Add volume backend capability show command

Adds and equivalend for "cinder get-capabilities" command to show the
capabilities supported by a Cinder backend.

Story: 1655624
Task: 26947

Change-Id: I38686a26cd503e45ce0102705a6632994ef10274
Signed-off-by: Sean McGinnis <sean.mcginnis@gmail.com>

1 files changed, 61 insertions, 0 deletions

diff --git a/openstackclient/volume/v2/volume_backend.py b/openstackclient/volume/v2/volume_backend.py
new file mode 100644
index 00000000..0dff18c9
--- /dev/null
+++ b/openstackclient/volume/v2/volume_backend.py
@@ -0,0 +1,61 @@
+#
+#   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.
+#
+
+"""Capability action implementations"""
+
+from osc_lib.command import command
+from osc_lib import utils
+
+from openstackclient.i18n import _
+
+
+class ShowCapability(command.Lister):
+    _description = _("Show capability command")
+
+    def get_parser(self, prog_name):
+        parser = super(ShowCapability, self).get_parser(prog_name)
+        parser.add_argument(
+            "host",
+            metavar="<host>",
+            help=_("List capabilities of specified host (host@backend-name)")
+        )
+        return parser
+
+    def take_action(self, parsed_args):
+        volume_client = self.app.client_manager.volume
+
+        columns = [
+            'Title',
+            'Key',
+            'Type',
+            'Description',
+        ]
+
+        data = volume_client.capabilities.get(parsed_args.host)
+
+        # The get capabilities API is... interesting. We only want the names of
+        # the capabilities that can set for a backend through extra specs, so
+        # we need to extract out that part of the mess that is returned.
+        print_data = []
+        keys = data.properties
+        for key in keys:
+            # Stuff the key into the details to make it easier to output
+            capability_data = data.properties[key]
+            capability_data['key'] = key
+            print_data.append(capability_data)
+
+        return (columns,
+                (utils.get_dict_properties(
+                    s, columns,
+                ) for s in print_data))