Fix queue stats for v1.1 and above versions

Now in the cli of queue status v1, it's using queue.exists() to
check the existance. However, the queue.exists isn't supported
in v1.1 and above. But the queue stats should be support for
all the versions. As a result, user will see errors like
'Unavailable on versions >= 1.1'. This patches fixes it.

Closes-Bug: #1534427

Change-Id: Iaf738af4eca2419c6eba0a410b1f7e45c9720f54

zaqarclient/queues/v1/cli.py

@@ -20,6 +20,7 @@ from cliff import lister
 from cliff import show
 
 from openstackclient.common import utils
+from zaqarclient.transport import errors
 
 
 def _get_client(obj, parsed_args):
@@ -202,11 +203,13 @@ class GetQueueStats(show.ShowOne):
         queue_name = parsed_args.queue_name
         queue = client.queue(queue_name, auto_create=False)
 
-        if not queue.exists():
+        try:
+            stats = queue.stats
+        except errors.ResourceNotFound:
             raise RuntimeError('Queue(%s) does not exist.' % queue_name)
 
         columns = ("Stats",)
-        data = dict(stats=queue.stats)
+        data = dict(stats=stats)
         return columns, utils.get_dict_properties(data, columns)