Add "--remote-source" option to "volume snapshot create" command

Add "--remote-source" option to "volume snapshot create" command
to support creating snapshot from an existing remote snapshot in
volume v2 (v2 only), also add the doc, unit tests and release note.

Change-Id: I9e5fad4f0db5b44d528eb6b930edbc816e392c3a
Implements: bp cinder-command-support
Closes-Bug: #1618676
Co-Authored-By: Sheel Rana <ranasheel2000@gmail.com>

4 files changed, 74 insertions, 7 deletions

diff --git a/doc/source/command-objects/volume-snapshot.rst b/doc/source/command-objects/volume-snapshot.rst
index 141e9f78..17449035 100644
--- a/doc/source/command-objects/volume-snapshot.rst
+++ b/doc/source/command-objects/volume-snapshot.rst
@@ -17,6 +17,7 @@ Create new volume snapshot
         [--description <description>]
         [--force]
         [--property <key=value> [...] ]
+        [--remote-source <key=value> [...]]
         <snapshot-name>
 
 .. option:: --volume <volume>
@@ -37,6 +38,14 @@ Create new volume snapshot
 
     *Volume version 2 only*
 
+.. option:: --remote-source <key=value>
+
+    The attribute(s) of the exsiting remote volume snapshot
+    (admin required) (repeat option to specify multiple attributes)
+    e.g.: '--remote-source source-name=test_name --remote-source source-id=test_id'
+
+    *Volume version 2 only*
+
 .. _volume_snapshot_create-snapshot-name:
 .. describe:: <snapshot-name>
 
diff --git a/openstackclient/tests/unit/volume/v2/test_snapshot.py b/openstackclient/tests/unit/volume/v2/test_snapshot.py
index cedf21a9..8ce356ae 100644
--- a/openstackclient/tests/unit/volume/v2/test_snapshot.py
+++ b/openstackclient/tests/unit/volume/v2/test_snapshot.py
@@ -67,6 +67,7 @@ class TestSnapshotCreate(TestSnapshot):
 
         self.volumes_mock.get.return_value = self.volume
         self.snapshots_mock.create.return_value = self.new_snapshot
+        self.snapshots_mock.manage.return_value = self.new_snapshot
         # Get the command object to test
         self.cmd = volume_snapshot.CreateVolumeSnapshot(self.app, None)
 
@@ -152,6 +153,33 @@ class TestSnapshotCreate(TestSnapshot):
         self.assertEqual(self.columns, columns)
         self.assertEqual(self.data, data)
 
+    def test_snapshot_create_without_remote_source(self):
+        arglist = [
+            '--remote-source', 'source-name=test_source_name',
+            '--remote-source', 'source-id=test_source_id',
+            '--volume', self.new_snapshot.volume_id,
+        ]
+        ref_dict = {'source-name': 'test_source_name',
+                    'source-id': 'test_source_id'}
+        verifylist = [
+            ('remote_source', ref_dict),
+            ('volume', self.new_snapshot.volume_id),
+        ]
+        parsed_args = self.check_parser(self.cmd, arglist, verifylist)
+
+        columns, data = self.cmd.take_action(parsed_args)
+
+        self.snapshots_mock.manage.assert_called_with(
+            volume_id=self.new_snapshot.volume_id,
+            ref=ref_dict,
+            name=None,
+            description=None,
+            metadata=None,
+        )
+        self.snapshots_mock.create.assert_not_called()
+        self.assertEqual(self.columns, columns)
+        self.assertEqual(self.data, data)
+
 
 class TestSnapshotDelete(TestSnapshot):
 
diff --git a/openstackclient/volume/v2/volume_snapshot.py b/openstackclient/volume/v2/volume_snapshot.py
index d95a49a4..34b8fb82 100644
--- a/openstackclient/volume/v2/volume_snapshot.py
+++ b/openstackclient/volume/v2/volume_snapshot.py
@@ -65,6 +65,15 @@ class CreateVolumeSnapshot(command.ShowOne):
             help=_("Set a property to this snapshot "
                    "(repeat option to set multiple properties)"),
         )
+        parser.add_argument(
+            "--remote-source",
+            metavar="<key=value>",
+            action=parseractions.KeyValueAction,
+            help=_("The attribute(s) of the exsiting remote volume snapshot "
+                   "(admin required) (repeat option to specify multiple "
+                   "attributes) e.g.: '--remote-source source-name=test_name "
+                   "--remote-source source-id=test_id'"),
+        )
         return parser
 
     def take_action(self, parsed_args):
@@ -74,13 +83,29 @@ class CreateVolumeSnapshot(command.ShowOne):
             volume = parsed_args.snapshot_name
         volume_id = utils.find_resource(
             volume_client.volumes, volume).id
-        snapshot = volume_client.volume_snapshots.create(
-            volume_id,
-            force=parsed_args.force,
-            name=parsed_args.snapshot_name,
-            description=parsed_args.description,
-            metadata=parsed_args.property,
-        )
+        if parsed_args.remote_source:
+            # Create a new snapshot from an existing remote snapshot source
+            if parsed_args.force:
+                msg = (_("'--force' option will not work when you create "
+                         "new volume snapshot from an existing remote "
+                         "volume snapshot"))
+                LOG.warning(msg)
+            snapshot = volume_client.volume_snapshots.manage(
+                volume_id=volume_id,
+                ref=parsed_args.remote_source,
+                name=parsed_args.snapshot_name,
+                description=parsed_args.description,
+                metadata=parsed_args.property,
+            )
+        else:
+            # create a new snapshot from scratch
+            snapshot = volume_client.volume_snapshots.create(
+                volume_id,
+                force=parsed_args.force,
+                name=parsed_args.snapshot_name,
+                description=parsed_args.description,
+                metadata=parsed_args.property,
+            )
         snapshot._info.update(
             {'properties': utils.format_dict(snapshot._info.pop('metadata'))}
         )
diff --git a/releasenotes/notes/bug-1618676-04ff0f335b670567.yaml b/releasenotes/notes/bug-1618676-04ff0f335b670567.yaml
new file mode 100644
index 00000000..69282252
--- /dev/null
+++ b/releasenotes/notes/bug-1618676-04ff0f335b670567.yaml
@@ -0,0 +1,5 @@
+---
+features:
+  - Add ``--remote-source`` option to ``volume snapshot create`` command to support
+    creating volume snapshot from an existing remote volume snapshot in volume v2.
+    [Bug `1618676 <https://bugs.launchpad.net/python-openstackclient/+bug/1618676>`_]