Allow zun exec to take arbitrary number of arguments

The patch supports the command and arguments
in a different string. For example:
zun exec mycontainer echo hello world

Change-Id: I403dc744f434e9b09ab5e4f4314e9c1e8fd22913
Closes-Bug: #1651013

zunclient/osc/v1/containers.py

@@ -10,6 +10,7 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
+import argparse
 import logging
 
 from osc_lib.command import command
@@ -337,13 +338,14 @@ class ExecContainer(command.Command):
         parser.add_argument(
             'command',
             metavar='<command>',
+            nargs=argparse.REMAINDER,
             help='The command to execute.')
         return parser
 
     def take_action(self, parsed_args):
         client = _get_client(self, parsed_args)
         container = parsed_args.container
-        command = getattr(parsed_args, 'command')
+        command = ' '.join(parsed_args.command)
         output = client.containers.execute(container, command)
         print(output)
 

zunclient/v1/containers_shell.py

@@ -12,6 +12,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+import argparse
 import json
 
 from zunclient.common import cliutils as utils
@@ -292,10 +293,11 @@ def do_logs(cs, args):
            help='ID or name of the container to execute command in.')
 @utils.arg('command',
            metavar='<command>',
+           nargs=argparse.REMAINDER,
            help='The command to execute in a container')
 def do_exec(cs, args):
     """Execute command in a container."""
-    output = cs.containers.execute(args.container, args.command)
+    output = cs.containers.execute(args.container, ' '.join(args.command))
     print(output)