Add KeyValueAppendAction to osc-lib

This is required to support things like the '--hint' option for
'openstack server create', which allows you to specify arguments
multiple times.

Change-Id: If73cab759fa09bddf1ff519923c5972c3b2052b1
Signed-off-by: Stephen Finucane <stephenfin@redhat.com>

osc_lib/cli/parseractions.py

@@ -23,7 +23,7 @@ from osc_lib.i18n import _
 class KeyValueAction(argparse.Action):
     """A custom action to parse arguments as key=value pairs
 
-    Ensures that ``dest`` is a dict
+    Ensures that ``dest`` is a dict and values are strings.
     """
 
     def __call__(self, parser, namespace, values, option_string=None):
@@ -45,6 +45,35 @@ class KeyValueAction(argparse.Action):
             raise argparse.ArgumentTypeError(msg % str(values))
 
 
+class KeyValueAppendAction(argparse.Action):
+    """A custom action to parse arguments as key=value pairs
+
+    Ensures that ``dest`` is a dict and values are lists of strings.
+    """
+
+    def __call__(self, parser, namespace, values, option_string=None):
+        # Make sure we have an empty dict rather than None
+        if getattr(namespace, self.dest, None) is None:
+            setattr(namespace, self.dest, {})
+
+        # Add value if an assignment else remove it
+        if '=' in values:
+            key, value = values.split('=', 1)
+            # NOTE(qtang): Prevent null key setting in property
+            if '' == key:
+                msg = _("Property key must be specified: %s")
+                raise argparse.ArgumentTypeError(msg % str(values))
+
+            dest = getattr(namespace, self.dest)
+            if key in dest:
+                dest[key].append(value)
+            else:
+                dest[key] = [value]
+        else:
+            msg = _("Expected 'key=value' type, but got: %s")
+            raise argparse.ArgumentTypeError(msg % str(values))
+
+
 class MultiKeyValueAction(argparse.Action):
     """A custom action to parse arguments as key1=value1,key2=value2 pairs
 

osc_lib/tests/cli/test_parseractions.py

@@ -59,6 +59,53 @@ class TestKeyValueAction(utils.TestCase):
                               self.parser.parse_args, data)
 
 
+class TestKeyValueAppendAction(utils.TestCase):
+
+    def setUp(self):
+        super(TestKeyValueAppendAction, self).setUp()
+
+        self.parser = argparse.ArgumentParser()
+
+        # Set up our typical usage
+        self.parser.add_argument(
+            '--hint',
+            metavar='<key=value>',
+            action=parseractions.KeyValueAppendAction,
+            help='Arbitrary key/value pairs to be sent to the scheduler for '
+                 'custom use',
+        )
+
+    def test_good_values(self):
+        print(self.parser._get_optional_actions())
+        results = self.parser.parse_args([
+            '--hint', 'same_host=a0cf03a5-d921-4877-bb5c-86d26cf818e1',
+            '--hint', 'same_host=8c19174f-4220-44f0-824a-cd1eeef10287',
+            '--hint', 'query=[>=,$free_ram_mb,1024]',
+        ])
+
+        actual = getattr(results, 'hint', {})
+        expect = {
+            'same_host': [
+                'a0cf03a5-d921-4877-bb5c-86d26cf818e1',
+                '8c19174f-4220-44f0-824a-cd1eeef10287',
+            ],
+            'query': [
+                '[>=,$free_ram_mb,1024]',
+            ],
+        }
+        self.assertEqual(expect, actual)
+
+    def test_error_values(self):
+        data_list = [
+            ['--hint', 'red', ],
+            ['--hint', '=', ],
+            ['--hint', '=red', ]
+        ]
+        for data in data_list:
+            self.assertRaises(argparse.ArgumentTypeError,
+                              self.parser.parse_args, data)
+
+
 class TestMultiKeyValueAction(utils.TestCase):
 
     def setUp(self):

releasenotes/notes/add-KeyValueAppendAction-class-f830e71152d6b91e.yaml

@@ -0,0 +1,5 @@
+---
+features:
+  - |
+    Add ``KeyValueAppendAction`` that allows key-value arguments to be specified
+    multiple times. For example: ``--property key1=value1 --property key1=value2``.