text: # Copyright 2012 OpenStack Foundation
  #
  # 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.
  
  """Main entry point into the Identity service."""
  
  import functools
  import operator
  import os
  import threading
  import uuid
  
  from oslo_config import cfg
  from oslo_log import log
  from pycadf import reason
  
  from keystone import assignment  # TODO(lbragstad): Decouple this dependency
  from keystone.common import cache
  from keystone.common import clean
  from keystone.common import dependency
  from keystone.common import driver_hints
  from keystone.common import manager
  from keystone.common.validation import validators
  import keystone.conf
  from keystone import exception
  from keystone.i18n import _
  from keystone.identity.mapping_backends import mapping
  from keystone import notifications
  from oslo_utils import timeutils
  
  
  CONF = keystone.conf.CONF
  
  LOG = log.getLogger(__name__)
  
  MEMOIZE = cache.get_memoization_decorator(group='identity')
  
  ID_MAPPING_REGION = cache.create_region(name='id mapping')
  MEMOIZE_ID_MAPPING = cache.get_memoization_decorator(group='identity',
                                                       region=ID_MAPPING_REGION)
  
  DOMAIN_CONF_FHEAD = 'keystone.'
  DOMAIN_CONF_FTAIL = '.conf'
  
  # The number of times we will attempt to register a domain to use the SQL
  # driver, if we find that another process is in the middle of registering or
  # releasing at the same time as us.
  REGISTRATION_ATTEMPTS = 10
  
  # Config Registration Types
  SQL_DRIVER = 'SQL'
  
  
  @dependency.requires('domain_config_api', 'resource_api')
  class DomainConfigs(dict):
      """Discover, store and provide access to domain specific configs.
  
      The setup_domain_drivers() call will be made via the wrapper from
      the first call to any driver function handled by this manager.
  
      Domain specific configurations are only supported for the identity backend
      and the individual configurations are either specified in the resource
      database or in individual domain configuration files, depending on the
      setting of the 'domain_configurations_from_database' config option.
  
      The result will be that for each domain with a specific configuration,
      this class will hold a reference to a ConfigOpts and driver object that
      the identity manager and driver can use.
  
      """
  
      configured = False
      driver = None
      _any_sql = False
      lock = threading.Lock()
  
      def _load_driver(self, domain_config):
          return manager.load_driver(Manager.driver_namespace,
                                     domain_config['cfg'].identity.driver,
                                     domain_config['cfg'])
  
      def _load_config_from_file(self, resource_api, file_list, domain_name):
  
          def _assert_no_more_than_one_sql_driver(new_config, config_file):
              """Ensure there is no more than one sql driver.
  
              Check to see if the addition of the driver in this new config
              would cause there to be more than one sql driver.
  
              """
              if (new_config['driver'].is_sql and
                      (self.driver.is_sql or self._any_sql)):
                  # The addition of this driver would cause us to have more than
                  # one sql driver, so raise an exception.
                  raise exception.MultipleSQLDriversInConfig(source=config_file)
              self._any_sql = self._any_sql or new_config['driver'].is_sql
  
          try:
              domain_ref = resource_api.get_domain_by_name(domain_name)
          except exception.DomainNotFound:
              LOG.warning(
                  ('Invalid domain name (%s) found in config file name'),
                  domain_name)
              return
  
          # Create a new entry in the domain config dict, which contains
          # a new instance of both the conf environment and driver using
          # options defined in this set of config files.  Later, when we
          # service calls via this Manager, we'll index via this domain
          # config dict to make sure we call the right driver
          domain_config = {}
          domain_config['cfg'] = cfg.ConfigOpts()
          keystone.conf.configure(conf=domain_config['cfg'])
          domain_config['cfg'](args=[], project='keystone',
                               default_config_files=file_list,
                               default_config_dirs=[])
          domain_config['driver'] = self._load_driver(domain_config)
          _assert_no_more_than_one_sql_driver(domain_config, file_list)
          self[domain_ref['id']] = domain_config
  
      def _setup_domain_drivers_from_files(self, standard_driver, resource_api):
          """Read the domain specific configuration files and load the drivers.
  
          Domain configuration files are stored in the domain config directory,
          and must be named of the form:
  
          keystone.<domain_name>.conf
  
          For each file, call the load config method where the domain_name
          will be turned into a domain_id and then:
  
          - Create a new config structure, adding in the specific additional
            options defined in this config file
          - Initialise a new instance of the required driver with this new config
  
          """
          conf_dir = CONF.identity.domain_config_dir
          if not os.path.exists(conf_dir):
              LOG.warning('Unable to locate domain config directory: %s',
                          conf_dir)
              return
  
          for r, d, f in os.walk(conf_dir):
              for fname in f:
                  if (fname.startswith(DOMAIN_CONF_FHEAD) and
                          fname.endswith(DOMAIN_CONF_FTAIL)):
                      if fname.count('.') >= 2:
                          self._load_config_from_file(
                              resource_api, [os.path.join(r, fname)],
                              fname[len(DOMAIN_CONF_FHEAD):
                                    -len(DOMAIN_CONF_FTAIL)])
                      else:
                          LOG.debug(('Ignoring file (%s) while scanning domain '
                                     'config directory'),
                                    fname)
  
      def _load_config_from_database(self, domain_id, specific_config):
  
          def _assert_no_more_than_one_sql_driver(domain_id, new_config):
              """Ensure adding driver doesn't push us over the limit of 1.
  
              The checks we make in this method need to take into account that
              we may be in a multiple process configuration and ensure that
              any race conditions are avoided.
  
              """
              if not new_config['driver'].is_sql:
                  self.domain_config_api.release_registration(domain_id)
                  return
  
              # To ensure the current domain is the only SQL driver, we attempt
              # to register our use of SQL. If we get it we know we are good,
              # if we fail to register it then we should:
              #
              # - First check if another process has registered for SQL for our
              #   domain, in which case we are fine
              # - If a different domain has it, we should check that this domain
              #   is still valid, in case, for example, domain deletion somehow
              #   failed to remove its registration (i.e. we self heal for these
              #   kinds of issues).
  
              domain_registered = 'Unknown'
              for attempt in range(REGISTRATION_ATTEMPTS):
                  if self.domain_config_api.obtain_registration(
                          domain_id, SQL_DRIVER):
                      LOG.debug('Domain %s successfully registered to use the '
                                'SQL driver.', domain_id)
                      return
  
                  # We failed to register our use, let's find out who is using it
                  try:
                      domain_registered = (
                          self.domain_config_api.read_registration(
                              SQL_DRIVER))
                  except exception.ConfigRegistrationNotFound:
                      msg = ('While attempting to register domain %(domain)s to '
                             'use the SQL driver, another process released it, '
                             'retrying (attempt %(attempt)s).')
                      LOG.debug(msg, {'domain': domain_id,
                                      'attempt': attempt + 1})
                      continue
  
                  if domain_registered == domain_id:
                      # Another process already registered it for us, so we are
                      # fine. In the race condition when another process is
                      # in the middle of deleting this domain, we know the domain
                      # is already disabled and hence telling the caller that we
                      # are registered is benign.
                      LOG.debug('While attempting to register domain %s to use '
                                'the SQL driver, found that another process had '
                                'already registered this domain. This is normal '
                                'in multi-process configurations.', domain_id)
                      return
  
                  # So we don't have it, but someone else does...let's check that
                  # this domain is still valid
                  try:
                      self.resource_api.get_domain(domain_registered)
                  except exception.DomainNotFound:
                      msg = ('While attempting to register domain %(domain)s to '
                             'use the SQL driver, found that it was already '
                             'registered to a domain that no longer exists '
                             '(%(old_domain)s). Removing this stale '
                             'registration and retrying (attempt %(attempt)s).')
                      LOG.debug(msg, {'domain': domain_id,
                                      'old_domain': domain_registered,
                                      'attempt': attempt + 1})
                      self.domain_config_api.release_registration(
                          domain_registered, type=SQL_DRIVER)
                      continue
  
                  # The domain is valid, so we really do have an attempt at more
                  # than one SQL driver.
                  details = (
                      _('Config API entity at /domains/%s/config') % domain_id)
                  raise exception.MultipleSQLDriversInConfig(source=details)
  
              # We fell out of the loop without either registering our domain or
              # being able to find who has it...either we were very very very
              # unlucky or something is awry.
              msg = _('Exceeded attempts to register domain %(domain)s to use '
                      'the SQL driver, the last domain that appears to have '
                      'had it is %(last_domain)s, giving up') % {
                          'domain': domain_id, 'last_domain': domain_registered}
              raise exception.UnexpectedError(msg)
  
          domain_config = {}
          domain_config['cfg'] = cfg.ConfigOpts()
          keystone.conf.configure(conf=domain_config['cfg'])
          domain_config['cfg'](args=[], project='keystone',
                               default_config_files=[],
                               default_config_dirs=[])
  
          # Override any options that have been passed in as specified in the
          # database.
          for group in specific_config:
              for option in specific_config[group]:
                  domain_config['cfg'].set_override(
                      option, specific_config[group][option],
                      group, enforce_type=True)
  
          domain_config['cfg_overrides'] = specific_config
          domain_config['driver'] = self._load_driver(domain_config)
          _assert_no_more_than_one_sql_driver(domain_id, domain_config)
          self[domain_id] = domain_config
  
      def _setup_domain_drivers_from_database(self, standard_driver,
                                              resource_api):
          """Read domain specific configuration from database and load drivers.
  
          Domain configurations are stored in the domain-config backend,
          so we go through each domain to find those that have a specific config
          defined, and for those that do we:
  
          - Create a new config structure, overriding any specific options
            defined in the resource backend
          - Initialise a new instance of the required driver with this new config
  
          """
          for domain in resource_api.list_domains():
              domain_config_options = (
                  self.domain_config_api.
                  get_config_with_sensitive_info(domain['id']))
              if domain_config_options:
                  self._load_config_from_database(domain['id'],
                                                  domain_config_options)
  
      def setup_domain_drivers(self, standard_driver, resource_api):
          # This is called by the api call wrapper
          self.driver = standard_driver
  
          if CONF.identity.domain_configurations_from_database:
              self._setup_domain_drivers_from_database(standard_driver,
                                                       resource_api)
          else:
              self._setup_domain_drivers_from_files(standard_driver,
                                                    resource_api)
          self.configured = True
  
      def get_domain_driver(self, domain_id):
          self.check_config_and_reload_domain_driver_if_required(domain_id)
          if domain_id in self:
              return self[domain_id]['driver']
  
      def get_domain_conf(self, domain_id):
          self.check_config_and_reload_domain_driver_if_required(domain_id)
          if domain_id in self:
              return self[domain_id]['cfg']
          else:
              return CONF
  
      def reload_domain_driver(self, domain_id):
          # Only used to support unit tests that want to set
          # new config values.  This should only be called once
          # the domains have been configured, since it relies on
          # the fact that the configuration files/database have already been
          # read.
          if self.configured:
              if domain_id in self:
                  self[domain_id]['driver'] = (
                      self._load_driver(self[domain_id]))
              else:
                  # The standard driver
                  self.driver = self.driver()
  
      def check_config_and_reload_domain_driver_if_required(self, domain_id):
          """Check for, and load, any new domain specific config for this domain.
  
          This is only supported for the database-stored domain specific
          configuration.
  
          When the domain specific drivers were set up, we stored away the
          specific config for this domain that was available at that time. So we
          now read the current version and compare. While this might seem
          somewhat inefficient, the sensitive config call is cached, so should be
          light weight. More importantly, when the cache timeout is reached, we
          will get any config that has been updated from any other keystone
          process.
  
          This cache-timeout approach works for both multi-process and
          multi-threaded keystone configurations. In multi-threaded
          configurations, even though we might remove a driver object (that
          could be in use by another thread), this won't actually be thrown away
          until all references to it have been broken. When that other
          thread is released back and is restarted with another command to
          process, next time it accesses the driver it will pickup the new one.
  
          """
          if (not CONF.identity.domain_specific_drivers_enabled or
                  not CONF.identity.domain_configurations_from_database):
              # If specific drivers are not enabled, then there is nothing to do.
              # If we are not storing the configurations in the database, then
              # we'll only re-read the domain specific config files on startup
              # of keystone.
              return
  
          latest_domain_config = (
              self.domain_config_api.
              get_config_with_sensitive_info(domain_id))
          domain_config_in_use = domain_id in self
  
          if latest_domain_config:
              if (not domain_config_in_use or
                      latest_domain_config != self[domain_id]['cfg_overrides']):
                  self._load_config_from_database(domain_id,
                                                  latest_domain_config)
          elif domain_config_in_use:
              # The domain specific config has been deleted, so should remove the
              # specific driver for this domain.
              try:
                  del self[domain_id]
              except KeyError:  # nosec
                  # Allow this error in case we are unlucky and in a
                  # multi-threaded situation, two threads happen to be running
                  # in lock step.
                  pass
          # If we fall into the else condition, this means there is no domain
          # config set, and there is none in use either, so we have nothing
          # to do.
  
  
  def domains_configured(f):
      """Wrap API calls to lazy load domain configs after init.
  
      This is required since the assignment manager needs to be initialized
      before this manager, and yet this manager's init wants to be
      able to make assignment calls (to build the domain configs).  So
      instead, we check if the domains have been initialized on entry
      to each call, and if requires load them,
  
      """
      @functools.wraps(f)
      def wrapper(self, *args, **kwargs):
          if (not self.domain_configs.configured and
                  CONF.identity.domain_specific_drivers_enabled):
              # If domain specific driver has not been configured, acquire the
              # lock and proceed with loading the driver.
              with self.domain_configs.lock:
                  # Check again just in case some other thread has already
                  # completed domain config.
                  if not self.domain_configs.configured:
                      self.domain_configs.setup_domain_drivers(
                          self.driver, self.resource_api)
          return f(self, *args, **kwargs)
      return wrapper
  
  
  def exception_translated(exception_type):
      """Wrap API calls to map to correct exception."""
      def _exception_translated(f):
          @functools.wraps(f)
          def wrapper(self, *args, **kwargs):
              try:
                  return f(self, *args, **kwargs)
              except exception.PublicIDNotFound as e:
                  if exception_type == 'user':
                      raise exception.UserNotFound(user_id=str(e))
                  elif exception_type == 'group':
                      raise exception.GroupNotFound(group_id=str(e))
                  elif exception_type == 'assertion':
                      raise AssertionError(_('Invalid user / password'))
                  else:
                      raise
          return wrapper
      return _exception_translated
  
  
  @notifications.listener
  @dependency.provider('identity_api')
  @dependency.requires('assignment_api', 'credential_api', 'id_mapping_api',
                       'resource_api', 'shadow_users_api', 'federation_api')
  class Manager(manager.Manager):
      """Default pivot point for the Identity backend.
  
      See :mod:`keystone.common.manager.Manager` for more details on how this
      dynamically calls the backend.
  
      This class also handles the support of domain specific backends, by using
      the DomainConfigs class. The setup call for DomainConfigs is called
      from with the @domains_configured wrapper in a lazy loading fashion
      to get around the fact that we can't satisfy the assignment api it needs
      from within our __init__() function since the assignment driver is not
      itself yet initialized.
  
      Each of the identity calls are pre-processed here to choose, based on
      domain, which of the drivers should be called. The non-domain-specific
      driver is still in place, and is used if there is no specific driver for
      the domain in question (or we are not using multiple domain drivers).
  
      Starting with Juno, in order to be able to obtain the domain from
      just an ID being presented as part of an API call, a public ID to domain
      and local ID mapping is maintained.  This mapping also allows for the local
      ID of drivers that do not provide simple UUIDs (such as LDAP) to be
      referenced via a public facing ID.  The mapping itself is automatically
      generated as entities are accessed via the driver.
  
      This mapping is only used when:
      - the entity is being handled by anything other than the default driver, or
      - the entity is being handled by the default LDAP driver and backward
      compatible IDs are not required.
  
      This means that in the standard case of a single SQL backend or the default
      settings of a single LDAP backend (since backward compatible IDs is set to
      True by default), no mapping is used. An alternative approach would be to
      always use the mapping table, but in the cases where we don't need it to
      make the public and local IDs the same. It is felt that not using the
      mapping by default is a more prudent way to introduce this functionality.
  
      """
  
      driver_namespace = 'keystone.identity'
  
      _USER = 'user'
      _GROUP = 'group'
  
      def __init__(self):
          super(Manager, self).__init__(CONF.identity.driver)
          self.domain_configs = DomainConfigs()
  
          self.event_callbacks = {
              notifications.ACTIONS.deleted: {
                  'domain': [self._domain_deleted],
                  'project': [self._unset_default_project],
              },
          }
  
      def _domain_deleted(self, service, resource_type, operation,
                          payload):
          domain_id = payload['resource_info']
  
          user_refs = self.list_users(domain_scope=domain_id)
          group_refs = self.list_groups(domain_scope=domain_id)
  
          for group in group_refs:
              # Cleanup any existing groups.
              try:
                  self.delete_group(group['id'])
              except exception.GroupNotFound:
                  LOG.debug(('Group %(groupid)s not found when deleting domain '
                             'contents for %(domainid)s, continuing with '
                             'cleanup.'),
                            {'groupid': group['id'], 'domainid': domain_id})
  
          # And finally, delete the users themselves
          for user in user_refs:
              try:
                  self.delete_user(user['id'])
              except exception.UserNotFound:
                  LOG.debug(('User %(userid)s not found when deleting domain '
                             'contents for %(domainid)s, continuing with '
                             'cleanup.'),
                            {'userid': user['id'], 'domainid': domain_id})
  
      def _unset_default_project(self, service, resource_type, operation,
                                 payload):
          """Callback, clears user default_project_id after project deletion.
  
          Notifications are used to unset a user's default project because
          there is no foreign key to the project. Projects can be in a non-SQL
          backend, making FKs impossible.
  
          """
          project_id = payload['resource_info']
          self.driver.unset_default_project_id(project_id)
  
      # Domain ID normalization methods
      def _set_domain_id_and_mapping(self, ref, domain_id, driver,
                                     entity_type):
          """Patch the domain_id/public_id into the resulting entity(ies).
  
          :param ref: the entity or list of entities to post process
          :param domain_id: the domain scope used for the call
          :param driver: the driver used to execute the call
          :param entity_type: whether this is a user or group
  
          :returns: post processed entity or list or entities
  
          Called to post-process the entity being returned, using a mapping
          to substitute a public facing ID as necessary. This method must
          take into account:
  
          - If the driver is not domain aware, then we must set the domain
            attribute of all entities irrespective of mapping.
          - If the driver does not support UUIDs, then we always want to provide
            a mapping, except for the special case of this being the default
            driver and backward_compatible_ids is set to True. This is to ensure
            that entity IDs do not change for an existing LDAP installation (only
            single domain/driver LDAP configurations were previously supported).
          - If the driver does support UUIDs, then we always create a mapping
            entry, but use the local UUID as the public ID.  The exception to
            this is that if we just have single driver (i.e. not using specific
            multi-domain configs), then we don't bother with the mapping at all.
  
          """
          conf = CONF.identity
  
          if not self._needs_post_processing(driver):
              # a classic case would be when running with a single SQL driver
              return ref
  
          LOG.debug('ID Mapping - Domain ID: %(domain)s, '
                    'Default Driver: %(driver)s, '
                    'Domains: %(aware)s, UUIDs: %(generate)s, '
                    'Compatible IDs: %(compat)s',
                    {'domain': domain_id,
                     'driver': (driver == self.driver),
                     'aware': driver.is_domain_aware(),
                     'generate': driver.generates_uuids(),
                     'compat': CONF.identity_mapping.backward_compatible_ids})
  
          if isinstance(ref, dict):
              return self._set_domain_id_and_mapping_for_single_ref(
                  ref, domain_id, driver, entity_type, conf)
          elif isinstance(ref, list):
              return self._set_domain_id_and_mapping_for_list(
                  ref, domain_id, driver, entity_type, conf)
          else:
              raise ValueError(_('Expected dict or list: %s') % type(ref))
  
      def _needs_post_processing(self, driver):
          """Return whether entity from driver needs domain added or mapping."""
          return (driver is not self.driver or not driver.generates_uuids() or
                  not driver.is_domain_aware())
  
      def _insert_new_public_id(self, local_entity, ref, driver):
          # Need to create a mapping. If the driver generates UUIDs
          # then pass the local UUID in as the public ID to use.
          public_id = None
          if driver.generates_uuids():
              public_id = ref['id']
          ref['id'] = self.id_mapping_api.create_id_mapping(
              local_entity, public_id)
          LOG.debug('Created new mapping to public ID: %s', ref['id'])
  
      def _set_domain_id_and_mapping_for_single_ref(self, ref, domain_id,
                                                    driver, entity_type, conf):
          LOG.debug('Local ID: %s', ref['id'])
          ref = ref.copy()
  
          self._insert_domain_id_if_needed(ref, driver, domain_id, conf)
  
          if self._is_mapping_needed(driver):
              local_entity = {'domain_id': ref['domain_id'],
                              'local_id': ref['id'],
                              'entity_type': entity_type}
              public_id = self.id_mapping_api.get_public_id(local_entity)
              if public_id:
                  ref['id'] = public_id
                  LOG.debug('Found existing mapping to public ID: %s',
                            ref['id'])
              else:
                  self._insert_new_public_id(local_entity, ref, driver)
          return ref
  
      def _set_domain_id_and_mapping_for_list(self, ref_list, domain_id, driver,
                                              entity_type, conf):
          """Set domain id and mapping for a list of refs.
  
          The method modifies refs in-place.
          """
          if not ref_list:
              return []
  
          for r in ref_list:
              self._insert_domain_id_if_needed(r, driver, domain_id, conf)
  
          if not self._is_mapping_needed(driver):
              return ref_list
  
          # build a map of refs for fast look-up
          refs_map = {}
          for r in ref_list:
              refs_map[(r['id'], entity_type, r['domain_id'])] = r
  
          # NOTE(breton): there are cases when the driver is not domain aware and
          # no domain_id was explicitely provided for list operation. domain_id
          # gets inserted into refs, but not passed into this method. Lets use
          # domain_id from one of the refs.
          if not domain_id:
              domain_id = ref_list[0]['domain_id']
  
          # fetch all mappings for the domain, lookup the user at the map built
          # at previous step and replace his id.
          domain_mappings = self.id_mapping_api.get_domain_mapping_list(
              domain_id)
          for _mapping in domain_mappings:
              idx = (_mapping.local_id, _mapping.entity_type, _mapping.domain_id)
              try:
                  ref = refs_map.pop(idx)
                  # due to python specifics, `ref` still points to an item in
                  # `ref_list`. That's why when we change it here, it gets
                  # changed in `ref_list`.
                  ref['id'] = _mapping.public_id
              except KeyError:
                  pass  # some old entry, skip it
  
          # at this point, all known refs were granted a public_id. For the refs
          # left, there are no mappings. They need to be created.
          for ref in refs_map.values():
              local_entity = {'domain_id': ref['domain_id'],
                              'local_id': ref['id'],
                              'entity_type': entity_type}
              self._insert_new_public_id(local_entity, ref, driver)
          return ref_list
  
      def _insert_domain_id_if_needed(self, ref, driver, domain_id, conf):
          """Insert the domain ID into the ref, if required.
  
          If the driver can't handle domains, then we need to insert the
          domain_id into the entity being returned.  If the domain_id is
          None that means we are running in a single backend mode, so to
          remain backwardly compatible, we put in the default domain ID.
          """
          if not driver.is_domain_aware():
              if domain_id is None:
                  domain_id = conf.default_domain_id
              ref['domain_id'] = domain_id
  
      def _is_mapping_needed(self, driver):
          """Return whether mapping is needed.
  
          There are two situations where we must use the mapping:
          - this isn't the default driver (i.e. multiple backends), or
          - we have a single backend that doesn't use UUIDs
          The exception to the above is that we must honor backward
          compatibility if this is the default driver (e.g. to support
          current LDAP)
          """
          is_not_default_driver = driver is not self.driver
          return (is_not_default_driver or (
              not driver.generates_uuids() and
              not CONF.identity_mapping.backward_compatible_ids))
  
      def _clear_domain_id_if_domain_unaware(self, driver, ref):
          """Clear domain_id details if driver is not domain aware."""
          if not driver.is_domain_aware() and 'domain_id' in ref:
              ref = ref.copy()
              ref.pop('domain_id')
          return ref
  
      def _select_identity_driver(self, domain_id):
          """Choose a backend driver for the given domain_id.
  
          :param domain_id: The domain_id for which we want to find a driver.  If
                            the domain_id is specified as None, then this means
                            we need a driver that handles multiple domains.
  
          :returns: chosen backend driver
  
          If there is a specific driver defined for this domain then choose it.
          If the domain is None, or there no specific backend for the given
          domain is found, then we chose the default driver.
  
          """
          if domain_id is None:
              driver = self.driver
          else:
              driver = (self.domain_configs.get_domain_driver(domain_id) or
                        self.driver)
  
          # If the driver is not domain aware (e.g. LDAP) then check to
          # ensure we are not mapping multiple domains onto it - the only way
          # that would happen is that the default driver is LDAP and the
          # domain is anything other than None or the default domain.
          if (not driver.is_domain_aware() and driver == self.driver and
              domain_id != CONF.identity.default_domain_id and
                  domain_id is not None):
                      LOG.warning('Found multiple domains being mapped to a '
                                  'driver that does not support that (e.g. '
                                  'LDAP) - Domain ID: %(domain)s, '
                                  'Default Driver: %(driver)s',
                                  {'domain': domain_id,
                                   'driver': (driver == self.driver)})
                      raise exception.DomainNotFound(domain_id=domain_id)
          return driver
  
      def _get_domain_driver_and_entity_id(self, public_id):
          """Look up details using the public ID.
  
          :param public_id: the ID provided in the call
  
          :returns: domain_id, which can be None to indicate that the driver
                    in question supports multiple domains
                    driver selected based on this domain
                    entity_id which will is understood by the driver.
  
          Use the mapping table to look up the domain, driver and local entity
          that is represented by the provided public ID.  Handle the situations
          where we do not use the mapping (e.g. single driver that understands
          UUIDs etc.)
  
          """
          conf = CONF.identity
          # First, since we don't know anything about the entity yet, we must
          # assume it needs mapping, so long as we are using domain specific
          # drivers.
          if conf.domain_specific_drivers_enabled:
              local_id_ref = self.id_mapping_api.get_id_mapping(public_id)
              if local_id_ref:
                  return (
                      local_id_ref['domain_id'],
                      self._select_identity_driver(local_id_ref['domain_id']),
                      local_id_ref['local_id'])
  
          # So either we are using multiple drivers but the public ID is invalid
          # (and hence was not found in the mapping table), or the public ID is
          # being handled by the default driver.  Either way, the only place left
          # to look is in that standard driver. However, we don't yet know if
          # this driver also needs mapping (e.g. LDAP in non backward
          # compatibility mode).
          driver = self.driver
          if driver.generates_uuids():
              if driver.is_domain_aware:
                  # No mapping required, and the driver can handle the domain
                  # information itself.  The classic case of this is the
                  # current SQL driver.
                  return (None, driver, public_id)
              else:
                  # Although we don't have any drivers of this type, i.e. that
                  # understand UUIDs but not domains, conceptually you could.
                  return (conf.default_domain_id, driver, public_id)
  
          # So the only place left to find the ID is in the default driver which
          # we now know doesn't generate UUIDs
          if not CONF.identity_mapping.backward_compatible_ids:
              # We are not running in backward compatibility mode, so we
              # must use a mapping.
              local_id_ref = self.id_mapping_api.get_id_mapping(public_id)
              if local_id_ref:
                  return (
                      local_id_ref['domain_id'],
                      driver,
                      local_id_ref['local_id'])
              else:
                  raise exception.PublicIDNotFound(id=public_id)
  
          # If we reach here, this means that the default driver
          # requires no mapping - but also doesn't understand domains
          # (e.g. the classic single LDAP driver situation). Hence we pass
          # back the public_ID unmodified and use the default domain (to
          # keep backwards compatibility with existing installations).
          #
          # It is still possible that the public ID is just invalid in
          # which case we leave this to the caller to check.
          return (conf.default_domain_id, driver, public_id)
  
      def _assert_user_and_group_in_same_backend(
              self, user_entity_id, user_driver, group_entity_id, group_driver):
          """Ensure that user and group IDs are backed by the same backend.
  
          Raise a CrossBackendNotAllowed exception if they are not from the same
          backend, otherwise return None.
  
          """
          if user_driver is not group_driver:
              # Determine first if either IDs don't exist by calling
              # the driver.get methods (which will raise a NotFound
              # exception).
              user_driver.get_user(user_entity_id)
              group_driver.get_group(group_entity_id)
              # If we get here, then someone is attempting to create a cross
              # backend membership, which is not allowed.
              raise exception.CrossBackendNotAllowed(group_id=group_entity_id,
                                                     user_id=user_entity_id)
  
      def _mark_domain_id_filter_satisfied(self, hints):
          if hints:
              for filter in hints.filters:
                  if (filter['name'] == 'domain_id' and
                          filter['comparator'] == 'equals'):
                      hints.filters.remove(filter)
  
      def _ensure_domain_id_in_hints(self, hints, domain_id):
          if (domain_id is not None and
                  not hints.get_exact_filter_by_name('domain_id')):
              hints.add_filter('domain_id', domain_id)
  
      def _set_list_limit_in_hints(self, hints, driver):
          """Set list limit in hints from driver.
  
          If a hints list is provided, the wrapper will insert the relevant
          limit into the hints so that the underlying driver call can try and
          honor it. If the driver does truncate the response, it will update the
          'truncated' attribute in the 'limit' entry in the hints list, which
          enables the caller of this function to know if truncation has taken
          place. If, however, the driver layer is unable to perform truncation,
          the 'limit' entry is simply left in the hints list for the caller to
          handle.
  
          A _get_list_limit() method is required to be present in the object
          class hierarchy, which returns the limit for this backend to which
          we will truncate.
  
          If a hints list is not provided in the arguments of the wrapped call
          then any limits set in the config file are ignored.  This allows
          internal use of such wrapped methods where the entire data set is
          needed as input for the calculations of some other API (e.g. get role
          assignments for a given project).
  
          This method, specific to identity manager, is used instead of more
          general response_truncated, because the limit for identity entities
          can be overridden in domain-specific config files. The driver to use
          is determined during processing of the passed parameters and
          response_truncated is designed to set the limit before any processing.
          """
          if hints is None:
              return
  
          list_limit = driver._get_list_limit()
          if list_limit:
              hints.set_limit(list_limit)
  
      # The actual driver calls - these are pre/post processed here as
      # part of the Manager layer to make sure we:
      #
      # - select the right driver for this domain
      # - clear/set domain_ids for drivers that do not support domains
      # - create any ID mapping that might be required
  
      @notifications.emit_event('authenticate')
      @domains_configured
      @exception_translated('assertion')
      def authenticate(self, request, user_id, password):
          domain_id, driver, entity_id = (
              self._get_domain_driver_and_entity_id(user_id))
          ref = driver.authenticate(entity_id, password)
          ref = self._set_domain_id_and_mapping(
              ref, domain_id, driver, mapping.EntityType.USER)
          ref = self._shadow_nonlocal_user(ref)
          self.shadow_users_api.set_last_active_at(ref['id'])
          return ref
  
      def _assert_default_project_id_is_not_domain(self, default_project_id):
          if default_project_id:
              # make sure project is not a domain
              try:
                  project_ref = self.resource_api.get_project(default_project_id)
                  if project_ref['is_domain'] is True:
                      msg = _("User's default project ID cannot be a "
                              "domain ID: %s")
                      raise exception.ValidationError(
                          message=(msg % default_project_id))
              except exception.ProjectNotFound:
                  # should be idempotent if project is not found so that it is
                  # backward compatible
                  pass
  
      @domains_configured
      @exception_translated('user')
      def create_user(self, user_ref, initiator=None):
          user = user_ref.copy()
          if 'password' in user:
              validators.validate_password(user['password'])
          user['name'] = clean.user_name(user['name'])
          user.setdefault('enabled', True)
          user['enabled'] = clean.user_enabled(user['enabled'])
          domain_id = user['domain_id']
          self.resource_api.get_domain(domain_id)
  
          self._assert_default_project_id_is_not_domain(
              user_ref.get('default_project_id'))
  
          # For creating a user, the domain is in the object itself
          domain_id = user_ref['domain_id']
          driver = self._select_identity_driver(domain_id)
          user = self._clear_domain_id_if_domain_unaware(driver, user)
          # Generate a local ID - in the future this might become a function of
          # the underlying driver so that it could conform to rules set down by
          # that particular driver type.
          user['id'] = uuid.uuid4().hex
          ref = driver.create_user(user['id'], user)
          notifications.Audit.created(self._USER, user['id'], initiator)
          return self._set_domain_id_and_mapping(
              ref, domain_id, driver, mapping.EntityType.USER)
  
      @domains_configured
      @exception_translated('user')
      @MEMOIZE
      def get_user(self, user_id):
          domain_id, driver, entity_id = (
              self._get_domain_driver_and_entity_id(user_id))
          ref = driver.get_user(entity_id)
          return self._set_domain_id_and_mapping(
              ref, domain_id, driver, mapping.EntityType.USER)
  
      def assert_user_enabled(self, user_id, user=None):
          """Assert the user and the user's domain are enabled.
  
          :raise AssertionError if the user or the user's domain is disabled.
          """
          if user is None:
              user = self.get_user(user_id)
          self.resource_api.assert_domain_enabled(user['domain_id'])
          if not user.get('enabled', True):
              raise AssertionError(_('User is disabled: %s') % user_id)
  
      @domains_configured
      @exception_translated('user')
      @MEMOIZE
      def get_user_by_name(self, user_name, domain_id):
          driver = self._select_identity_driver(domain_id)
          ref = driver.get_user_by_name(user_name, domain_id)
          return self._set_domain_id_and_mapping(
              ref, domain_id, driver, mapping.EntityType.USER)
  
      def _translate_expired_password_hints(self, hints):
          """Clean Up Expired Password Hints.
  
          Any `password_expires_at` filters on the `list_users` or
          `list_users_in_group` queries are modified so the call will
          return valid data.
  
          The filters `comparator` is changed to the operator specified in
          the call, otherwise it is assumed to be `equals`. The filters
          `value` becomes the timestamp specified. Both the operator and
          timestamp are validated, and will raise a InvalidOperatorError
          or ValidationTimeStampError exception respectively if invalid.
  
          """
          operators = {'lt': operator.lt, 'gt': operator.gt,
                       'eq': operator.eq, 'lte': operator.le,
                       'gte': operator.ge, 'neq': operator.ne}
          for filter_ in hints.filters:
              if 'password_expires_at' == filter_['name']:
                  # password_expires_at must be in the format
                  # 'lt:2016-11-06T15:32:17Z'. So we can assume the position
                  # of the ':' otherwise assign the operator to equals.
                  if ':' in filter_['value'][2:4]:
                      op, timestamp = filter_['value'].split(':', 1)
                  else:
                      op = 'eq'
                      timestamp = filter_['value']
  
                  try:
                      filter_['value'] = timeutils.parse_isotime(timestamp)
                  except ValueError:
                      raise exception.ValidationTimeStampError
  
                  try:
                      filter_['comparator'] = operators[op]
                  except KeyError:
                      raise exception.InvalidOperatorError(op)
          return hints
  
      def _handle_federated_attributes_in_hints(self, driver, hints):
          federated_attributes = ['idp_id', 'protocol_id', 'unique_id']
          for filter_ in hints.filters:
              if filter_['name'] in federated_attributes:
                  return self.shadow_users_api.get_federated_users(hints)
          return driver.list_users(hints)
  
      @domains_configured
      @exception_translated('user')
      def list_users(self, domain_scope=None, hints=None):
          driver = self._select_identity_driver(domain_scope)
          self._set_list_limit_in_hints(hints, driver)
          hints = hints or driver_hints.Hints()
          if driver.is_domain_aware():
              # Force the domain_scope into the hint to ensure that we only get
              # back domains for that scope.
              self._ensure_domain_id_in_hints(hints, domain_scope)
          else:
              # We are effectively satisfying any domain_id filter by the above
              # driver selection, so remove any such filter.
              self._mark_domain_id_filter_satisfied(hints)
          hints = self._translate_expired_password_hints(hints)
          ref_list = self._handle_federated_attributes_in_hints(driver, hints)
          return self._set_domain_id_and_mapping(
              ref_list, domain_scope, driver, mapping.EntityType.USER)
  
      def _require_matching_domain_id(self, new_ref, orig_ref):
          """Ensure the current domain ID matches the reference one, if any.
  
          Provided we want domain IDs to be immutable, check whether any
          domain_id specified in the ref dictionary matches the existing
          domain_id for this entity.
  
          :param new_ref: the dictionary of new values proposed for this entity
          :param orig_ref: the dictionary of original values proposed for this
                           entity
          :raises: :class:`keystone.exception.ValidationError`
          """
          if 'domain_id' in new_ref:
              if new_ref['domain_id'] != orig_ref['domain_id']:
                  raise exception.ValidationError(_('Cannot change Domain ID'))
  
      @domains_configured
      @exception_translated('user')
      def update_user(self, user_id, user_ref, initiator=None):
          old_user_ref = self.get_user(user_id)
          user = user_ref.copy()
          self._require_matching_domain_id(user, old_user_ref)
          if 'password' in user:
              validators.validate_password(user['password'])
          if 'name' in user:
              user['name'] = clean.user_name(user['name'])
          if 'enabled' in user:
              user['enabled'] = clean.user_enabled(user['enabled'])
          if 'id' in user:
              if user_id != user['id']:
                  raise exception.ValidationError(_('Cannot change user ID'))
              # Since any ID in the user dict is now irrelevant, remove its so as
              # the driver layer won't be confused by the fact the this is the
              # public ID not the local ID
              user.pop('id')
  
          self._assert_default_project_id_is_not_domain(
              user_ref.get('default_project_id'))
  
          domain_id, driver, entity_id = (
              self._get_domain_driver_and_entity_id(user_id))
          user = self._clear_domain_id_if_domain_unaware(driver, user)
          self.get_user.invalidate(self, old_user_ref['id'])
          self.get_user_by_name.invalidate(self, old_user_ref['name'],
                                           old_user_ref['domain_id'])
  
          ref = driver.update_user(entity_id, user)
  
          notifications.Audit.updated(self._USER, user_id, initiator)
  
          enabled_change = ((user.get('enabled') is False) and
                            user['enabled'] != old_user_ref.get('enabled'))
          if enabled_change or user.get('password') is not None:
              self.emit_invalidate_user_token_persistence(user_id)
  
          return self._set_domain_id_and_mapping(
              ref, domain_id, driver, mapping.EntityType.USER)
  
      @domains_configured
      @exception_translated('user')
      def delete_user(self, user_id, initiator=None):
          domain_id, driver, entity_id = (
              self._get_domain_driver_and_entity_id(user_id))
          # Get user details to invalidate the cache.
          user_old = self.get_user(user_id)
          driver.delete_user(entity_id)
          self.assignment_api.delete_user_assignments(user_id)
          self.get_user.invalidate(self, user_id)
          self.get_user_by_name.invalidate(self, user_old['name'],
                                           user_old['domain_id'])
          self.credential_api.delete_credentials_for_user(user_id)
          self.id_mapping_api.delete_id_mapping(user_id)
          notifications.Audit.deleted(self._USER, user_id, initiator)
  
          # Invalidate user role assignments cache region, as it may be caching
          # role assignments where the actor is the specified user
          assignment.COMPUTED_ASSIGNMENTS_REGION.invalidate()
  
      @domains_configured
      @exception_translated('group')
      def create_group(self, group_ref, initiator=None):
          group = group_ref.copy()
          group.setdefault('description', '')
          domain_id = group['domain_id']
          self.resource_api.get_domain(domain_id)
  
          # For creating a group, the domain is in the object itself
          domain_id = group_ref['domain_id']
          driver = self._select_identity_driver(domain_id)
          group = self._clear_domain_id_if_domain_unaware(driver, group)
          # Generate a local ID - in the future this might become a function of
          # the underlying driver so that it could conform to rules set down by
          # that particular driver type.
          group['id'] = uuid.uuid4().hex
          group['name'] = clean.group_name(group['name'])
          ref = driver.create_group(group['id'], group)
  
          notifications.Audit.created(self._GROUP, group['id'], initiator)
  
          return self._set_domain_id_and_mapping(
              ref, domain_id, driver, mapping.EntityType.GROUP)
  
      @domains_configured
      @exception_translated('group')
      @MEMOIZE
      def get_group(self, group_id):
          domain_id, driver, entity_id = (
              self._get_domain_driver_and_entity_id(group_id))
          ref = driver.get_group(entity_id)
          return self._set_domain_id_and_mapping(
              ref, domain_id, driver, mapping.EntityType.GROUP)
  
      @domains_configured
      @exception_translated('group')
      def get_group_by_name(self, group_name, domain_id):
          driver = self._select_identity_driver(domain_id)
          ref = driver.get_group_by_name(group_name, domain_id)
          return self._set_domain_id_and_mapping(
              ref, domain_id, driver, mapping.EntityType.GROUP)
  
      @domains_configured
      @exception_translated('group')
      def update_group(self, group_id, group, initiator=None):
          old_group_ref = self.get_group(group_id)
          self._require_matching_domain_id(group, old_group_ref)
          domain_id, driver, entity_id = (
              self._get_domain_driver_and_entity_id(group_id))
          group = self._clear_domain_id_if_domain_unaware(driver, group)
          if 'name' in group:
              group['name'] = clean.group_name(group['name'])
          ref = driver.update_group(entity_id, group)
          self.get_group.invalidate(self, group_id)
          notifications.Audit.updated(self._GROUP, group_id, initiator)
          return self._set_domain_id_and_mapping(
              ref, domain_id, driver, mapping.EntityType.GROUP)
  
      @domains_configured
      @exception_translated('group')
      def delete_group(self, group_id, initiator=None):
          domain_id, driver, entity_id = (
              self._get_domain_driver_and_entity_id(group_id))
          roles = self.assignment_api.list_role_assignments(group_id=group_id)
          user_ids = (u['id'] for u in self.list_users_in_group(group_id))
          driver.delete_group(entity_id)
          self.get_group.invalidate(self, group_id)
          self.id_mapping_api.delete_id_mapping(group_id)
          self.assignment_api.delete_group_assignments(group_id)
  
          notifications.Audit.deleted(self._GROUP, group_id, initiator)
  
          # If the group has been created and has users but has no role
          # assignment for the group then we do not need to revoke all the users
          # tokens and can just delete the group.
          if roles:
              for uid in user_ids:
                  self.emit_invalidate_user_token_persistence(uid)
  
          # Invalidate user role assignments cache region, as it may be caching
          # role assignments expanded from the specified group to its users
          assignment.COMPUTED_ASSIGNMENTS_REGION.invalidate()
  
      @domains_configured
      @exception_translated('group')
      def add_user_to_group(self, user_id, group_id, initiator=None):
          @exception_translated('user')
          def get_entity_info_for_user(public_id):
              return self._get_domain_driver_and_entity_id(public_id)
  
          _domain_id, group_driver, group_entity_id = (
              self._get_domain_driver_and_entity_id(group_id))
          # Get the same info for the user_id, taking care to map any
          # exceptions correctly
          _domain_id, user_driver, user_entity_id = (
              get_entity_info_for_user(user_id))
  
          self._assert_user_and_group_in_same_backend(
              user_entity_id, user_driver, group_entity_id, group_driver)
  
          group_driver.add_user_to_group(user_entity_id, group_entity_id)
  
          # Invalidate user role assignments cache region, as it may now need to
          # include role assignments from the specified group to its users
          assignment.COMPUTED_ASSIGNMENTS_REGION.invalidate()
          notifications.Audit.added_to(self._GROUP, group_id, self._USER,
                                       user_id, initiator)
  
      @domains_configured
      @exception_translated('group')
      def remove_user_from_group(self, user_id, group_id, initiator=None):
          @exception_translated('user')
          def get_entity_info_for_user(public_id):
              return self._get_domain_driver_and_entity_id(public_id)
  
          _domain_id, group_driver, group_entity_id = (
              self._get_domain_driver_and_entity_id(group_id))
          # Get the same info for the user_id, taking care to map any
          # exceptions correctly
          _domain_id, user_driver, user_entity_id = (
              get_entity_info_for_user(user_id))
  
          self._assert_user_and_group_in_same_backend(
              user_entity_id, user_driver, group_entity_id, group_driver)
  
          group_driver.remove_user_from_group(user_entity_id, group_entity_id)
          self.emit_invalidate_user_token_persistence(user_id)
  
          # Invalidate user role assignments cache region, as it may be caching
          # role assignments expanded from this group to this user
          assignment.COMPUTED_ASSIGNMENTS_REGION.invalidate()
          notifications.Audit.removed_from(self._GROUP, group_id, self._USER,
                                           user_id, initiator)
  
      def emit_invalidate_user_token_persistence(self, user_id):
          """Emit a notification to the callback system to revoke user tokens.
  
          This method and associated callback listener removes the need for
          making a direct call to another manager to delete and revoke tokens.
  
          :param user_id: user identifier
          :type user_id: string
          """
          notifications.Audit.internal(
              notifications.INVALIDATE_USER_TOKEN_PERSISTENCE, user_id
          )
  
      def emit_invalidate_grant_token_persistence(self, user_project):
          """Emit a notification to the callback system to revoke grant tokens.
  
          This method and associated callback listener removes the need for
          making a direct call to another manager to delete and revoke tokens.
  
          :param user_project: {'user_id': user_id, 'project_id': project_id}
          :type user_project: dict
          """
          notifications.Audit.internal(
              notifications.INVALIDATE_USER_PROJECT_TOKEN_PERSISTENCE,
              user_project
          )
  
      @domains_configured
      @exception_translated('user')
      def list_groups_for_user(self, user_id, hints=None):
          domain_id, driver, entity_id = (
              self._get_domain_driver_and_entity_id(user_id))
          self._set_list_limit_in_hints(hints, driver)
          hints = hints or driver_hints.Hints()
          if not driver.is_domain_aware():
              # We are effectively satisfying any domain_id filter by the above
              # driver selection, so remove any such filter
              self._mark_domain_id_filter_satisfied(hints)
          ref_list = driver.list_groups_for_user(entity_id, hints)
          return self._set_domain_id_and_mapping(
              ref_list, domain_id, driver, mapping.EntityType.GROUP)
  
      @domains_configured
      @exception_translated('group')
      def list_groups(self, domain_scope=None, hints=None):
          driver = self._select_identity_driver(domain_scope)
          self._set_list_limit_in_hints(hints, driver)
          hints = hints or driver_hints.Hints()
          if driver.is_domain_aware():
              # Force the domain_scope into the hint to ensure that we only get
              # back domains for that scope.
              self._ensure_domain_id_in_hints(hints, domain_scope)
          else:
              # We are effectively satisfying any domain_id filter by the above
              # driver selection, so remove any such filter.
              self._mark_domain_id_filter_satisfied(hints)
          ref_list = driver.list_groups(hints)
          return self._set_domain_id_and_mapping(
              ref_list, domain_scope, driver, mapping.EntityType.GROUP)
  
      @domains_configured
      @exception_translated('group')
      def list_users_in_group(self, group_id, hints=None):
          domain_id, driver, entity_id = (
              self._get_domain_driver_and_entity_id(group_id))
          self._set_list_limit_in_hints(hints, driver)
          hints = hints or driver_hints.Hints()
          if not driver.is_domain_aware():
              # We are effectively satisfying any domain_id filter by the above
              # driver selection, so remove any such filter
              self._mark_domain_id_filter_satisfied(hints)
          hints = self._translate_expired_password_hints(hints)
          ref_list = driver.list_users_in_group(entity_id, hints)
          return self._set_domain_id_and_mapping(
              ref_list, domain_id, driver, mapping.EntityType.USER)
  
      @domains_configured
      @exception_translated('group')
      def check_user_in_group(self, user_id, group_id):
          @exception_translated('user')
          def get_entity_info_for_user(public_id):
              return self._get_domain_driver_and_entity_id(public_id)
  
          _domain_id, group_driver, group_entity_id = (
              self._get_domain_driver_and_entity_id(group_id))
          # Get the same info for the user_id, taking care to map any
          # exceptions correctly
          _domain_id, user_driver, user_entity_id = (
              get_entity_info_for_user(user_id))
  
          self._assert_user_and_group_in_same_backend(
              user_entity_id, user_driver, group_entity_id, group_driver)
  
          return group_driver.check_user_in_group(user_entity_id,
                                                  group_entity_id)
  
      @domains_configured
      def change_password(self, request, user_id, original_password,
                          new_password, initiator=None):
  
          # authenticate() will raise an AssertionError if authentication fails
          try:
              self.authenticate(request, user_id, original_password)
          except exception.PasswordExpired:
              # If a password has expired, we want users to be able to change it
              pass
  
          domain_id, driver, entity_id = (
              self._get_domain_driver_and_entity_id(user_id))
          try:
              validators.validate_password(new_password)
              driver.change_password(entity_id, new_password)
          except exception.PasswordValidationError as ex:
              audit_reason = reason.Reason(str(ex), str(ex.code))
              notifications.Audit.updated(self._USER, user_id,
                                          initiator, reason=audit_reason)
              raise
  
          notifications.Audit.updated(self._USER, user_id, initiator)
          self.emit_invalidate_user_token_persistence(user_id)
  
      @MEMOIZE
      def _shadow_nonlocal_user(self, user):
          try:
              return self.shadow_users_api.get_user(user['id'])
          except exception.UserNotFound:
              return self.shadow_users_api.create_nonlocal_user(user)
  
      @MEMOIZE
      def shadow_federated_user(self, idp_id, protocol_id, unique_id,
                                display_name):
          """Map a federated user to a user.
  
          :param idp_id: identity provider id
          :param protocol_id: protocol id
          :param unique_id: unique id for the user within the IdP
          :param display_name: user's display name
  
          :returns: dictionary of the mapped User entity
          """
          user_dict = {}
          try:
              self.shadow_users_api.update_federated_user_display_name(
                  idp_id, protocol_id, unique_id, display_name)
              user_dict = self.shadow_users_api.get_federated_user(
                  idp_id, protocol_id, unique_id)
          except exception.UserNotFound:
              idp = self.federation_api.get_idp(idp_id)
              federated_dict = {
                  'idp_id': idp_id,
                  'protocol_id': protocol_id,
                  'unique_id': unique_id,
                  'display_name': display_name
              }
              user_dict = (
                  self.shadow_users_api.create_federated_user(idp['domain_id'],
                                                              federated_dict))
          self.shadow_users_api.set_last_active_at(user_dict['id'])
          return user_dict
  
  
  @dependency.provider('id_mapping_api')
  class MappingManager(manager.Manager):
      """Default pivot point for the ID Mapping backend."""
  
      driver_namespace = 'keystone.identity.id_mapping'
  
      def __init__(self):
          super(MappingManager, self).__init__(CONF.identity_mapping.driver)
  
      @MEMOIZE_ID_MAPPING
      def _get_public_id(self, domain_id, local_id, entity_type):
          return self.driver.get_public_id({'domain_id': domain_id,
                                            'local_id': local_id,
                                            'entity_type': entity_type})
  
      def get_public_id(self, local_entity):
          return self._get_public_id(local_entity['domain_id'],
                                     local_entity['local_id'],
                                     local_entity['entity_type'])
  
      @MEMOIZE_ID_MAPPING
      def get_id_mapping(self, public_id):
          return self.driver.get_id_mapping(public_id)
  
      def create_id_mapping(self, local_entity, public_id=None):
          public_id = self.driver.create_id_mapping(local_entity, public_id)
          if MEMOIZE_ID_MAPPING.should_cache(public_id):
              self._get_public_id.set(public_id, self,
                                      local_entity['domain_id'],
                                      local_entity['local_id'],
                                      local_entity['entity_type'])
              self.get_id_mapping.set(local_entity, self, public_id)
          return public_id
  
      def delete_id_mapping(self, public_id):
          local_entity = self.get_id_mapping.get(self, public_id)
          self.driver.delete_id_mapping(public_id)
          # Delete the key of entity from cache
          if local_entity:
              self._get_public_id.invalidate(self, local_entity['domain_id'],
                                             local_entity['local_id'],
                                             local_entity['entity_type'])
          self.get_id_mapping.invalidate(self, public_id)
  
      def purge_mappings(self, purge_filter):
          # Purge mapping is rarely used and only used by the command client,
          # it's quite complex to invalidate part of the cache based on the purge
          # filters, so here invalidate the whole cache when purging mappings.
          self.driver.purge_mappings(purge_filter)
          ID_MAPPING_REGION.invalidate()
  
  
  @dependency.provider('shadow_users_api')
  class ShadowUsersManager(manager.Manager):
      """Default pivot point for the Shadow Users backend."""
  
      driver_namespace = 'keystone.identity.shadow_users'
  
      def __init__(self):
          shadow_driver = CONF.shadow_users.driver
  
          super(ShadowUsersManager, self).__init__(shadow_driver)
  