Add "os subnet show" command using SDK

Implement the openstack client subnet show command using SDK
calls.  This shows the details of a specific subnet.

Co-Authored-By: Terry Howe <terrylhowe@gmail.com>
Partially implements: blueprint neutron-client
Closes-Bug: #1542359

Change-Id: Iaf18b9e44af35ca0cd61033b468e0c60cd3b05d6

6 files changed, 133 insertions, 2 deletions

diff --git a/doc/source/command-objects/subnet.rst b/doc/source/command-objects/subnet.rst
index 70a0eedf..12b05665 100644
--- a/doc/source/command-objects/subnet.rst
+++ b/doc/source/command-objects/subnet.rst
@@ -18,3 +18,19 @@ List subnets
 .. option:: --long
 
     List additional fields in output
+
+subnet show
+-----------
+
+Show subnet details
+
+.. program:: subnet show
+.. code:: bash
+
+    os subnet show
+        <subnet>
+
+.. _subnet_show-subnet:
+.. describe:: <subnet>
+
+    Subnet to show (name or ID)
diff --git a/openstackclient/network/v2/subnet.py b/openstackclient/network/v2/subnet.py
index b948c656..7ed02a3a 100644
--- a/openstackclient/network/v2/subnet.py
+++ b/openstackclient/network/v2/subnet.py
@@ -30,6 +30,14 @@ _formatters = {
 }
 
 
+def _get_columns(item):
+    columns = item.keys()
+    if 'tenant_id' in columns:
+        columns.remove('tenant_id')
+        columns.append('project_id')
+    return tuple(sorted(columns))
+
+
 class ListSubnet(command.Lister):
     """List subnets"""
 
@@ -61,3 +69,23 @@ class ListSubnet(command.Lister):
                     s, columns,
                     formatters=_formatters,
                 ) for s in data))
+
+
+class ShowSubnet(command.ShowOne):
+    """Show subnet details"""
+
+    def get_parser(self, prog_name):
+        parser = super(ShowSubnet, self).get_parser(prog_name)
+        parser.add_argument(
+            'subnet',
+            metavar="<subnet>",
+            help="Subnet to show (name or ID)"
+        )
+        return parser
+
+    def take_action(self, parsed_args):
+        obj = self.app.client_manager.network.find_subnet(parsed_args.subnet,
+                                                          ignore_missing=False)
+        columns = _get_columns(obj)
+        data = utils.get_item_properties(obj, columns, formatters=_formatters)
+        return (columns, data)
diff --git a/openstackclient/tests/network/v2/fakes.py b/openstackclient/tests/network/v2/fakes.py
index 680e9cbf..c24410e1 100644
--- a/openstackclient/tests/network/v2/fakes.py
+++ b/openstackclient/tests/network/v2/fakes.py
@@ -550,18 +550,22 @@ class FakeSubnet(object):
             A FakeResource object faking the subnet
         """
         # Set default attributes.
+        project_id = 'project-id-' + uuid.uuid4().hex
         subnet_attrs = {
             'id': 'subnet-id-' + uuid.uuid4().hex,
             'name': 'subnet-name-' + uuid.uuid4().hex,
             'network_id': 'network-id-' + uuid.uuid4().hex,
             'cidr': '10.10.10.0/24',
-            'tenant_id': 'project-id-' + uuid.uuid4().hex,
+            'tenant_id': project_id,
             'enable_dhcp': True,
             'dns_nameservers': [],
             'allocation_pools': [],
             'host_routes': [],
             'ip_version': '4',
             'gateway_ip': '10.10.10.1',
+            'ipv6_address_mode': 'None',
+            'ipv6_ra_mode': 'None',
+            'subnetpool_id': 'None',
         }
 
         # Overwrite default attributes.
@@ -571,7 +575,8 @@ class FakeSubnet(object):
         subnet_methods = {
             'keys': ['id', 'name', 'network_id', 'cidr', 'enable_dhcp',
                      'allocation_pools', 'dns_nameservers', 'gateway_ip',
-                     'host_routes', 'ip_version', 'tenant_id']
+                     'host_routes', 'ip_version', 'tenant_id',
+                     'ipv6_address_mode', 'ipv6_ra_mode', 'subnetpool_id']
         }
 
         # Overwrite default methods.
@@ -580,6 +585,8 @@ class FakeSubnet(object):
         subnet = fakes.FakeResource(info=copy.deepcopy(subnet_attrs),
                                     methods=copy.deepcopy(subnet_methods),
                                     loaded=True)
+        # Set attributes with special mappings in OpenStack SDK.
+        subnet.project_id = subnet_attrs['tenant_id']
 
         return subnet
 
diff --git a/openstackclient/tests/network/v2/test_subnet.py b/openstackclient/tests/network/v2/test_subnet.py
index 5fca5edd..c02dc407 100644
--- a/openstackclient/tests/network/v2/test_subnet.py
+++ b/openstackclient/tests/network/v2/test_subnet.py
@@ -16,6 +16,7 @@ import mock
 from openstackclient.common import utils
 from openstackclient.network.v2 import subnet as subnet_v2
 from openstackclient.tests.network.v2 import fakes as network_fakes
+from openstackclient.tests import utils as tests_utils
 
 
 class TestSubnet(network_fakes.TestNetworkV2):
@@ -106,3 +107,76 @@ class TestListSubnet(TestSubnet):
         self.network.subnets.assert_called_with()
         self.assertEqual(self.columns_long, columns)
         self.assertEqual(self.data_long, list(data))
+
+
+class TestShowSubnet(TestSubnet):
+    # The subnets to be shown
+    _subnet = network_fakes.FakeSubnet.create_one_subnet()
+
+    columns = (
+        'allocation_pools',
+        'cidr',
+        'dns_nameservers',
+        'enable_dhcp',
+        'gateway_ip',
+        'host_routes',
+        'id',
+        'ip_version',
+        'ipv6_address_mode',
+        'ipv6_ra_mode',
+        'name',
+        'network_id',
+        'project_id',
+        'subnetpool_id',
+    )
+
+    data = (
+        subnet_v2._format_allocation_pools(_subnet.allocation_pools),
+        _subnet.cidr,
+        utils.format_list(_subnet.dns_nameservers),
+        _subnet.enable_dhcp,
+        _subnet.gateway_ip,
+        utils.format_list(_subnet.host_routes),
+        _subnet.id,
+        _subnet.ip_version,
+        _subnet.ipv6_address_mode,
+        _subnet.ipv6_ra_mode,
+        _subnet.name,
+        _subnet.network_id,
+        _subnet.tenant_id,
+        _subnet.subnetpool_id,
+    )
+
+    def setUp(self):
+        super(TestShowSubnet, self).setUp()
+
+        # Get the command object to test
+        self.cmd = subnet_v2.ShowSubnet(self.app, self.namespace)
+
+        self.network.find_subnet = mock.Mock(return_value=self._subnet)
+
+    def test_show_no_options(self):
+        arglist = []
+        verifylist = []
+
+        # Testing that a call without the required argument will fail and
+        # throw a "ParserExecption"
+        self.assertRaises(tests_utils.ParserException,
+                          self.check_parser, self.cmd, arglist, verifylist)
+
+    def test_show_all_options(self):
+        arglist = [
+            self._subnet.name,
+        ]
+        verifylist = [
+            ('subnet', self._subnet.name),
+        ]
+
+        parsed_args = self.check_parser(self.cmd, arglist, verifylist)
+        columns, data = self.cmd.take_action(parsed_args)
+
+        self.network.find_subnet.assert_called_with(self._subnet.name,
+                                                    ignore_missing=False)
+
+        self.assertEqual(self.columns, columns)
+        self.assertEqual(list(self.data), list(data))
diff --git a/releasenotes/notes/bug-1542359-181d28db21a2358a.yaml b/releasenotes/notes/bug-1542359-181d28db21a2358a.yaml
new file mode 100644
index 00000000..3aa7ad8e
--- /dev/null
+++ b/releasenotes/notes/bug-1542359-181d28db21a2358a.yaml
@@ -0,0 +1,5 @@
+---
+features:
+  - |
+    Add ``subnet show`` command.
+    [Bug `1542359 <https://bugs.launchpad.net/bugs/1542359>`_]
diff --git a/setup.cfg b/setup.cfg
index a6e27025..b535fd4c 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -341,6 +341,7 @@ openstack.network.v2 =
     security_group_delete = openstackclient.network.v2.security_group:DeleteSecurityGroup
     security_group_rule_delete = openstackclient.network.v2.security_group_rule:DeleteSecurityGroupRule
     subnet_list = openstackclient.network.v2.subnet:ListSubnet
+    subnet_show = openstackclient.network.v2.subnet:ShowSubnet
     subnet_pool_delete = openstackclient.network.v2.subnet_pool:DeleteSubnetPool
     subnet_pool_list = openstackclient.network.v2.subnet_pool:ListSubnetPool
     subnet_pool_show = openstackclient.network.v2.subnet_pool:ShowSubnetPool