def start(self): log.debug("GovernanceController starting ...") self._CFG = CFG self.enabled = CFG.get_safe('interceptor.interceptors.governance.config.enabled', False) if not self.enabled: log.warn("GovernanceInterceptor disabled by configuration") self.policy_event_subscriber = None # Containers default to not Org Boundary and ION Root Org self._is_container_org_boundary = CFG.get_safe('container.org_boundary', False) self._container_org_name = CFG.get_safe('container.org_name', CFG.get_safe('system.root_org', 'ION')) self._container_org_id = None self._system_root_org_name = CFG.get_safe('system.root_org', 'ION') self._is_root_org_container = (self._container_org_name == self._system_root_org_name) self.system_actor_id = None self.system_actor_user_header = None self.rr_client = ResourceRegistryServiceProcessClient(process=self.container) self.policy_client = PolicyManagementServiceProcessClient(process=self.container) if self.enabled: config = CFG.get_safe('interceptor.interceptors.governance.config') self.initialize_from_config(config) self.policy_event_subscriber = EventSubscriber(event_type=OT.PolicyEvent, callback=self.policy_event_callback) self.policy_event_subscriber.start() self._policy_snapshot = self._get_policy_snapshot() self._log_policy_update("start_governance_ctrl", message="Container start")
def op_load_system_policies(cls, calling_process): """ Create the initial set of policy rules for the system. To establish clear rule precedence, denying all anonymous access to Org services first and then add rules which Permit access to specific operations based on conditions. """ orgms_client = OrgManagementServiceProcessClient(process=calling_process) policyms_client = PolicyManagementServiceProcessClient(process=calling_process) ion_org = orgms_client.find_org() system_actor = get_system_actor() log.info('System actor: %s', system_actor._id) sa_user_header = get_system_actor_header(system_actor) policy_rules_filename = calling_process.CFG.get_safe("bootstrap.initial_policy_rules") if not policy_rules_filename: raise ContainerConfigError("Policy rules file not configured") if not os.path.exists(policy_rules_filename): raise ContainerConfigError("Policy rules file does not exist") with open(policy_rules_filename, "r") as f: policy_rules_yml = f.read() policy_rules_cfg = yaml.safe_load(policy_rules_yml) if "type" not in policy_rules_cfg or policy_rules_cfg["type"] != "scioncc_policy_rules": raise ContainerConfigError("Invalid policy rules file content") log.info("Loading %s policy rules", len(policy_rules_cfg["rules"])) for rule_cfg in policy_rules_cfg["rules"]: rule_name, policy_type, rule_desc = rule_cfg["name"], rule_cfg["policy_type"], rule_cfg.get("description", "") if rule_cfg.get("enable") is False: log.info("Policy rule %s disabled", rule_name) continue log.info("Loading policy rule %s (%s)", rule_name, policy_type) rule_filename = rule_cfg["rule_def"] if not os.path.isabs(rule_filename): rule_filename = os.path.join(os.path.dirname(policy_rules_filename), rule_filename) with open(rule_filename, "r") as f: rule_def = f.read() ordinal = rule_cfg.get("ordinal", 0) # Create the policy if policy_type == "common_service_access": policyms_client.create_common_service_access_policy(rule_name, rule_desc, rule_def, ordinal=ordinal, headers=sa_user_header) elif policy_type == "service_access": service_name = rule_cfg["service_name"] policyms_client.create_service_access_policy(service_name, rule_name, rule_desc, rule_def, ordinal=ordinal, headers=sa_user_header) elif policy_type == "resource_access": resource_type, resource_name = rule_cfg["resource_type"], rule_cfg["resource_name"] res_ids, _ = calling_process.container.resource_registry.find_resources( restype=resource_type, name=resource_name, id_only=True) if res_ids: resource_id = res_ids[0] policyms_client.create_resource_access_policy(resource_id, rule_name, rule_desc, rule_def, ordinal=ordinal, headers=sa_user_header) else: raise ContainerConfigError("Rule %s has invalid policy type: %s" % (rule_name, policy_type))
def start(self): log.debug("GovernanceController starting ...") self._CFG = CFG self.enabled = CFG.get_safe( 'interceptor.interceptors.governance.config.enabled', False) if not self.enabled: log.warn("GovernanceInterceptor disabled by configuration") self.policy_event_subscriber = None # Containers default to not Org Boundary and ION Root Org self._is_container_org_boundary = CFG.get_safe( 'container.org_boundary', False) self._container_org_name = CFG.get_safe( 'container.org_name', CFG.get_safe('system.root_org', 'ION')) self._container_org_id = None self._system_root_org_name = CFG.get_safe('system.root_org', 'ION') self._is_root_org_container = ( self._container_org_name == self._system_root_org_name) self.system_actor_id = None self.system_actor_user_header = None self.rr_client = ResourceRegistryServiceProcessClient( process=self.container) self.policy_client = PolicyManagementServiceProcessClient( process=self.container) if self.enabled: config = CFG.get_safe('interceptor.interceptors.governance.config') self.initialize_from_config(config) self.policy_event_subscriber = EventSubscriber( event_type=OT.PolicyEvent, callback=self.policy_event_callback) self.policy_event_subscriber.start() self._policy_snapshot = self._get_policy_snapshot() self._log_policy_update("start_governance_ctrl", message="Container start")
def op_load_system_policies(cls, calling_process): """ Create the initial set of policy rules for the system. To establish clear rule precedence, denying all anonymous access to Org services first and then add rules which Permit access to specific operations based on conditions. """ orgms_client = OrgManagementServiceProcessClient( process=calling_process) policyms_client = PolicyManagementServiceProcessClient( process=calling_process) ion_org = orgms_client.find_org() system_actor = get_system_actor() log.info('System actor: %s', system_actor._id) sa_user_header = get_system_actor_header(system_actor) policy_rules_filename = calling_process.CFG.get_safe( "bootstrap.initial_policy_rules") if not policy_rules_filename: raise ContainerConfigError("Policy rules file not configured") if not os.path.exists(policy_rules_filename): raise ContainerConfigError("Policy rules file does not exist") with open(policy_rules_filename, "r") as f: policy_rules_yml = f.read() policy_rules_cfg = yaml.safe_load(policy_rules_yml) if "type" not in policy_rules_cfg or policy_rules_cfg[ "type"] != "scioncc_policy_rules": raise ContainerConfigError("Invalid policy rules file content") log.info("Loading %s policy rules", len(policy_rules_cfg["rules"])) for rule_cfg in policy_rules_cfg["rules"]: rule_name, policy_type, rule_desc = rule_cfg["name"], rule_cfg[ "policy_type"], rule_cfg.get("description", "") if rule_cfg.get("enable") is False: log.info("Policy rule %s disabled", rule_name) continue log.info("Loading policy rule %s (%s)", rule_name, policy_type) rule_filename = rule_cfg["rule_def"] if not os.path.isabs(rule_filename): rule_filename = os.path.join( os.path.dirname(policy_rules_filename), rule_filename) with open(rule_filename, "r") as f: rule_def = f.read() ordinal = rule_cfg.get("ordinal", 0) # Create the policy if policy_type == "common_service_access": policyms_client.create_common_service_access_policy( rule_name, rule_desc, rule_def, ordinal=ordinal, headers=sa_user_header) elif policy_type == "service_access": service_name = rule_cfg["service_name"] policyms_client.create_service_access_policy( service_name, rule_name, rule_desc, rule_def, ordinal=ordinal, headers=sa_user_header) elif policy_type == "resource_access": resource_type, resource_name = rule_cfg[ "resource_type"], rule_cfg["resource_name"] res_ids, _ = calling_process.container.resource_registry.find_resources( restype=resource_type, name=resource_name, id_only=True) if res_ids: resource_id = res_ids[0] policyms_client.create_resource_access_policy( resource_id, rule_name, rule_desc, rule_def, ordinal=ordinal, headers=sa_user_header) else: raise ContainerConfigError( "Rule %s has invalid policy type: %s" % (rule_name, policy_type))
class GovernanceController(object): """ This is a singleton object which handles governance functionality in the container. Registers event callback for PolicyEvent to update local policies on change. """ def __init__(self, container): log.debug('GovernanceController.__init__()') self.container = container self.enabled = False self.interceptor_by_name_dict = {} self.interceptor_order = [] self.policy_decision_point_manager = None self.governance_dispatcher = None # Holds a list per service operation of policy methods to be called before operation is invoked self._service_op_preconditions = {} # Holds a list per process operation of policy methods to be called before operation is invoked self._process_op_preconditions = {} self._is_container_org_boundary = False self._container_org_name = None self._container_org_id = None # For policy debugging purposes. Keeps a list of most recent policy updates for later readout self._policy_update_log = [] self._policy_snapshot = None def start(self): log.debug("GovernanceController starting ...") self._CFG = CFG self.enabled = CFG.get_safe('interceptor.interceptors.governance.config.enabled', False) if not self.enabled: log.warn("GovernanceInterceptor disabled by configuration") self.policy_event_subscriber = None # Containers default to not Org Boundary and ION Root Org self._is_container_org_boundary = CFG.get_safe('container.org_boundary', False) self._container_org_name = CFG.get_safe('container.org_name', CFG.get_safe('system.root_org', 'ION')) self._container_org_id = None self._system_root_org_name = CFG.get_safe('system.root_org', 'ION') self._is_root_org_container = (self._container_org_name == self._system_root_org_name) self.system_actor_id = None self.system_actor_user_header = None self.rr_client = ResourceRegistryServiceProcessClient(process=self.container) self.policy_client = PolicyManagementServiceProcessClient(process=self.container) if self.enabled: config = CFG.get_safe('interceptor.interceptors.governance.config') self.initialize_from_config(config) self.policy_event_subscriber = EventSubscriber(event_type=OT.PolicyEvent, callback=self.policy_event_callback) self.policy_event_subscriber.start() self._policy_snapshot = self._get_policy_snapshot() self._log_policy_update("start_governance_ctrl", message="Container start") def initialize_from_config(self, config): self.governance_dispatcher = GovernanceDispatcher() self.policy_decision_point_manager = PolicyDecisionPointManager(self) self.interceptor_order = config.get('interceptor_order', None) or [] gov_ints = config.get('governance_interceptors', None) or {} for name in gov_ints: interceptor_def = gov_ints[name] classobj = named_any(interceptor_def["class"]) classinst = classobj() self.interceptor_by_name_dict[name] = classinst def _ensure_system_actor(self): """Make sure we have a handle for the system actor""" if self.system_actor_id is None: system_actor = get_system_actor() if system_actor is not None: self.system_actor_id = system_actor._id self.system_actor_user_header = get_system_actor_header(system_actor) def stop(self): log.debug("GovernanceController stopping ...") if self.policy_event_subscriber is not None: self.policy_event_subscriber.stop() @property def is_container_org_boundary(self): return self._is_container_org_boundary @property def container_org_name(self): return self._container_org_name @property def system_root_org_name(self): return self._system_root_org_name @property def is_root_org_container(self): return self._is_root_org_container @property def CFG(self): return self._CFG @property def rr(self): """Returns the active resource registry instance if available in the container or service client. """ if self.container.has_capability('RESOURCE_REGISTRY'): return self.container.resource_registry return self.rr_client def get_container_org_boundary_id(self): """Returns the permanent org identifier configured for this container """ if not self._is_container_org_boundary: return None if self._container_org_id is None: org_ids, _ = self.rr.find_resources_ext(restype=RT.Org, attr_name="org_governance_name", attr_value=self._container_org_name, id_only=True) if org_ids: self._container_org_id = org_ids[0] return self._container_org_id # --- Interceptor management def process_incoming_message(self, invocation): """The GovernanceController hook into the incoming message interceptor stack """ self.process_message(invocation, self.interceptor_order, Invocation.PATH_IN) return self.governance_dispatcher.handle_incoming_message(invocation) def process_outgoing_message(self, invocation): """The GovernanceController hook into the outgoing message interceptor stack """ self.process_message(invocation, reversed(self.interceptor_order), Invocation.PATH_OUT) return self.governance_dispatcher.handle_outgoing_message(invocation) def process_message(self, invocation, interceptor_list, method): """ The GovernanceController hook to iterate over the interceptors to call each one and evaluate the annotations to see what actions should be done. """ for int_name in interceptor_list: interceptor_obj = self.interceptor_by_name_dict[int_name] interceptor_func = getattr(interceptor_obj, method) # Invoke interceptor function for designated path interceptor_func(invocation) # Stop processing message if an issue with the message was found by an interceptor if invocation.message_annotations.get(GovernanceDispatcher.CONVERSATION__STATUS_ANNOTATION, None) == GovernanceDispatcher.STATUS_REJECT or \ invocation.message_annotations.get(GovernanceDispatcher.POLICY__STATUS_ANNOTATION, None) == GovernanceDispatcher.STATUS_REJECT: break return invocation # --- Container policy management def policy_event_callback(self, policy_event, *args, **kwargs): """Generic policy event handler for dispatching policy related events. """ self._ensure_system_actor() log.info("Received policy event: %s", policy_event) if policy_event.type_ == OT.ResourcePolicyEvent: self.resource_policy_event_callback(policy_event, *args, **kwargs) elif policy_event.type_ == OT.RelatedResourcePolicyEvent: self.resource_policy_event_callback(policy_event, *args, **kwargs) elif policy_event.type_ == OT.ServicePolicyEvent: self.service_policy_event_callback(policy_event, *args, **kwargs) self._log_policy_update("policy_event_callback", message="Event processed", event=policy_event) def service_policy_event_callback(self, service_policy_event, *args, **kwargs): """The ServicePolicyEvent handler """ log.debug('Service policy event: %s', str(service_policy_event.__dict__)) policy_id = service_policy_event.origin service_name = service_policy_event.service_name service_op = service_policy_event.op delete_policy = True if service_policy_event.sub_type == 'DeletePolicy' else False if service_name: if self.container.proc_manager.is_local_service_process(service_name): self.update_service_access_policy(service_name, service_op, delete_policy=delete_policy) elif self.container.proc_manager.is_local_agent_process(service_name): self.update_service_access_policy(service_name, service_op, delete_policy=delete_policy) else: self.update_common_service_access_policy() def resource_policy_event_callback(self, resource_policy_event, *args, **kwargs): """The ResourcePolicyEvent handler """ log.debug('Resource policy event: %s', str(resource_policy_event.__dict__)) policy_id = resource_policy_event.origin resource_id = resource_policy_event.resource_id delete_policy = True if resource_policy_event.sub_type == 'DeletePolicy' else False self.update_resource_access_policy(resource_id, delete_policy) def reset_policy_cache(self): """Empty and reload the container's policy caches. Reload by getting policy for each of the container's processes and common policy. """ log.info('Resetting policy cache') # First remove all cached polices and operation precondition functions self._clear_container_policy_caches() # Load the common service access policies since they are shared across services self.update_common_service_access_policy() # Iterate over the processes running in the container and reload their policies proc_list = self.container.proc_manager.list_local_processes() for proc in proc_list: self.update_process_policies(proc, force_update=False) self._log_policy_update("reset_policy_cache") def _clear_container_policy_caches(self): self.policy_decision_point_manager.clear_policy_cache() self.unregister_all_process_policy_preconditions() def update_process_policies(self, process_instance, safe_mode=False, force_update=True): """ Load any applicable process policies for a container process. To be called by when spawning a new process, or when policy is reset. @param process_instance The ION process for which to load policy @param safe_mode If True, will not attempt to read policy if Policy MS not available """ # NOTE: During restart, we rely on the bootstrap code to remove registration of Policy MS if safe_mode and not self._is_policy_management_service_available(): if not is_testing() and (process_instance.name not in {"resource_registry", "system_management", "directory", "identity_management"} and process_instance._proc_name != "event_persister"): # We are in the early phases of bootstrapping log.warn("update_process_policies(%s) - No update. Policy MS not available", process_instance._proc_name) self._log_policy_update("update_process_policies", message="No update. Policy MS not available", process=process_instance) return self._ensure_system_actor() if process_instance._proc_type == PROCTYPE_SERVICE: self.update_service_access_policy(process_instance._proc_listen_name, force_update=force_update) elif process_instance._proc_type == PROCTYPE_AGENT: # Load any existing policies for this agent with type or name if process_instance.resource_type is None: self.update_service_access_policy(process_instance.name, force_update=force_update) else: self.update_service_access_policy(process_instance.resource_type, force_update=force_update) if process_instance.resource_id: # Load any existing policies for this resource self.update_resource_access_policy(process_instance.resource_id, force_update=force_update) self._log_policy_update("update_process_policies", message="Checked", process=process_instance) def update_common_service_access_policy(self, delete_policy=False): """Update policy common to all services""" if self.policy_decision_point_manager is None: return try: rules = self.policy_client.get_active_service_access_policy_rules( service_name='', org_name=self._container_org_name, headers=self.system_actor_user_header) self.policy_decision_point_manager.set_common_service_policy_rules(rules) except Exception as e: # If the resource does not exist, just ignore it - but log a warning. log.warn("There was an error applying access policy: %s" % e.message) def update_service_access_policy(self, service_name, service_op='', delete_policy=False, force_update=True): """Update policy for a service""" if self.policy_decision_point_manager is None: return if not force_update and not service_op and self.policy_decision_point_manager.has_service_policy(service_name): log.info("Skipping update of service %s policy - already cached", service_name) return try: if service_op: policies = self.policy_client.get_active_service_operation_preconditions( service_name=service_name, op=service_op, org_name=self._container_org_name, headers=self.system_actor_user_header) else: policies = self.policy_client.get_active_service_access_policy_rules( service_name=service_name, org_name=self._container_org_name, headers=self.system_actor_user_header) # First update any access policy rules svc_access_policy = [p for p in policies if p.policy_type in (PolicyTypeEnum.COMMON_SERVICE_ACCESS, PolicyTypeEnum.SERVICE_ACCESS)] self.policy_decision_point_manager.set_service_policy_rules(service_name, svc_access_policy) # Next update any precondition policies svc_preconditions = [p for p in policies if p.policy_type == PolicyTypeEnum.SERVICE_OP_PRECOND] # There can be several local processes for a service procs = self.container.proc_manager.get_local_service_processes(service_name) for proc in procs: if svc_preconditions: for op_pre_policy in svc_preconditions: for pre_check in op_pre_policy.preconditions: self.unregister_process_operation_precondition(proc, op_pre_policy.op, pre_check) if not delete_policy: self.register_process_operation_precondition(proc, op_pre_policy.op, pre_check) else: # Unregister all, just in case self.unregister_all_process_operation_precondition(proc, service_op) except Exception as ex: # If the resource does not exist, just ignore it - but log a warning. log.warn("Error applying access policy for service %s: %s" % (service_name, ex.message)) def update_resource_access_policy(self, resource_id, delete_policy=False, force_update=True): """Update policy for a resource (such as a device fronted by an agent process)""" if self.policy_decision_point_manager is None: return if self.policy_decision_point_manager.has_resource_policy(resource_id): return try: policy_list = self.policy_client.get_active_resource_access_policy_rules( resource_id, headers=self.system_actor_user_header) self.policy_decision_point_manager.set_resource_policy_rules(resource_id, policy_list) except Exception as e: # If the resource does not exist, just ignore it - but log a warning. log.warn("There was an error applying access policy for resource %s: %s", resource_id, e.message) def update_process_access_policy(self, process_key, service_op='', delete_policy=False, force_update=True): pass # procs, op_preconditions = [], None # try: # # There can be several local processes for a service all with different names # procs = self.container.proc_manager.get_local_service_processes(service_name) # if procs: # op_preconditions = self.policy_client.get_active_service_operation_preconditions( # service_name=service_name, op=service_op, org_name=self._container_org_name, # headers=self.system_actor_user_header) # except Exception as ex: # # If the resource does not exist, just ignore it - but log a warning. # log.warn("Error applying precondition access policy for service %s: %s" % (service_name, ex.message)) # # for proc in procs: # try: # if op_preconditions: # for op in op_preconditions: # for pre in op.preconditions: # self.unregister_process_operation_precondition(proc, op.op, pre) # if not delete_policy: # self.register_process_operation_precondition(proc, op.op, pre) # else: # # Unregister all, just in case # self.unregister_all_process_operation_precondition(proc, service_op) # except Exception as ex: # # If the resource does not exist, just ignore it - but log a warning. # log.warn("Error applying precondition access policy for process %s of service %s: %s" % (proc, service_name, ex.message)) def get_active_policies(self): container_policies = dict() container_policies['common_service_access'] = self.policy_decision_point_manager.load_common_service_pdp container_policies['service_access'] = {k: v for (k, v) in self.policy_decision_point_manager.service_policy_decision_point.iteritems() if v is not None} container_policies['resource_access'] = {k: v for (k, v) in self.policy_decision_point_manager.resource_policy_decision_point.iteritems() if v is not None} container_policies['service_operation'] = dict(self._service_op_preconditions) #log.info(container_policies) return container_policies def _is_policy_management_service_available(self): """ Method to verify if the Policy Management Service is running in the system. If the container cannot connect to the RR then assume it is remote container so do not try to access Policy Management Service """ policy_service = get_service_registry().is_service_available('policy_management', True) if policy_service: return True return False def _get_policy_snapshot(self): """Debugging helper that snapshot copies the current container's policy state. """ policy_snap = {} policy_snap["snap_ts"] = get_ion_ts() policies = self.get_active_policies() common_list = [] policy_snap["common_pdp"] = common_list for rule in policies.get("common_service_access", {}).policy.rules: rule_dict = dict(id=rule.id, description=rule.description, effect=rule.effect.value) common_list.append(rule_dict) service_dict = {} policy_snap["service_pdp"] = service_dict for (svc_name, sp) in policies.get("service_access", {}).iteritems(): for rule in sp.policy.rules: if svc_name not in service_dict: service_dict[svc_name] = [] rule_dict = dict(id=rule.id, description=rule.description, effect=rule.effect.value) service_dict[svc_name].append(rule_dict) service_pre_dict = {} policy_snap["service_precondition"] = service_pre_dict for (svc_name, sp) in policies.get("service_operation", {}).iteritems(): for op, f in sp.iteritems(): if svc_name not in service_pre_dict: service_pre_dict[svc_name] = [] service_pre_dict[svc_name].append(op) resource_dict = {} policy_snap["resource_pdp"] = resource_dict for (res_name, sp) in policies.get("resource_access", {}).iteritems(): for rule in sp.policy.rules: if res_name not in service_dict: resource_dict[res_name] = [] rule_dict = dict(id=rule.id, description=rule.description, effect=rule.effect.value) resource_dict[res_name].append(rule_dict) return policy_snap def _log_policy_update(self, update_type=None, message=None, event=None, process=None): policy_update_dict = {} policy_update_dict["update_ts"] = get_ion_ts() policy_update_dict["update_type"] = update_type or "" policy_update_dict["message"] = message or "" if event: policy_update_dict["event._id"] = getattr(event, "_id", "") policy_update_dict["event.ts_created"] = getattr(event, "ts_created", "") policy_update_dict["event.type_"] = getattr(event, "type_", "") policy_update_dict["event.sub_type"] = getattr(event, "sub_type", "") if process: policy_update_dict["proc._proc_name"] = getattr(process, "_proc_name", "") policy_update_dict["proc.name"] = getattr(process, "name", "") policy_update_dict["proc._proc_listen_name"] = getattr(process, "_proc_listen_name", "") policy_update_dict["proc.resource_type"] = getattr(process, "resource_type", "") policy_update_dict["proc.resource_id"] = getattr(process, "resource_id", "") any_change = False # Change can only be detected in number/names of policy not content snapshot = self._policy_snapshot policy_now = self._get_policy_snapshot() # Comparison of snapshot to current policy try: def compare_policy(pol_cur, pol_snap, key, res): pol_cur_set = {d["id"] if isinstance(d, dict) else d for d in pol_cur} pol_snap_set = {d["id"] if isinstance(d, dict) else d for d in pol_snap} if pol_cur_set != pol_snap_set: policy_update_dict["snap.%s.%s.added" % (key, res)] = pol_cur_set - pol_snap_set policy_update_dict["snap.%s.%s.removed" % (key, res)] = pol_snap_set - pol_cur_set log.debug("Policy changed for %s.%s: %s vs %s" % (key, res, pol_cur_set, pol_snap_set)) return True return False policy_update_dict["snap.snap_ts"] = snapshot["snap_ts"] for key in ("common_pdp", "service_pdp", "service_precondition", "resource_pdp"): pol_snap = snapshot[key] pol_cur = policy_now[key] if isinstance(pol_cur, dict): for res in pol_cur.keys(): pol_list = pol_cur[res] snap_list = pol_snap.get(res, []) any_change = compare_policy(pol_list, snap_list, key, res) or any_change elif isinstance(pol_cur, list): any_change = compare_policy(pol_cur, pol_snap, key, "common") or any_change policy_update_dict["snap.policy_changed"] = str(any_change) except Exception as ex: log.warn("Cannot compare current policy to prior snapshot", exc_info=True) self._policy_update_log.append(policy_update_dict) self._policy_update_log = self._policy_update_log[-100:] self._policy_snapshot = policy_now if any_change: log.debug("Container policy changed. Cause: %s/%s" % (update_type, message)) else: log.debug("Container policy checked but no change. Cause: %s/%s" % (update_type, message)) # --- Methods for managing operation specific preconditions def get_process_operation_dict(self, process_name, auto_add=True): if process_name in self._service_op_preconditions: return self._service_op_preconditions[process_name] if auto_add: self._service_op_preconditions[process_name] = dict() return self._service_op_preconditions[process_name] return None def register_process_operation_precondition(self, process, operation, precondition): """ This method is used to register process operation precondition functions with the governance controller. The endpoint code will call check_process_operation_preconditions() below before calling the business logic operation and if any of the precondition functions return False, then the request is denied as Unauthorized. At some point, this should be refactored to by another interceptor, but at the operation level. """ if not hasattr(process, operation): raise NotFound("The operation %s does not exist for the %s process" % (operation, process.name)) if type(precondition) == types.MethodType and precondition.im_self != process: raise NotFound("The method %s does not exist for the %s process." % (str(precondition), process.name)) process_op_conditions = self.get_process_operation_dict(process.name) if operation in process_op_conditions: process_op_conditions[operation].append(precondition) else: preconditions = list() preconditions.append(precondition) process_op_conditions[operation] = preconditions def unregister_all_process_operation_precondition(self, process, operation): """ This method removes all precondition functions registered with an operation on a process. Care should be taken with this call, as it can remove "hard wired" preconditions that are directly registered by processes in a container. """ process_op_conditions = self.get_process_operation_dict(process.name, auto_add=False) if process_op_conditions is not None and operation in process_op_conditions: del process_op_conditions[operation] def unregister_process_operation_precondition(self, process, operation, precondition): """ This method removes a specific precondition function registered with an operation on a process. Care should be taken with this call, as it can remove "hard wired" preconditions that are directly registered by processes in a container. """ #Just skip this if there operation is not passed in. if operation is None: return if not hasattr(process, operation): raise NotFound("The operation %s does not exist for the %s service" % (operation, process.name)) process_op_conditions = self.get_process_operation_dict(process.name, auto_add=False) if process_op_conditions is not None and operation in process_op_conditions: preconditions = process_op_conditions[operation] preconditions[:] = [pre for pre in preconditions if not pre == precondition] if not preconditions: del process_op_conditions[operation] def unregister_all_process_policy_preconditions(self): """ This method removes all precondition functions registered with an operation on a process. It will not remove "hard wired" preconditions that are directly registered by processes in a container. """ for proc in self._service_op_preconditions: process_op_conditions = self.get_process_operation_dict(proc, auto_add=False) if process_op_conditions is not None: for op in process_op_conditions: preconditions = process_op_conditions[op] preconditions[:] = [pre for pre in preconditions if type(pre) == types.FunctionType] def check_process_operation_preconditions(self, process, msg, headers): """ This method is called by the ION endpoint to execute any process operation preconditions functions before allowing the operation to be called. """ operation = headers.get('op', None) if operation is None: return process_op_conditions = self.get_process_operation_dict(process.name, auto_add=False) if process_op_conditions is not None and operation in process_op_conditions: preconditions = process_op_conditions[operation] for precond in reversed(preconditions): if type(precond) in (types.MethodType, types.FunctionType): # Handle precondition which are built-in functions try: ret_val, ret_message = precond(msg, headers) except Exception as e: # TODD - Catching all exceptions and logging as errors, don't want to stop processing for this right now log.error('Executing precondition function: %s for operation: %s - %s so it will be ignored.' % (precond.__name__, operation, e.message)) ret_val = True ret_message = '' if not ret_val: raise Unauthorized(ret_message) elif isinstance(precond, basestring): try: # See if this is method within the endpoint process, if so call it method = getattr(process, precond, None) if method: ret_val, ret_message = method(msg, headers) else: # It is not a method in the process, so try to execute as a simple python function exec precond pref = locals()["precondition_func"] ret_val, ret_message = pref(process, msg, headers) except Exception as e: # TODD - Catching all exceptions and logging as errors, don't want to stop processing for this right now log.error('Executing precondition function: %s for operation: %s - %s so it will be ignored.' % (precond, operation, e.message)) ret_val = True ret_message = '' if not ret_val: raise Unauthorized(ret_message)
class GovernanceController(object): """ This is a singleton object which handles governance functionality in the container. Registers event callback for PolicyEvent to update local policies on change. """ def __init__(self, container): log.debug('GovernanceController.__init__()') self.container = container self.enabled = False self.interceptor_by_name_dict = {} self.interceptor_order = [] self.policy_decision_point_manager = None self.governance_dispatcher = None # Holds a list per service operation of policy methods to be called before operation is invoked self._service_op_preconditions = {} # Holds a list per process operation of policy methods to be called before operation is invoked self._process_op_preconditions = {} self._is_container_org_boundary = False self._container_org_name = None self._container_org_id = None # For policy debugging purposes. Keeps a list of most recent policy updates for later readout self._policy_update_log = [] self._policy_snapshot = None def start(self): log.debug("GovernanceController starting ...") self._CFG = CFG self.enabled = CFG.get_safe( 'interceptor.interceptors.governance.config.enabled', False) if not self.enabled: log.warn("GovernanceInterceptor disabled by configuration") self.policy_event_subscriber = None # Containers default to not Org Boundary and ION Root Org self._is_container_org_boundary = CFG.get_safe( 'container.org_boundary', False) self._container_org_name = CFG.get_safe( 'container.org_name', CFG.get_safe('system.root_org', 'ION')) self._container_org_id = None self._system_root_org_name = CFG.get_safe('system.root_org', 'ION') self._is_root_org_container = ( self._container_org_name == self._system_root_org_name) self.system_actor_id = None self.system_actor_user_header = None self.rr_client = ResourceRegistryServiceProcessClient( process=self.container) self.policy_client = PolicyManagementServiceProcessClient( process=self.container) if self.enabled: config = CFG.get_safe('interceptor.interceptors.governance.config') self.initialize_from_config(config) self.policy_event_subscriber = EventSubscriber( event_type=OT.PolicyEvent, callback=self.policy_event_callback) self.policy_event_subscriber.start() self._policy_snapshot = self._get_policy_snapshot() self._log_policy_update("start_governance_ctrl", message="Container start") def initialize_from_config(self, config): self.governance_dispatcher = GovernanceDispatcher() self.policy_decision_point_manager = PolicyDecisionPointManager(self) self.interceptor_order = config.get('interceptor_order', None) or [] gov_ints = config.get('governance_interceptors', None) or {} for name in gov_ints: interceptor_def = gov_ints[name] classobj = named_any(interceptor_def["class"]) classinst = classobj() self.interceptor_by_name_dict[name] = classinst def _ensure_system_actor(self): """Make sure we have a handle for the system actor""" if self.system_actor_id is None: system_actor = get_system_actor() if system_actor is not None: self.system_actor_id = system_actor._id self.system_actor_user_header = get_system_actor_header( system_actor) def stop(self): log.debug("GovernanceController stopping ...") if self.policy_event_subscriber is not None: self.policy_event_subscriber.stop() @property def is_container_org_boundary(self): return self._is_container_org_boundary @property def container_org_name(self): return self._container_org_name @property def system_root_org_name(self): return self._system_root_org_name @property def is_root_org_container(self): return self._is_root_org_container @property def CFG(self): return self._CFG @property def rr(self): """Returns the active resource registry instance if available in the container or service client. """ if self.container.has_capability('RESOURCE_REGISTRY'): return self.container.resource_registry return self.rr_client def get_container_org_boundary_id(self): """Returns the permanent org identifier configured for this container """ if not self._is_container_org_boundary: return None if self._container_org_id is None: org_ids, _ = self.rr.find_resources_ext( restype=RT.Org, attr_name="org_governance_name", attr_value=self._container_org_name, id_only=True) if org_ids: self._container_org_id = org_ids[0] return self._container_org_id # --- Interceptor management def process_incoming_message(self, invocation): """The GovernanceController hook into the incoming message interceptor stack """ self.process_message(invocation, self.interceptor_order, Invocation.PATH_IN) return self.governance_dispatcher.handle_incoming_message(invocation) def process_outgoing_message(self, invocation): """The GovernanceController hook into the outgoing message interceptor stack """ self.process_message(invocation, reversed(self.interceptor_order), Invocation.PATH_OUT) return self.governance_dispatcher.handle_outgoing_message(invocation) def process_message(self, invocation, interceptor_list, method): """ The GovernanceController hook to iterate over the interceptors to call each one and evaluate the annotations to see what actions should be done. """ for int_name in interceptor_list: interceptor_obj = self.interceptor_by_name_dict[int_name] interceptor_func = getattr(interceptor_obj, method) # Invoke interceptor function for designated path interceptor_func(invocation) # Stop processing message if an issue with the message was found by an interceptor if invocation.message_annotations.get(GovernanceDispatcher.CONVERSATION__STATUS_ANNOTATION, None) == GovernanceDispatcher.STATUS_REJECT or \ invocation.message_annotations.get(GovernanceDispatcher.POLICY__STATUS_ANNOTATION, None) == GovernanceDispatcher.STATUS_REJECT: break return invocation # --- Container policy management def policy_event_callback(self, policy_event, *args, **kwargs): """Generic policy event handler for dispatching policy related events. """ self._ensure_system_actor() log.info("Received policy event: %s", policy_event) if policy_event.type_ == OT.ResourcePolicyEvent: self.resource_policy_event_callback(policy_event, *args, **kwargs) elif policy_event.type_ == OT.RelatedResourcePolicyEvent: self.resource_policy_event_callback(policy_event, *args, **kwargs) elif policy_event.type_ == OT.ServicePolicyEvent: self.service_policy_event_callback(policy_event, *args, **kwargs) self._log_policy_update("policy_event_callback", message="Event processed", event=policy_event) def service_policy_event_callback(self, service_policy_event, *args, **kwargs): """The ServicePolicyEvent handler """ log.debug('Service policy event: %s', str(service_policy_event.__dict__)) policy_id = service_policy_event.origin service_name = service_policy_event.service_name service_op = service_policy_event.op delete_policy = True if service_policy_event.sub_type == 'DeletePolicy' else False if service_name: if self.container.proc_manager.is_local_service_process( service_name): self.update_service_access_policy(service_name, service_op, delete_policy=delete_policy) elif self.container.proc_manager.is_local_agent_process( service_name): self.update_service_access_policy(service_name, service_op, delete_policy=delete_policy) else: self.update_common_service_access_policy() def resource_policy_event_callback(self, resource_policy_event, *args, **kwargs): """The ResourcePolicyEvent handler """ log.debug('Resource policy event: %s', str(resource_policy_event.__dict__)) policy_id = resource_policy_event.origin resource_id = resource_policy_event.resource_id delete_policy = True if resource_policy_event.sub_type == 'DeletePolicy' else False self.update_resource_access_policy(resource_id, delete_policy) def reset_policy_cache(self): """Empty and reload the container's policy caches. Reload by getting policy for each of the container's processes and common policy. """ log.info('Resetting policy cache') # First remove all cached polices and operation precondition functions self._clear_container_policy_caches() # Load the common service access policies since they are shared across services self.update_common_service_access_policy() # Iterate over the processes running in the container and reload their policies proc_list = self.container.proc_manager.list_local_processes() for proc in proc_list: self.update_process_policies(proc, force_update=False) self._log_policy_update("reset_policy_cache") def _clear_container_policy_caches(self): self.policy_decision_point_manager.clear_policy_cache() self.unregister_all_process_policy_preconditions() def update_process_policies(self, process_instance, safe_mode=False, force_update=True): """ Load any applicable process policies for a container process. To be called by when spawning a new process, or when policy is reset. @param process_instance The ION process for which to load policy @param safe_mode If True, will not attempt to read policy if Policy MS not available """ # NOTE: During restart, we rely on the bootstrap code to remove registration of Policy MS if safe_mode and not self._is_policy_management_service_available(): if not is_testing() and (process_instance.name not in { "resource_registry", "system_management", "directory", "identity_management" } and process_instance._proc_name != "event_persister"): # We are in the early phases of bootstrapping log.warn( "update_process_policies(%s) - No update. Policy MS not available", process_instance._proc_name) self._log_policy_update( "update_process_policies", message="No update. Policy MS not available", process=process_instance) return self._ensure_system_actor() if process_instance._proc_type == PROCTYPE_SERVICE: self.update_service_access_policy( process_instance._proc_listen_name, force_update=force_update) elif process_instance._proc_type == PROCTYPE_AGENT: # Load any existing policies for this agent with type or name if process_instance.resource_type is None: self.update_service_access_policy(process_instance.name, force_update=force_update) else: self.update_service_access_policy( process_instance.resource_type, force_update=force_update) if process_instance.resource_id: # Load any existing policies for this resource self.update_resource_access_policy( process_instance.resource_id, force_update=force_update) self._log_policy_update("update_process_policies", message="Checked", process=process_instance) def update_common_service_access_policy(self, delete_policy=False): """Update policy common to all services""" if self.policy_decision_point_manager is None: return try: rules = self.policy_client.get_active_service_access_policy_rules( service_name='', org_name=self._container_org_name, headers=self.system_actor_user_header) self.policy_decision_point_manager.set_common_service_policy_rules( rules) except Exception as e: # If the resource does not exist, just ignore it - but log a warning. log.warn("There was an error applying access policy: %s" % e.message) def update_service_access_policy(self, service_name, service_op='', delete_policy=False, force_update=True): """Update policy for a service""" if self.policy_decision_point_manager is None: return if not force_update and not service_op and self.policy_decision_point_manager.has_service_policy( service_name): log.info("Skipping update of service %s policy - already cached", service_name) return try: if service_op: policies = self.policy_client.get_active_service_operation_preconditions( service_name=service_name, op=service_op, org_name=self._container_org_name, headers=self.system_actor_user_header) else: policies = self.policy_client.get_active_service_access_policy_rules( service_name=service_name, org_name=self._container_org_name, headers=self.system_actor_user_header) # First update any access policy rules svc_access_policy = [ p for p in policies if p.policy_type in (PolicyTypeEnum.COMMON_SERVICE_ACCESS, PolicyTypeEnum.SERVICE_ACCESS) ] self.policy_decision_point_manager.set_service_policy_rules( service_name, svc_access_policy) # Next update any precondition policies svc_preconditions = [ p for p in policies if p.policy_type == PolicyTypeEnum.SERVICE_OP_PRECOND ] # There can be several local processes for a service procs = self.container.proc_manager.get_local_service_processes( service_name) for proc in procs: if svc_preconditions: for op_pre_policy in svc_preconditions: for pre_check in op_pre_policy.preconditions: self.unregister_process_operation_precondition( proc, op_pre_policy.op, pre_check) if not delete_policy: self.register_process_operation_precondition( proc, op_pre_policy.op, pre_check) else: # Unregister all, just in case self.unregister_all_process_operation_precondition( proc, service_op) except Exception as ex: # If the resource does not exist, just ignore it - but log a warning. log.warn("Error applying access policy for service %s: %s" % (service_name, ex.message)) def update_resource_access_policy(self, resource_id, delete_policy=False, force_update=True): """Update policy for a resource (such as a device fronted by an agent process)""" if self.policy_decision_point_manager is None: return if self.policy_decision_point_manager.has_resource_policy(resource_id): return try: policy_list = self.policy_client.get_active_resource_access_policy_rules( resource_id, headers=self.system_actor_user_header) self.policy_decision_point_manager.set_resource_policy_rules( resource_id, policy_list) except Exception as e: # If the resource does not exist, just ignore it - but log a warning. log.warn( "There was an error applying access policy for resource %s: %s", resource_id, e.message) def update_process_access_policy(self, process_key, service_op='', delete_policy=False, force_update=True): pass # procs, op_preconditions = [], None # try: # # There can be several local processes for a service all with different names # procs = self.container.proc_manager.get_local_service_processes(service_name) # if procs: # op_preconditions = self.policy_client.get_active_service_operation_preconditions( # service_name=service_name, op=service_op, org_name=self._container_org_name, # headers=self.system_actor_user_header) # except Exception as ex: # # If the resource does not exist, just ignore it - but log a warning. # log.warn("Error applying precondition access policy for service %s: %s" % (service_name, ex.message)) # # for proc in procs: # try: # if op_preconditions: # for op in op_preconditions: # for pre in op.preconditions: # self.unregister_process_operation_precondition(proc, op.op, pre) # if not delete_policy: # self.register_process_operation_precondition(proc, op.op, pre) # else: # # Unregister all, just in case # self.unregister_all_process_operation_precondition(proc, service_op) # except Exception as ex: # # If the resource does not exist, just ignore it - but log a warning. # log.warn("Error applying precondition access policy for process %s of service %s: %s" % (proc, service_name, ex.message)) def get_active_policies(self): container_policies = dict() container_policies[ 'common_service_access'] = self.policy_decision_point_manager.load_common_service_pdp container_policies['service_access'] = { k: v for (k, v) in self.policy_decision_point_manager. service_policy_decision_point.iteritems() if v is not None } container_policies['resource_access'] = { k: v for (k, v) in self.policy_decision_point_manager. resource_policy_decision_point.iteritems() if v is not None } container_policies['service_operation'] = dict( self._service_op_preconditions) #log.info(container_policies) return container_policies def _is_policy_management_service_available(self): """ Method to verify if the Policy Management Service is running in the system. If the container cannot connect to the RR then assume it is remote container so do not try to access Policy Management Service """ policy_service = get_service_registry().is_service_available( 'policy_management', True) if policy_service: return True return False def _get_policy_snapshot(self): """Debugging helper that snapshot copies the current container's policy state. """ policy_snap = {} policy_snap["snap_ts"] = get_ion_ts() policies = self.get_active_policies() common_list = [] policy_snap["common_pdp"] = common_list for rule in policies.get("common_service_access", {}).policy.rules: rule_dict = dict(id=rule.id, description=rule.description, effect=rule.effect.value) common_list.append(rule_dict) service_dict = {} policy_snap["service_pdp"] = service_dict for (svc_name, sp) in policies.get("service_access", {}).iteritems(): for rule in sp.policy.rules: if svc_name not in service_dict: service_dict[svc_name] = [] rule_dict = dict(id=rule.id, description=rule.description, effect=rule.effect.value) service_dict[svc_name].append(rule_dict) service_pre_dict = {} policy_snap["service_precondition"] = service_pre_dict for (svc_name, sp) in policies.get("service_operation", {}).iteritems(): for op, f in sp.iteritems(): if svc_name not in service_pre_dict: service_pre_dict[svc_name] = [] service_pre_dict[svc_name].append(op) resource_dict = {} policy_snap["resource_pdp"] = resource_dict for (res_name, sp) in policies.get("resource_access", {}).iteritems(): for rule in sp.policy.rules: if res_name not in service_dict: resource_dict[res_name] = [] rule_dict = dict(id=rule.id, description=rule.description, effect=rule.effect.value) resource_dict[res_name].append(rule_dict) return policy_snap def _log_policy_update(self, update_type=None, message=None, event=None, process=None): policy_update_dict = {} policy_update_dict["update_ts"] = get_ion_ts() policy_update_dict["update_type"] = update_type or "" policy_update_dict["message"] = message or "" if event: policy_update_dict["event._id"] = getattr(event, "_id", "") policy_update_dict["event.ts_created"] = getattr( event, "ts_created", "") policy_update_dict["event.type_"] = getattr(event, "type_", "") policy_update_dict["event.sub_type"] = getattr( event, "sub_type", "") if process: policy_update_dict["proc._proc_name"] = getattr( process, "_proc_name", "") policy_update_dict["proc.name"] = getattr(process, "name", "") policy_update_dict["proc._proc_listen_name"] = getattr( process, "_proc_listen_name", "") policy_update_dict["proc.resource_type"] = getattr( process, "resource_type", "") policy_update_dict["proc.resource_id"] = getattr( process, "resource_id", "") any_change = False # Change can only be detected in number/names of policy not content snapshot = self._policy_snapshot policy_now = self._get_policy_snapshot() # Comparison of snapshot to current policy try: def compare_policy(pol_cur, pol_snap, key, res): pol_cur_set = { d["id"] if isinstance(d, dict) else d for d in pol_cur } pol_snap_set = { d["id"] if isinstance(d, dict) else d for d in pol_snap } if pol_cur_set != pol_snap_set: policy_update_dict["snap.%s.%s.added" % (key, res)] = pol_cur_set - pol_snap_set policy_update_dict["snap.%s.%s.removed" % (key, res)] = pol_snap_set - pol_cur_set log.debug("Policy changed for %s.%s: %s vs %s" % (key, res, pol_cur_set, pol_snap_set)) return True return False policy_update_dict["snap.snap_ts"] = snapshot["snap_ts"] for key in ("common_pdp", "service_pdp", "service_precondition", "resource_pdp"): pol_snap = snapshot[key] pol_cur = policy_now[key] if isinstance(pol_cur, dict): for res in pol_cur.keys(): pol_list = pol_cur[res] snap_list = pol_snap.get(res, []) any_change = compare_policy(pol_list, snap_list, key, res) or any_change elif isinstance(pol_cur, list): any_change = compare_policy(pol_cur, pol_snap, key, "common") or any_change policy_update_dict["snap.policy_changed"] = str(any_change) except Exception as ex: log.warn("Cannot compare current policy to prior snapshot", exc_info=True) self._policy_update_log.append(policy_update_dict) self._policy_update_log = self._policy_update_log[-100:] self._policy_snapshot = policy_now if any_change: log.debug("Container policy changed. Cause: %s/%s" % (update_type, message)) else: log.debug("Container policy checked but no change. Cause: %s/%s" % (update_type, message)) # --- Methods for managing operation specific preconditions def get_process_operation_dict(self, process_name, auto_add=True): if process_name in self._service_op_preconditions: return self._service_op_preconditions[process_name] if auto_add: self._service_op_preconditions[process_name] = dict() return self._service_op_preconditions[process_name] return None def register_process_operation_precondition(self, process, operation, precondition): """ This method is used to register process operation precondition functions with the governance controller. The endpoint code will call check_process_operation_preconditions() below before calling the business logic operation and if any of the precondition functions return False, then the request is denied as Unauthorized. At some point, this should be refactored to by another interceptor, but at the operation level. """ if not hasattr(process, operation): raise NotFound( "The operation %s does not exist for the %s process" % (operation, process.name)) if type(precondition ) == types.MethodType and precondition.im_self != process: raise NotFound("The method %s does not exist for the %s process." % (str(precondition), process.name)) process_op_conditions = self.get_process_operation_dict(process.name) if operation in process_op_conditions: process_op_conditions[operation].append(precondition) else: preconditions = list() preconditions.append(precondition) process_op_conditions[operation] = preconditions def unregister_all_process_operation_precondition(self, process, operation): """ This method removes all precondition functions registered with an operation on a process. Care should be taken with this call, as it can remove "hard wired" preconditions that are directly registered by processes in a container. """ process_op_conditions = self.get_process_operation_dict(process.name, auto_add=False) if process_op_conditions is not None and operation in process_op_conditions: del process_op_conditions[operation] def unregister_process_operation_precondition(self, process, operation, precondition): """ This method removes a specific precondition function registered with an operation on a process. Care should be taken with this call, as it can remove "hard wired" preconditions that are directly registered by processes in a container. """ #Just skip this if there operation is not passed in. if operation is None: return if not hasattr(process, operation): raise NotFound( "The operation %s does not exist for the %s service" % (operation, process.name)) process_op_conditions = self.get_process_operation_dict(process.name, auto_add=False) if process_op_conditions is not None and operation in process_op_conditions: preconditions = process_op_conditions[operation] preconditions[:] = [ pre for pre in preconditions if not pre == precondition ] if not preconditions: del process_op_conditions[operation] def unregister_all_process_policy_preconditions(self): """ This method removes all precondition functions registered with an operation on a process. It will not remove "hard wired" preconditions that are directly registered by processes in a container. """ for proc in self._service_op_preconditions: process_op_conditions = self.get_process_operation_dict( proc, auto_add=False) if process_op_conditions is not None: for op in process_op_conditions: preconditions = process_op_conditions[op] preconditions[:] = [ pre for pre in preconditions if type(pre) == types.FunctionType ] def check_process_operation_preconditions(self, process, msg, headers): """ This method is called by the ION endpoint to execute any process operation preconditions functions before allowing the operation to be called. """ operation = headers.get('op', None) if operation is None: return process_op_conditions = self.get_process_operation_dict(process.name, auto_add=False) if process_op_conditions is not None and operation in process_op_conditions: preconditions = process_op_conditions[operation] for precond in reversed(preconditions): if type(precond) in (types.MethodType, types.FunctionType): # Handle precondition which are built-in functions try: ret_val, ret_message = precond(msg, headers) except Exception as e: # TODD - Catching all exceptions and logging as errors, don't want to stop processing for this right now log.error( 'Executing precondition function: %s for operation: %s - %s so it will be ignored.' % (precond.__name__, operation, e.message)) ret_val = True ret_message = '' if not ret_val: raise Unauthorized(ret_message) elif isinstance(precond, basestring): try: # See if this is method within the endpoint process, if so call it method = getattr(process, precond, None) if method: ret_val, ret_message = method(msg, headers) else: # It is not a method in the process, so try to execute as a simple python function exec precond pref = locals()["precondition_func"] ret_val, ret_message = pref(process, msg, headers) except Exception as e: # TODD - Catching all exceptions and logging as errors, don't want to stop processing for this right now log.error( 'Executing precondition function: %s for operation: %s - %s so it will be ignored.' % (precond, operation, e.message)) ret_val = True ret_message = '' if not ret_val: raise Unauthorized(ret_message)