List required arguments in '--help' message in Ironic Client.

The aim of this patch is to improve commands 'ironic help node-create'
and 'ironic help port-create' so that the required arguments are
listed in a dedicated section, but not in section 'optional arguments'.

Change-Id: I73e0179170b3bb446bd9b14b095eac8ce8b5924b
Closes-Bug: #1518959

ironicclient/common/utils.py

@@ -58,8 +58,13 @@ def define_command(subparsers, command, callback, cmd_mapper):
     subparser.add_argument('-h', '--help', action='help',
                            help=argparse.SUPPRESS)
     cmd_mapper[command] = subparser
+    required_args = subparser.add_argument_group(_("Required arguments"))
+
     for (args, kwargs) in arguments:
-        subparser.add_argument(*args, **kwargs)
+        if kwargs.get('required'):
+            required_args.add_argument(*args, **kwargs)
+        else:
+            subparser.add_argument(*args, **kwargs)
     subparser.set_defaults(func=callback)
 
 

ironicclient/tests/unit/test_shell.py

@@ -106,7 +106,7 @@ class ShellTest(utils.BaseTestCase):
 
     def test_help_on_subcommand(self):
         required = [
-            '.*?^usage: ironic chassis-show',
+            ".*?^usage: ironic chassis-show",
             ".*?^Show detailed information about a chassis",
         ]
         argstrings = [
@@ -118,6 +118,36 @@ class ShellTest(utils.BaseTestCase):
                 self.assertThat(help_text,
                                 matchers.MatchesRegex(r, self.re_options))
 
+    def test_required_args_on_node_create_help(self):
+        required = [
+            ".*?^usage: ironic node-create",
+            ".*?^Register a new node with the Ironic service",
+            ".*?^Required arguments:",
+        ]
+        argstrings = [
+            'help node-create',
+        ]
+        for argstr in argstrings:
+            help_text = self.shell(argstr)
+            for r in required:
+                self.assertThat(help_text,
+                                matchers.MatchesRegex(r, self.re_options))
+
+    def test_required_args_on_port_create_help(self):
+        required = [
+            ".*?^usage: ironic port-create",
+            ".*?^Create a new port",
+            ".*?^Required arguments:",
+        ]
+        argstrings = [
+            'help port-create',
+        ]
+        for argstr in argstrings:
+            help_text = self.shell(argstr)
+            for r in required:
+                self.assertThat(help_text,
+                                matchers.MatchesRegex(r, self.re_options))
+
     def test_auth_param(self):
         self.make_env(exclude='OS_USERNAME')
         self.test_help()

ironicclient/v1/node_shell.py

@@ -207,7 +207,7 @@ def do_node_list(cc, args):
     '-d', '--driver',
     metavar='<driver>',
     required=True,
-    help='Driver used to control the node [REQUIRED].')
+    help='Driver used to control the node.')
 @cliutils.arg(
     '-i', '--driver-info',
     metavar='<key=value>',

releasenotes/notes/show-required-arguments-in-help-commands-of-node-create-port-create-b213bb28bcc94743.yaml

@@ -0,0 +1,6 @@
+fixes:
+  - |
+      Starting with this release the output of
+      commands ``ironic help node-create`` and
+      ``ironic help port-create`` will show which
+      arguments are required