Add --or-show option to user create

The --or-show option is added to create commands for the common case
of needing to ensure an object exists and getting its properties if
it does or creating a new one if it does not exist.

Note that if the object exists, any additional options that would
set values in a newly created object are ignored if the object
exists.

FakeResource needs the __name__ attribute to fall through utils.find_resource.

Prove the concept on v2 user create then propogate once we're happy with it...

Change-Id: I6268566514840c284e6a1d44b409a81d6699ef99

openstackclient/identity/v2_0/user.py

@@ -71,6 +71,11 @@ class CreateUser(show.ShowOne):
             action='store_true',
             help=_('Disable user'),
         )
+        parser.add_argument(
+            '--or-show',
+            action='store_true',
+            help=_('Return existing user'),
+        )
         return parser
 
     def take_action(self, parsed_args):
@@ -91,13 +96,24 @@ class CreateUser(show.ShowOne):
         if parsed_args.password_prompt:
             parsed_args.password = utils.get_password(self.app.stdin)
 
-        user = identity_client.users.create(
-            parsed_args.name,
-            parsed_args.password,
-            parsed_args.email,
-            tenant_id=project_id,
-            enabled=enabled,
-        )
+        try:
+            user = identity_client.users.create(
+                parsed_args.name,
+                parsed_args.password,
+                parsed_args.email,
+                tenant_id=project_id,
+                enabled=enabled,
+            )
+        except ksc_exc.Conflict as e:
+            if parsed_args.or_show:
+                user = utils.find_resource(
+                    identity_client.users,
+                    parsed_args.name,
+                )
+                self.log.info('Returning existing user %s', user.name)
+            else:
+                raise e
+
         # NOTE(dtroyer): The users.create() method wants 'tenant_id' but
         #                the returned resource has 'tenantId'.  Sigh.
         #                We're using project_id now inside OSC so there.

openstackclient/tests/fakes.py

@@ -210,6 +210,7 @@ class FakeModule(object):
 
 class FakeResource(object):
     def __init__(self, manager, info, loaded=False):
+        self.__name__ = type(self).__name__
         self.manager = manager
         self._info = info
         self._add_details(info)

openstackclient/tests/identity/v2_0/test_user.py

@@ -16,6 +16,7 @@
 import copy
 import mock
 
+from keystoneclient.openstack.common.apiclient import exceptions as ksc_exc
 from openstackclient.identity.v2_0 import user
 from openstackclient.tests import fakes
 from openstackclient.tests.identity.v2_0 import fakes as identity_fakes
@@ -342,6 +343,84 @@ class TestUserCreate(TestUser):
         )
         self.assertEqual(data, datalist)
 
+    def test_user_create_or_show_exists(self):
+        def _raise_conflict(*args, **kwargs):
+            raise ksc_exc.Conflict(None)
+
+        # need to make this throw an exception...
+        self.users_mock.create.side_effect = _raise_conflict
+
+        self.users_mock.get.return_value = fakes.FakeResource(
+            None,
+            copy.deepcopy(identity_fakes.USER),
+            loaded=True,
+        )
+
+        arglist = [
+            '--or-show',
+            identity_fakes.user_name,
+        ]
+        verifylist = [
+            ('name', identity_fakes.user_name),
+            ('or_show', True),
+        ]
+        parsed_args = self.check_parser(self.cmd, arglist, verifylist)
+
+        # DisplayCommandBase.take_action() returns two tuples
+        columns, data = self.cmd.take_action(parsed_args)
+
+        # UserManager.create(name, password, email, tenant_id=, enabled=)
+        self.users_mock.get.assert_called_with(identity_fakes.user_name)
+
+        collist = ('email', 'enabled', 'id', 'name', 'project_id')
+        self.assertEqual(collist, columns)
+        datalist = (
+            identity_fakes.user_email,
+            True,
+            identity_fakes.user_id,
+            identity_fakes.user_name,
+            identity_fakes.project_id,
+        )
+        self.assertEqual(datalist, data)
+
+    def test_user_create_or_show_not_exists(self):
+        arglist = [
+            '--or-show',
+            identity_fakes.user_name,
+        ]
+        verifylist = [
+            ('name', identity_fakes.user_name),
+            ('or_show', True),
+        ]
+        parsed_args = self.check_parser(self.cmd, arglist, verifylist)
+
+        # DisplayCommandBase.take_action() returns two tuples
+        columns, data = self.cmd.take_action(parsed_args)
+
+        # Set expected values
+        kwargs = {
+            'enabled': True,
+            'tenant_id': None,
+        }
+        # UserManager.create(name, password, email, tenant_id=, enabled=)
+        self.users_mock.create.assert_called_with(
+            identity_fakes.user_name,
+            None,
+            None,
+            **kwargs
+        )
+
+        collist = ('email', 'enabled', 'id', 'name', 'project_id')
+        self.assertEqual(collist, columns)
+        datalist = (
+            identity_fakes.user_email,
+            True,
+            identity_fakes.user_id,
+            identity_fakes.user_name,
+            identity_fakes.project_id,
+        )
+        self.assertEqual(datalist, data)
+
 
 class TestUserDelete(TestUser):