CLI: Non-disruptive backup

This is the CLI change required to support non-disruptive backup
for volumes in 'in-use' status. A force flag is added to the create
backup CLI. The force flag needs to be True when backing up an
'in-use' volume. By default it is False and it is not needed when
backing up an 'available' volume.

The Cinder server side change is merged:
https://review.openstack.org/#/c/193937/

Partial-implements blueprint non-disruptive-backup

Change-Id: I53aff3973cc6365a5b1d40c21b0885c1d8166df5

cinderclient/tests/unit/v2/test_shell.py

@@ -359,6 +359,10 @@ class ShellTest(utils.TestCase):
         self.run_command('backup-create 1234 --incremental')
         self.assert_called('POST', '/backups')
 
+    def test_backup_force(self):
+        self.run_command('backup-create 1234 --force')
+        self.assert_called('POST', '/backups')
+
     def test_restore(self):
         self.run_command('backup-restore 1234')
         self.assert_called('POST', '/backups/1234/restore')

cinderclient/tests/unit/v2/test_volume_backups.py

@@ -36,6 +36,11 @@ class VolumeBackupsTest(utils.TestCase):
                           None, None, True)
         cs.assert_called('POST', '/backups')
 
+    def test_create_force(self):
+        cs.backups.create('2b695faf-b963-40c8-8464-274008fbcef4',
+                          None, None, False, True)
+        cs.assert_called('POST', '/backups')
+
     def test_get(self):
         backup_id = '76a17945-3c6f-435c-975b-b5685db10b62'
         cs.backups.get(backup_id)

cinderclient/v2/shell.py

@@ -1193,6 +1193,15 @@ def do_retype(cs, args):
            action='store_true',
            help='Incremental backup. Default=False.',
            default=False)
+@utils.arg('--force',
+           action='store_true',
+           help='Allows or disallows backup of a volume '
+           'when the volume is attached to an instance. '
+           'If set to True, backs up the volume whether '
+           'its status is "available" or "in-use". The backup '
+           'of an "in-use" volume means your data is crash '
+           'consistent. Default=False.',
+           default=False)
 @utils.service_type('volumev2')
 def do_backup_create(cs, args):
     """Creates a volume backup."""
@@ -1207,7 +1216,8 @@ def do_backup_create(cs, args):
                                args.container,
                                args.name,
                                args.description,
-                               args.incremental)
+                               args.incremental,
+                               args.force)
 
     info = {"volume_id": volume.id}
     info.update(backup._info)

cinderclient/v2/volume_backups.py

@@ -38,7 +38,7 @@ class VolumeBackupManager(base.ManagerWithFind):
 
     def create(self, volume_id, container=None,
                name=None, description=None,
-               incremental=False):
+               incremental=False, force=False):
         """Creates a volume backup.
 
         :param volume_id: The ID of the volume to backup.
@@ -46,13 +46,15 @@ class VolumeBackupManager(base.ManagerWithFind):
         :param name: The name of the backup.
         :param description: The description of the backup.
         :param incremental: Incremental backup.
+        :param force: If True, allows an in-use volume to be backed up.
         :rtype: :class:`VolumeBackup`
         """
         body = {'backup': {'volume_id': volume_id,
                            'container': container,
                            'name': name,
                            'description': description,
-                           'incremental': incremental}}
+                           'incremental': incremental,
+                           'force': force, }}
         return self._create('/backups', body, 'backup')
 
     def get(self, backup_id):