text: #!/usr/bin/env python
  # Copyright (c) 2011 X.commerce, a business unit of eBay Inc.
  # Copyright 2010 United States Government as represented by the
  # Administrator of the National Aeronautics and Space Administration.
  # All Rights Reserved.
  #
  #    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.
  
  # Interactive shell based on Django:
  #
  # Copyright (c) 2005, the Lawrence Journal-World
  # All rights reserved.
  #
  # Redistribution and use in source and binary forms, with or without
  # modification, are permitted provided that the following conditions are met:
  #
  #     1. Redistributions of source code must retain the above copyright notice,
  #        this list of conditions and the following disclaimer.
  #
  #     2. Redistributions in binary form must reproduce the above copyright
  #        notice, this list of conditions and the following disclaimer in the
  #        documentation and/or other materials provided with the distribution.
  #
  #     3. Neither the name of Django nor the names of its contributors may be
  #        used to endorse or promote products derived from this software without
  #        specific prior written permission.
  #
  # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  
  
  """
    CLI interface for cinder management.
  """
  
  from __future__ import print_function
  
  import collections
  import logging as python_logging
  import prettytable
  import sys
  import time
  
  from oslo_config import cfg
  from oslo_db import exception as db_exc
  from oslo_db.sqlalchemy import migration
  from oslo_log import log as logging
  from oslo_utils import timeutils
  
  # Need to register global_opts
  from cinder.backup import rpcapi as backup_rpcapi
  from cinder.common import config  # noqa
  from cinder.common import constants
  from cinder import context
  from cinder import db
  from cinder.db import migration as db_migration
  from cinder.db.sqlalchemy import api as db_api
  from cinder.db.sqlalchemy import models
  from cinder import exception
  from cinder.i18n import _
  from cinder import objects
  from cinder.objects import base as ovo_base
  from cinder import rpc
  from cinder.scheduler import rpcapi as scheduler_rpcapi
  from cinder import version
  from cinder.volume import rpcapi as volume_rpcapi
  from cinder.volume import utils as vutils
  
  
  CONF = cfg.CONF
  
  RPC_VERSIONS = {
      'cinder-scheduler': scheduler_rpcapi.SchedulerAPI.RPC_API_VERSION,
      'cinder-volume': volume_rpcapi.VolumeAPI.RPC_API_VERSION,
      'cinder-backup': backup_rpcapi.BackupAPI.RPC_API_VERSION,
  }
  
  OVO_VERSION = ovo_base.OBJ_VERSIONS.get_current()
  
  
  def _get_non_shared_target_hosts(ctxt):
      hosts = []
      numvols_needing_update = 0
      rpc.init(CONF)
      rpcapi = volume_rpcapi.VolumeAPI()
  
      services = objects.ServiceList.get_all_by_topic(ctxt,
                                                      constants.VOLUME_TOPIC)
      for service in services:
          capabilities = rpcapi.get_capabilities(ctxt, service.host, True)
          if not capabilities.get('shared_targets', True):
              hosts.append(service.host)
              numvols_needing_update += db_api.model_query(
                  ctxt, models.Volume).filter_by(
                      shared_targets=True,
                      service_uuid=service.uuid).count()
      return hosts, numvols_needing_update
  
  
  def shared_targets_online_data_migration(ctxt, max_count):
      """Update existing volumes shared_targets flag based on capabilities."""
      non_shared_hosts = []
      completed = 0
  
      non_shared_hosts, total_vols_to_update = _get_non_shared_target_hosts(ctxt)
      for host in non_shared_hosts:
          # We use the api call here instead of going direct to
          # db query to take advantage of parsing out the host
          # correctly
          vrefs = db_api.volume_get_all_by_host(
              ctxt, host,
              filters={'shared_targets': True})
          if len(vrefs) > max_count:
              del vrefs[-(len(vrefs) - max_count):]
          max_count -= len(vrefs)
          for v in vrefs:
              db.volume_update(
                  ctxt, v['id'],
                  {'shared_targets': 0})
              completed += 1
      return total_vols_to_update, completed
  
  
  # Decorators for actions
  def args(*args, **kwargs):
      def _decorator(func):
          func.__dict__.setdefault('args', []).insert(0, (args, kwargs))
          return func
      return _decorator
  
  
  class ShellCommands(object):
      def bpython(self):
          """Runs a bpython shell.
  
          Falls back to Ipython/python shell if unavailable
          """
          self.run('bpython')
  
      def ipython(self):
          """Runs an Ipython shell.
  
          Falls back to Python shell if unavailable
          """
          self.run('ipython')
  
      def python(self):
          """Runs a python shell.
  
          Falls back to Python shell if unavailable
          """
          self.run('python')
  
      @args('--shell',
            metavar='<bpython|ipython|python>',
            help='Python shell')
      def run(self, shell=None):
          """Runs a Python interactive interpreter."""
          if not shell:
              shell = 'bpython'
  
          if shell == 'bpython':
              try:
                  import bpython
                  bpython.embed()
              except ImportError:
                  shell = 'ipython'
          if shell == 'ipython':
              try:
                  from IPython import embed
                  embed()
              except ImportError:
                  try:
                      # Ipython < 0.11
                      # Explicitly pass an empty list as arguments, because
                      # otherwise IPython would use sys.argv from this script.
                      import IPython
  
                      shell = IPython.Shell.IPShell(argv=[])
                      shell.mainloop()
                  except ImportError:
                      # no IPython module
                      shell = 'python'
  
          if shell == 'python':
              import code
              try:
                  # Try activating rlcompleter, because it's handy.
                  import readline
              except ImportError:
                  pass
              else:
                  # We don't have to wrap the following import in a 'try',
                  # because we already know 'readline' was imported successfully.
                  import rlcompleter    # noqa
                  readline.parse_and_bind("tab:complete")
              code.interact()
  
      @args('--path', required=True, help='Script path')
      def script(self, path):
          """Runs the script from the specified path with flags set properly."""
          exec(compile(open(path).read(), path, 'exec'), locals(), globals())
  
  
  def _db_error(caught_exception):
      print('%s' % caught_exception)
      print(_("The above error may show that the database has not "
              "been created.\nPlease create a database using "
              "'cinder-manage db sync' before running this command."))
      sys.exit(1)
  
  
  class HostCommands(object):
      """List hosts."""
  
      @args('zone', nargs='?', default=None,
            help='Availability Zone (default: %(default)s)')
      def list(self, zone=None):
          """Show a list of all physical hosts.
  
          Can be filtered by zone.
          args: [zone]
          """
          print(_("%(host)-25s\t%(zone)-15s") % {'host': 'host', 'zone': 'zone'})
          ctxt = context.get_admin_context()
          services = objects.ServiceList.get_all(ctxt)
          if zone:
              services = [s for s in services if s.availability_zone == zone]
          hosts = []
          for srv in services:
              if not [h for h in hosts if h['host'] == srv['host']]:
                  hosts.append(srv)
  
          for h in hosts:
              print(_("%(host)-25s\t%(availability_zone)-15s")
                    % {'host': h['host'],
                       'availability_zone': h['availability_zone']})
  
  
  class DbCommands(object):
      """Class for managing the database."""
  
      online_migrations = (
          # Added in Queens
          db.service_uuids_online_data_migration,
          # Added in Queens
          db.backup_service_online_migration,
          # Added in Queens
          db.volume_service_uuids_online_data_migration,
          # Added in Queens
          shared_targets_online_data_migration,
          # Added in Queens
          db.attachment_specs_online_data_migration
      )
  
      def __init__(self):
          pass
  
      @args('version', nargs='?', default=None, type=int,
            help='Database version')
      @args('--bump-versions', dest='bump_versions', default=False,
            action='store_true',
            help='Update RPC and Objects versions when doing offline upgrades, '
                 'with this we no longer need to restart the services twice '
                 'after the upgrade to prevent ServiceTooOld exceptions.')
      def sync(self, version=None, bump_versions=False):
          """Sync the database up to the most recent version."""
          if version is not None and version > db.MAX_INT:
              print(_('Version should be less than or equal to '
                      '%(max_version)d.') % {'max_version': db.MAX_INT})
              sys.exit(1)
          try:
              result = db_migration.db_sync(version)
          except db_exc.DBMigrationError as ex:
              print("Error during database migration: %s" % ex)
              sys.exit(1)
  
          try:
              if bump_versions:
                  ctxt = context.get_admin_context()
                  services = objects.ServiceList.get_all(ctxt)
                  for service in services:
                      rpc_version = RPC_VERSIONS[service.binary]
                      if (service.rpc_current_version != rpc_version or
                              service.object_current_version != OVO_VERSION):
                          service.rpc_current_version = rpc_version
                          service.object_current_version = OVO_VERSION
                          service.save()
          except Exception as ex:
              print(_('Error during service version bump: %s') % ex)
              sys.exit(2)
  
          return result
  
      def version(self):
          """Print the current database version."""
          print(migration.db_version(db_api.get_engine(),
                                     db_migration.MIGRATE_REPO_PATH,
                                     db_migration.INIT_VERSION))
  
      @args('age_in_days', type=int,
            help='Purge deleted rows older than age in days')
      def purge(self, age_in_days):
          """Purge deleted rows older than a given age from cinder tables."""
          age_in_days = int(age_in_days)
          if age_in_days < 0:
              print(_("Must supply a positive value for age"))
              sys.exit(1)
          if age_in_days >= (int(time.time()) / 86400):
              print(_("Maximum age is count of days since epoch."))
              sys.exit(1)
          ctxt = context.get_admin_context()
  
          try:
              db.purge_deleted_rows(ctxt, age_in_days)
          except db_exc.DBReferenceError:
              print(_("Purge command failed, check cinder-manage "
                      "logs for more details."))
              sys.exit(1)
  
      def _run_migration(self, ctxt, max_count):
          ran = 0
          migrations = {}
          for migration_meth in self.online_migrations:
              count = max_count - ran
              try:
                  found, done = migration_meth(ctxt, count)
              except Exception:
                  print(_("Error attempting to run %(method)s") %
                        {'method': migration_meth.__name__})
                  found = done = 0
  
              name = migration_meth.__name__
              remaining = found - done
              if found:
                  print(_('%(found)i rows matched query %(meth)s, %(done)i '
                          'migrated, %(remaining)i remaining') % {'found': found,
                                                                  'meth': name,
                                                                  'done': done,
                                                                  'remaining':
                                                                  remaining})
              migrations.setdefault(name, (0, 0, 0))
              migrations[name] = (migrations[name][0] + found,
                                  migrations[name][1] + done,
                                  migrations[name][2] + remaining)
              if max_count is not None:
                  ran += done
                  if ran >= max_count:
                      break
          return migrations
  
      @args('--max_count', metavar='<number>', dest='max_count', type=int,
            help='Maximum number of objects to consider.')
      def online_data_migrations(self, max_count=None):
          """Perform online data migrations for the release in batches."""
          ctxt = context.get_admin_context()
          if max_count is not None:
              unlimited = False
              if max_count < 1:
                  print(_('Must supply a positive value for max_number.'))
                  sys.exit(127)
          else:
              unlimited = True
              max_count = 50
              print(_('Running batches of %i until complete.') % max_count)
  
          # FIXME(jdg): So this is annoying and confusing,
          # we iterate through in batches until there are no
          # more updates, that's AWESOME!! BUT we only print
          # out a table reporting found/done AFTER the loop
          # here, so that means the response the user sees is
          # always a table of "needed 0" and "completed 0".
          # So it's an indication of "all done" but it seems like
          # some feedback as we go would be nice to have here.
          ran = None
          migration_info = {}
          while ran is None or ran != 0:
              migrations = self._run_migration(ctxt, max_count)
              migration_info.update(migrations)
              ran = sum([done for found, done, remaining in migrations.values()])
              if not unlimited:
                  break
          headers = ["{}".format(_('Migration')),
                     "{}".format(_('Total Needed')),
                     "{}".format(_('Completed')), ]
          t = prettytable.PrettyTable(headers)
          for name in sorted(migration_info.keys()):
              info = migration_info[name]
              t.add_row([name, info[0], info[1]])
          print(t)
  
          sys.exit(1 if ran else 0)
  
      @args('--enable-replication', action='store_true', default=False,
            help='Set replication status to enabled (default: %(default)s).')
      @args('--active-backend-id', default=None,
            help='Change the active backend ID (default: %(default)s).')
      @args('--backend-host', required=True,
            help='The backend host name.')
      def reset_active_backend(self, enable_replication, active_backend_id,
                               backend_host):
          """Reset the active backend for a host."""
  
          ctxt = context.get_admin_context()
  
          try:
              db.reset_active_backend(ctxt, enable_replication,
                                      active_backend_id, backend_host)
          except db_exc.DBReferenceError:
              print(_("Failed to reset active backend for host %s, "
                      "check cinder-manage logs for more details.") %
                    backend_host)
              sys.exit(1)
  
  
  class VersionCommands(object):
      """Class for exposing the codebase version."""
  
      def __init__(self):
          pass
  
      def list(self):
          print(version.version_string())
  
      def __call__(self):
          self.list()
  
  
  class VolumeCommands(object):
      """Methods for dealing with a cloud in an odd state."""
  
      @args('volume_id',
            help='Volume ID to be deleted')
      def delete(self, volume_id):
          """Delete a volume, bypassing the check that it must be available."""
          ctxt = context.get_admin_context()
          volume = objects.Volume.get_by_id(ctxt, volume_id)
          host = vutils.extract_host(volume.host) if volume.host else None
  
          if not host:
              print(_("Volume not yet assigned to host."))
              print(_("Deleting volume from database and skipping rpc."))
              volume.destroy()
              return
  
          if volume.status == 'in-use':
              print(_("Volume is in-use."))
              print(_("Detach volume from instance and then try again."))
              return
  
          rpc.init(CONF)
          rpcapi = volume_rpcapi.VolumeAPI()
          rpcapi.delete_volume(ctxt, volume)
  
      @args('--currenthost', required=True, help='Existing volume host name')
      @args('--newhost', required=True, help='New volume host name')
      def update_host(self, currenthost, newhost):
          """Modify the host name associated with a volume.
  
          Particularly to recover from cases where one has moved
          their Cinder Volume node, or modified their backend_name in a
          multi-backend config.
          """
          ctxt = context.get_admin_context()
          volumes = db.volume_get_all_by_host(ctxt,
                                              currenthost)
          for v in volumes:
              db.volume_update(ctxt, v['id'],
                               {'host': newhost})
  
  
  class ConfigCommands(object):
      """Class for exposing the flags defined by flag_file(s)."""
  
      def __init__(self):
          pass
  
      @args('param', nargs='?', default=None,
            help='Configuration parameter to display (default: %(default)s)')
      def list(self, param=None):
          """List parameters configured for cinder.
  
          Lists all parameters configured for cinder unless an optional argument
          is specified.  If the parameter is specified we only print the
          requested parameter.  If the parameter is not found an appropriate
          error is produced by .get*().
          """
          param = param and param.strip()
          if param:
              print('%s = %s' % (param, CONF.get(param)))
          else:
              for key, value in CONF.items():
                  print('%s = %s' % (key, value))
  
  
  class BackupCommands(object):
      """Methods for managing backups."""
  
      def list(self):
          """List all backups.
  
          List all backups (including ones in progress) and the host
          on which the backup operation is running.
          """
          ctxt = context.get_admin_context()
          backups = objects.BackupList.get_all(ctxt)
  
          hdr = "%-32s\t%-32s\t%-32s\t%-24s\t%-24s\t%-12s\t%-12s\t%-12s\t%-12s"
          print(hdr % (_('ID'),
                       _('User ID'),
                       _('Project ID'),
                       _('Host'),
                       _('Name'),
                       _('Container'),
                       _('Status'),
                       _('Size'),
                       _('Object Count')))
  
          res = "%-32s\t%-32s\t%-32s\t%-24s\t%-24s\t%-12s\t%-12s\t%-12d\t%-12d"
          for backup in backups:
              object_count = 0
              if backup['object_count'] is not None:
                  object_count = backup['object_count']
              print(res % (backup['id'],
                           backup['user_id'],
                           backup['project_id'],
                           backup['host'],
                           backup['display_name'],
                           backup['container'],
                           backup['status'],
                           backup['size'],
                           object_count))
  
      @args('--currenthost', required=True, help='Existing backup host name')
      @args('--newhost', required=True, help='New backup host name')
      def update_backup_host(self, currenthost, newhost):
          """Modify the host name associated with a backup.
  
          Particularly to recover from cases where one has moved
          their Cinder Backup node, and not set backup_use_same_backend.
          """
          ctxt = context.get_admin_context()
          backups = objects.BackupList.get_all_by_host(ctxt, currenthost)
          for bk in backups:
              bk.host = newhost
              bk.save()
  
  
  class BaseCommand(object):
      @staticmethod
      def _normalize_time(time_field):
          return time_field and timeutils.normalize_time(time_field)
  
      @staticmethod
      def _state_repr(is_up):
          return ':-)' if is_up else 'XXX'
  
  
  class ServiceCommands(BaseCommand):
      """Methods for managing services."""
      def list(self):
          """Show a list of all cinder services."""
          ctxt = context.get_admin_context()
          services = objects.ServiceList.get_all(ctxt)
          print_format = "%-16s %-36s %-16s %-10s %-5s %-20s %-12s %-15s %-36s"
          print(print_format % (_('Binary'),
                                _('Host'),
                                _('Zone'),
                                _('Status'),
                                _('State'),
                                _('Updated At'),
                                _('RPC Version'),
                                _('Object Version'),
                                _('Cluster')))
          for svc in services:
              art = self._state_repr(svc.is_up)
              status = 'disabled' if svc.disabled else 'enabled'
              updated_at = self._normalize_time(svc.updated_at)
              rpc_version = svc.rpc_current_version
              object_version = svc.object_current_version
              cluster = svc.cluster_name or ''
              print(print_format % (svc.binary, svc.host,
                                    svc.availability_zone, status, art,
                                    updated_at, rpc_version, object_version,
                                    cluster))
  
      @args('binary', type=str,
            help='Service to delete from the host.')
      @args('host_name', type=str,
            help='Host from which to remove the service.')
      def remove(self, binary, host_name):
          """Completely removes a service."""
          ctxt = context.get_admin_context()
          try:
              svc = objects.Service.get_by_args(ctxt, host_name, binary)
              svc.destroy()
          except exception.ServiceNotFound as e:
              print(_("Host not found. Failed to remove %(service)s"
                      " on %(host)s.") %
                    {'service': binary, 'host': host_name})
              print(u"%s" % e.args)
              return 2
          print(_("Service %(service)s on host %(host)s removed.") %
                {'service': binary, 'host': host_name})
  
  
  class ClusterCommands(BaseCommand):
      """Methods for managing clusters."""
      def list(self):
          """Show a list of all cinder services."""
          ctxt = context.get_admin_context()
          clusters = objects.ClusterList.get_all(ctxt, services_summary=True)
          print_format = "%-36s %-16s %-10s %-5s %-20s %-7s %-12s %-20s"
          print(print_format % (_('Name'),
                                _('Binary'),
                                _('Status'),
                                _('State'),
                                _('Heartbeat'),
                                _('Hosts'),
                                _('Down Hosts'),
                                _('Updated At')))
          for cluster in clusters:
              art = self._state_repr(cluster.is_up)
              status = 'disabled' if cluster.disabled else 'enabled'
              heartbeat = self._normalize_time(cluster.last_heartbeat)
              updated_at = self._normalize_time(cluster.updated_at)
              print(print_format % (cluster.name, cluster.binary, status, art,
                                    heartbeat, cluster.num_hosts,
                                    cluster.num_down_hosts, updated_at))
  
      @args('--recursive', action='store_true', default=False,
            help='Delete associated hosts.')
      @args('binary', type=str,
            help='Service to delete from the cluster.')
      @args('cluster-name', type=str, help='Cluster to delete.')
      def remove(self, recursive, binary, cluster_name):
          """Completely removes a cluster."""
          ctxt = context.get_admin_context()
          try:
              cluster = objects.Cluster.get_by_id(ctxt, None, name=cluster_name,
                                                  binary=binary,
                                                  get_services=recursive)
          except exception.ClusterNotFound:
              print(_("Couldn't remove cluster %s because it doesn't exist.") %
                    cluster_name)
              return 2
  
          if recursive:
              for service in cluster.services:
                  service.destroy()
  
          try:
              cluster.destroy()
          except exception.ClusterHasHosts:
              print(_("Couldn't remove cluster %s because it still has hosts.") %
                    cluster_name)
              return 2
  
          msg = _('Cluster %s successfully removed.') % cluster_name
          if recursive:
              msg = (_('%(msg)s And %(num)s services from the cluster were also '
                       'removed.') % {'msg': msg, 'num': len(cluster.services)})
          print(msg)
  
      @args('--full-rename', dest='partial',
            action='store_false', default=True,
            help='Do full cluster rename instead of just replacing provided '
                 'current cluster name and preserving backend and/or pool info.')
      @args('current', help='Current cluster name.')
      @args('new', help='New cluster name.')
      def rename(self, partial, current, new):
          """Rename cluster name for Volumes and Consistency Groups.
  
          Useful when you want to rename a cluster, particularly when the
          backend_name has been modified in a multi-backend config or we have
          moved from a single backend to multi-backend.
          """
          ctxt = context.get_admin_context()
  
          # Convert empty strings to None
          current = current or None
          new = new or None
  
          # Update Volumes
          num_vols = objects.VolumeList.include_in_cluster(
              ctxt, new, partial_rename=partial, cluster_name=current)
  
          # Update Consistency Groups
          num_cgs = objects.ConsistencyGroupList.include_in_cluster(
              ctxt, new, partial_rename=partial, cluster_name=current)
  
          if num_vols or num_cgs:
              msg = _('Successfully renamed %(num_vols)s volumes and '
                      '%(num_cgs)s consistency groups from cluster %(current)s '
                      'to %(new)s')
              print(msg % {'num_vols': num_vols, 'num_cgs': num_cgs, 'new': new,
                           'current': current})
          else:
              msg = _('No volumes or consistency groups exist in cluster '
                      '%(current)s.')
              print(msg % {'current': current})
              return 2
  
  
  class ConsistencyGroupCommands(object):
      """Methods for managing consistency groups."""
  
      @args('--currenthost', required=True, help='Existing CG host name')
      @args('--newhost', required=True, help='New CG host name')
      def update_cg_host(self, currenthost, newhost):
          """Modify the host name associated with a Consistency Group.
  
          Particularly to recover from cases where one has moved
          a host from single backend to multi-backend, or changed the host
          configuration option, or modified the backend_name in a multi-backend
          config.
          """
  
          ctxt = context.get_admin_context()
          groups = objects.ConsistencyGroupList.get_all(
              ctxt, {'host': currenthost})
          for gr in groups:
              gr.host = newhost
              gr.save()
  
  
  CATEGORIES = {
      'backup': BackupCommands,
      'config': ConfigCommands,
      'cluster': ClusterCommands,
      'cg': ConsistencyGroupCommands,
      'db': DbCommands,
      'host': HostCommands,
      'service': ServiceCommands,
      'shell': ShellCommands,
      'version': VersionCommands,
      'volume': VolumeCommands,
  }
  
  
  def methods_of(obj):
      """Return non-private methods from an object.
  
      Get all callable methods of an object that don't start with underscore
      :return: a list of tuples of the form (method_name, method)
      """
      result = []
      for i in dir(obj):
          if isinstance(getattr(obj, i),
                        collections.Callable) and not i.startswith('_'):
              result.append((i, getattr(obj, i)))
      return result
  
  
  def add_command_parsers(subparsers):
      for category in sorted(CATEGORIES):
          command_object = CATEGORIES[category]()
  
          parser = subparsers.add_parser(category)
          parser.set_defaults(command_object=command_object)
  
          category_subparsers = parser.add_subparsers(dest='action')
  
          for (action, action_fn) in methods_of(command_object):
              parser = category_subparsers.add_parser(action)
  
              action_kwargs = []
              for args, kwargs in getattr(action_fn, 'args', []):
                  parser.add_argument(*args, **kwargs)
  
              parser.set_defaults(action_fn=action_fn)
              parser.set_defaults(action_kwargs=action_kwargs)
  
  
  category_opt = cfg.SubCommandOpt('category',
                                   title='Command categories',
                                   handler=add_command_parsers)
  
  
  def get_arg_string(args):
      if args[0] == '-':
          # (Note)zhiteng: args starts with FLAGS.oparser.prefix_chars
          # is optional args. Notice that cfg module takes care of
          # actual ArgParser so prefix_chars is always '-'.
          if args[1] == '-':
              # This is long optional arg
              args = args[2:]
          else:
              args = args[1:]
  
      # We convert dashes to underscores so we can have cleaner optional arg
      # names
      if args:
          args = args.replace('-', '_')
  
      return args
  
  
  def fetch_func_args(func):
      fn_kwargs = {}
      for args, kwargs in getattr(func, 'args', []):
          # Argparser `dest` configuration option takes precedence for the name
          arg = kwargs.get('dest') or get_arg_string(args[0])
          fn_kwargs[arg] = getattr(CONF.category, arg)
  
      return fn_kwargs
  
  
  def main():
      objects.register_all()
      """Parse options and call the appropriate class/method."""
      CONF.register_cli_opt(category_opt)
      script_name = sys.argv[0]
      if len(sys.argv) < 2:
          print(_("\nOpenStack Cinder version: %(version)s\n") %
                {'version': version.version_string()})
          print(script_name + " category action [<args>]")
          print(_("Available categories:"))
          for category in CATEGORIES:
              print(_("\t%s") % category)
          sys.exit(2)
  
      try:
          CONF(sys.argv[1:], project='cinder',
               version=version.version_string())
          logging.setup(CONF, "cinder")
          python_logging.captureWarnings(True)
      except cfg.ConfigDirNotFoundError as details:
          print(_("Invalid directory: %s") % details)
          sys.exit(2)
      except cfg.ConfigFilesNotFoundError as e:
          cfg_files = e.config_files
          print(_("Failed to read configuration file(s): %s") % cfg_files)
          sys.exit(2)
  
      fn = CONF.category.action_fn
      fn_kwargs = fetch_func_args(fn)
      fn(**fn_kwargs)
  