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>

2 files changed, 134 insertions, 0 deletions

diff --git a/openstackclient/tests/unit/volume/v2/fakes.py b/openstackclient/tests/unit/volume/v2/fakes.py
index 481509f3..ad13f1b9 100644
--- a/openstackclient/tests/unit/volume/v2/fakes.py
+++ b/openstackclient/tests/unit/volume/v2/fakes.py
@@ -193,6 +193,65 @@ class FakeService(object):
         return services
 
 
+class FakeCapability(object):
+    """Fake capability."""
+
+    @staticmethod
+    def create_one_capability(attrs=None):
+        """Create a fake volume backend capability.
+
+        :param Dictionary attrs:
+            A dictionary with all attributes of the Capabilities.
+        :return:
+            A FakeResource object with capability name and attrs.
+        """
+        # Set default attribute
+        capability_info = {
+            "namespace": "OS::Storage::Capabilities::fake",
+            "vendor_name": "OpenStack",
+            "volume_backend_name": "lvmdriver-1",
+            "pool_name": "pool",
+            "driver_version": "2.0.0",
+            "storage_protocol": "iSCSI",
+            "display_name": "Capabilities of Cinder LVM driver",
+            "description": "Blah, blah.",
+            "visibility": "public",
+            "replication_targets": [],
+            "properties": {
+                "compression": {
+                    "title": "Compression",
+                    "description": "Enables compression.",
+                    "type": "boolean"
+                },
+                "qos": {
+                    "title": "QoS",
+                    "description": "Enables QoS.",
+                    "type": "boolean"
+                },
+                "replication": {
+                    "title": "Replication",
+                    "description": "Enables replication.",
+                    "type": "boolean"
+                },
+                "thin_provisioning": {
+                    "title": "Thin Provisioning",
+                    "description": "Sets thin provisioning.",
+                    "type": "boolean"
+                }
+            }
+        }
+
+        # Overwrite default attributes if there are some attributes set
+        capability_info.update(attrs or {})
+
+        capability = fakes.FakeResource(
+            None,
+            capability_info,
+            loaded=True)
+
+        return capability
+
+
 class FakeVolumeClient(object):
 
     def __init__(self, **kwargs):
@@ -233,6 +292,8 @@ class FakeVolumeClient(object):
         self.cgsnapshots.resource_class = fakes.FakeResource(None, {})
         self.auth_token = kwargs['token']
         self.management_url = kwargs['endpoint']
+        self.capabilities = mock.Mock()
+        self.capabilities.resource_class = fakes.FakeResource(None, {})
 
 
 class TestVolume(utils.TestCommand):
diff --git a/openstackclient/tests/unit/volume/v2/test_volume_backend.py b/openstackclient/tests/unit/volume/v2/test_volume_backend.py
new file mode 100644
index 00000000..73df6032
--- /dev/null
+++ b/openstackclient/tests/unit/volume/v2/test_volume_backend.py
@@ -0,0 +1,73 @@
+#
+#   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.
+#
+
+from openstackclient.tests.unit.volume.v2 import fakes as volume_fakes
+from openstackclient.volume.v2 import volume_backend
+
+
+class TestShowVolumeCapability(volume_fakes.TestVolume):
+    """Test backend capability functionality."""
+
+    # The capability to be listed
+    capability = volume_fakes.FakeCapability.create_one_capability()
+
+    def setUp(self):
+        super(TestShowVolumeCapability, self).setUp()
+
+        # Get a shortcut to the capability Mock
+        self.capability_mock = self.app.client_manager.volume.capabilities
+        self.capability_mock.get.return_value = self.capability
+
+        # Get the command object to test
+        self.cmd = volume_backend.ShowCapability(self.app, None)
+
+    def test_capability_show(self):
+        arglist = [
+            'fake',
+        ]
+        verifylist = [
+            ('host', 'fake'),
+        ]
+        parsed_args = self.check_parser(self.cmd, arglist, verifylist)
+
+        # In base command class Lister in cliff, abstract method take_action()
+        # returns a tuple containing the column names and an iterable
+        # containing the data to be listed.
+        columns, data = self.cmd.take_action(parsed_args)
+
+        expected_columns = [
+            'Title',
+            'Key',
+            'Type',
+            'Description',
+        ]
+
+        # confirming if all expected columns are present in the result.
+        self.assertEqual(expected_columns, columns)
+
+        capabilities = [
+            'Compression',
+            'Replication',
+            'QoS',
+            'Thin Provisioning',
+        ]
+
+        # confirming if all expected values are present in the result.
+        for cap in data:
+            self.assertTrue(cap[0] in capabilities)
+
+        # checking if proper call was made to get capabilities
+        self.capability_mock.get.assert_called_with(
+            'fake',
+        )