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

1 files changed, 23 insertions, 7 deletions

diff --git a/openstackclient/identity/v2_0/user.py b/openstackclient/identity/v2_0/user.py
index 729c6ac8..2ebcba18 100644
--- a/openstackclient/identity/v2_0/user.py
+++ b/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.