reason = u'Timed out' self._handle_failure(cnxt, stack, failure_reason) def _load_resource(self, cnxt, resource_id, resource_data, is_update): if is_update: cache_data = {in_data.get( 'name'): in_data for in_data in resource_data.values() if in_data is not None} else: # no data to resolve in cleanup phase cache_data = {} try: return resource.Resource.load(cnxt, resource_id, is_update, cache_data) except (exception.ResourceNotFound, exception.NotFound): pass # can be ignored return None, None, None def _do_check_resource(self, cnxt, current_traversal, tmpl, resource_data, is_update, rsrc, stack, adopt_stack_data): try: if is_update: try: check_resource_update(rsrc, tmpl.id, resource_data, self.engine_id, stack) except exception.UpdateReplace: new_res_id = rsrc.make_replacement(tmpl.id) LOG.info("Replacing resource with new id %s", new_res_id) rpc_data = sync_point.serialize_input_data(resource_data) self._rpc_client.check_resource(cnxt, new_res_id, current_traversal, rpc_data, is_update, adopt_stack_data) return False else: check_resource_cleanup(rsrc, tmpl.id, resource_data, self.engine_id, stack.time_remaining()) return True except exception.UpdateInProgress: if self._try_steal_engine_lock(cnxt, rsrc.id): rpc_data = sync_point.serialize_input_data(resource_data) self._rpc_client.check_resource(cnxt, rsrc.id, current_traversal, rpc_data, is_update, adopt_stack_data) except exception.ResourceFailure as ex: reason = 'Resource %s failed: %s' % (rsrc.action, six.text_type(ex)) self._handle_resource_failure(cnxt, stack.id, reason) except scheduler.Timeout: # reload the stack to verify current traversal stack = parser.Stack.load(cnxt, stack_id=stack.id) if stack.current_traversal != current_traversal: return self._handle_stack_timeout(cnxt, stack) return False def _retrigger_check_resource(self, cnxt, is_update, resource_id, stack): current_traversal = stack.current_traversal graph = stack.convergence_dependencies.graph() key = (resource_id, is_update) predecessors = graph[key] def do_check(target_key, data): self.check_resource(resource_id, current_traversal, data) try: sync_point.sync(cnxt, resource_id, current_traversal, is_update, do_check, predecessors, {key: None}) except sync_point.SyncPointNotFound: pass def _initiate_propagate_resource(self, cnxt, resource_id, current_traversal, is_update, rsrc, stack): deps = stack.convergence_dependencies graph = deps.graph() graph_key = (resource_id, is_update) if graph_key not in graph and rsrc.replaces is not None: # If we are a replacement, impersonate the replaced resource for # the purposes of calculating whether subsequent resources are # ready, since everybody has to work from the same version of the # graph. Our real resource ID is sent in the input_data, so the # dependencies will get updated to point to this resource in time # for the next traversal. graph_key = (rsrc.replaces, is_update) def _get_input_data(req, fwd): if fwd: return construct_input_data(rsrc, stack) else: # Don't send data if initiating clean-up for self i.e. # initiating delete of a replaced resource if req not in graph_key: # send replaced resource as needed_by if it exists return (rsrc.replaced_by if rsrc.replaced_by is not None else resource_id) return None try: for req, fwd in deps.required_by(graph_key): input_data = _get_input_data(req, fwd) propagate_check_resource( cnxt, self._rpc_client, req, current_traversal, set(graph[(req, fwd)]), graph_key, input_data, fwd, stack.adopt_stack_data) check_stack_complete(cnxt, stack, current_traversal, resource_id, deps, is_update) except sync_point.SyncPointNotFound: # Reload the stack to determine the current traversal, and check # the SyncPoint for the current node to determine if it is ready. # If it is, then retrigger the current node with the appropriate # data for the latest traversal. stack = parser.Stack.load(cnxt, stack_id=rsrc.stack.id) if current_traversal == stack.current_traversal: LOG.debug('[%s] Traversal sync point missing.', current_traversal) return self._retrigger_check_resource(cnxt, is_update, resource_id, stack) @context.request_context def check_resource(self, cnxt, resource_id, current_traversal, data, is_update, adopt_stack_data): """Process a node in the dependency graph. The node may be associated with either an update or a cleanup of its associated resource. """ resource_data = dict(sync_point.deserialize_input_data(data)) rsrc, rsrc_owning_stack, stack = self._load_resource(cnxt, resource_id, resource_data, is_update) if rsrc is None: return if current_traversal != stack.current_traversal: LOG.debug('[%s] Traversal cancelled; stopping.', current_traversal) return if stack.has_timed_out(): self._handle_stack_timeout(cnxt, stack) return tmpl = stack.t stack.adopt_stack_data = adopt_stack_data if is_update: if (rsrc.replaced_by is not None and rsrc.current_template_id != tmpl.id): return check_resource_done = self._do_check_resource(cnxt, current_traversal, tmpl, resource_data, is_update, rsrc, stack, adopt_stack_data) if check_resource_done: # initiate check on next set of resources from graph self._initiate_propagate_resource(cnxt, resource_id, current_traversal, is_update, rsrc, stack) def construct_input_data(rsrc, curr_stack): attributes = curr_stack.get_dep_attrs( six.itervalues(curr_stack.resources), curr_stack.outputs, rsrc.name) resolved_attributes = {} for attr in attributes: try: if isinstance(attr, six.string_types): resolved_attributes[attr] = rsrc.FnGetAtt(attr) else: resolved_attributes[attr] = rsrc.FnGetAtt(*attr) except exception.InvalidTemplateAttribute as ita: LOG.info(six.text_type(ita)) input_data = {'id': rsrc.id, 'name': rsrc.name, 'reference_id': rsrc.FnGetRefId(), 'attrs': resolved_attributes, 'status': rsrc.status, 'action': rsrc.action, 'uuid': rsrc.uuid} return input_data def check_stack_complete(cnxt, stack, current_traversal, sender_id, deps, is_update): """Mark the stack complete if the update is complete. Complete is currently in the sense that all desired resources are in service, not that superfluous ones have been cleaned up. """ roots = set(deps.roots()) if (sender_id, is_update) not in roots: return def mark_complete(stack_id, data): stack.mark_complete() sender_key = (sender_id, is_update) sync_point.sync(cnxt, stack.id, current_traversal, True, mark_complete, roots, {sender_key: None}) def propagate_check_resource(cnxt, rpc_client, next_res_id, current_traversal, predecessors, sender_key, sender_data, is_update, adopt_stack_data): """Trigger processing of node if all of its dependencies are satisfied.""" def do_check(entity_id, data): rpc_client.check_resource(cnxt, entity_id, current_traversal, data, is_update, adopt_stack_data) sync_point.sync(cnxt, next_res_id, current_traversal, is_update, do_check, predecessors, {sender_key: sender_data}) def check_resource_update(rsrc, template_id, resource_data, engine_id, stack): """Create or update the Resource if appropriate.""" if rsrc.action == resource.Resource.INIT: rsrc.create_convergence(template_id, resource_data, engine_id, stack.time_remaining()) else: rsrc.update_convergence(template_id, resource_data, engine_id, stack.time_remaining(), stack) def check_resource_cleanup(rsrc, template_id, resource_data, engine_id, timeout): """Delete the Resource if appropriate.""" rsrc.delete_convergence(template_id, resource_data, engine_id, timeout)