Merge "Add --dry-run option to openstack stack create"

heatclient/osc/v1/stack.py

@@ -106,6 +106,12 @@ class CreateStack(show.ShowOne):
             metavar='<TAG1,TAG2...>',
             help=_('A list of tags to associate with the stack')
         )
+        parser.add_argument(
+            '--dry-run',
+            action='store_true',
+            help=_('Do not actually perform the stack create, but show what '
+                   'would be created')
+        )
         parser.add_argument(
             'name',
             metavar='<STACK_NAME>',
@@ -150,6 +156,30 @@ class CreateStack(show.ShowOne):
         if parsed_args.timeout:
             fields['timeout_mins'] = parsed_args.timeout
 
+        if parsed_args.dry_run:
+            stack = client.stacks.preview(**fields)
+
+            formatters = {
+                'description': heat_utils.text_wrap_formatter,
+                'template_description': heat_utils.text_wrap_formatter,
+                'stack_status_reason': heat_utils.text_wrap_formatter,
+                'parameters': heat_utils.json_formatter,
+                'outputs': heat_utils.json_formatter,
+                'resources': heat_utils.json_formatter,
+                'links': heat_utils.link_formatter,
+            }
+
+            columns = []
+            for key in stack.to_dict():
+                columns.append(key)
+            columns.sort()
+
+            return (
+                columns,
+                utils.get_item_properties(stack, columns,
+                                          formatters=formatters)
+            )
+
         stack = client.stacks.create(**fields)['stack']
         if parsed_args.wait:
             if not utils.wait_for_status(client.stacks.get, parsed_args.name,

heatclient/tests/unit/osc/v1/test_stack.py

@@ -53,6 +53,8 @@ class TestStackCreate(TestStack):
             return_value={'stack': {'id': '1234'}})
         self.stack_client.get = mock.MagicMock(
             return_value={'stack_status': 'create_complete'})
+        self.stack_client.preview = mock.MagicMock(
+            return_value=stacks.Stack(None, {'stack': {'id', '1234'}}))
         stack._authenticated_fetcher = mock.MagicMock()
 
     def test_stack_create_defaults(self):
@@ -137,6 +139,15 @@ class TestStackCreate(TestStack):
 
         self.assertRaises(exc.CommandError, self.cmd.take_action, parsed_args)
 
+    def test_stack_create_dry_run(self):
+        arglist = ['my_stack', '-t', self.template_path, '--dry-run']
+        parsed_args = self.check_parser(self.cmd, arglist, [])
+
+        self.cmd.take_action(parsed_args)
+
+        self.stack_client.preview.assert_called_with(**self.defaults)
+        self.stack_client.create.assert_not_called()
+
 
 class TestStackUpdate(TestStack):