Handle booleans that are strings in APIs

Coerces string values to a boolean only when the prop is given a
type=BoolStr. BoolStr only accepts string words, no shortened values,
synonyms or integer values. When no acceptable value is found a
TypeError or ValueError is raised. Setters and Constructor calls
validate the attribute value as a fail-fast behavior.

Change-Id: I382426325522227a83ec5234c5116da97e71cfa2
Closes-Bug: #1365724

openstack/format.py

@@ -0,0 +1,40 @@
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+
+class BoolStr(object):
+    """A custom boolean/string hybrid type for resource.props.
+
+    Translates a given value to the desired type.
+    """
+    def __init__(self, given):
+        """A boolean parser.
+
+        Interprets the given value as a boolean, ignoring whitespace and case.
+        A TypeError is raised when interpreted as neither True nor False.
+        """
+        expr = str(given).lower()
+        if 'true' == expr:
+            self.parsed = True
+        elif 'false' == expr:
+            self.parsed = False
+        else:
+            msg = 'Invalid as boolean: %s' % given
+            raise ValueError(msg)
+
+    def __bool__(self):
+        return self.parsed
+
+    __nonzero__ = __bool__
+
+    def __str__(self):
+        return str(self.parsed)

openstack/identity/v2/role.py

@@ -10,6 +10,7 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
+from openstack import format
 from openstack.identity import identity_service
 from openstack import resource
 
@@ -30,4 +31,4 @@ class Role(resource.Resource):
     # Properties
     description = resource.prop('description')
     name = resource.prop('name')
-    enabled = resource.prop('enabled')  # API implements as string
+    enabled = resource.prop('enabled', type=format.BoolStr)

openstack/resource.py

@@ -66,13 +66,24 @@ class prop(object):
 
     def __get__(self, instance, owner):
         try:
-            return instance._attrs[self.name]
+            value = instance._attrs[self.name]
         except KeyError:
             raise AttributeError('Unset property: %s' % self.name)
 
+        if self.type and not isinstance(value, self.type):
+            value = self.type(value)
+            attr = getattr(value, 'parsed', None)
+            if attr is not None:
+                value = attr
+
+        return value
+
     def __set__(self, instance, value):
         if self.type and not isinstance(value, self.type):
-            raise TypeError('Invalid type for attr %s' % self.name)
+            try:
+                value = str(self.type(value))  # validate to fail fast
+            except AttributeError:
+                raise TypeError('Invalid type for attr: %s' % self.name)
 
         instance._attrs[self.name] = value
 
@@ -127,6 +138,11 @@ class Resource(collections.MutableMapping):
             attrs = {}
 
         self._attrs = attrs
+        # ensure setters are called for type coercion
+        for k, v in attrs.items():
+            if k != 'id':  # id property is read only
+                setattr(self, k, v)
+
         self._dirty = set() if loaded else set(attrs.keys())
         self._loaded = loaded
         if not self.resource_name:

openstack/tests/identity/v2/test_role.py

@@ -39,7 +39,7 @@ class TestRole(testtools.TestCase):
 
     def test_make_it(self):
         sot = role.Role(EXAMPLE)
-        self.assertEqual(EXAMPLE['enabled'], sot.enabled)
+        self.assertEqual(True, sot.enabled)
         self.assertEqual(EXAMPLE['description'], sot.description)
         self.assertEqual(EXAMPLE['id'], sot.id)
         self.assertEqual(EXAMPLE['name'], sot.name)

openstack/tests/network/v2/test_port.py

@@ -17,16 +17,16 @@ from openstack.network.v2 import port
 IDENTIFIER = 'IDENTIFIER'
 EXAMPLE = {
     'admin_state_up': True,
-    'allowed_address_pairs': '2',
+    'allowed_address_pairs': {'2': 2},
     'binding:host_id': '3',
     'binding:profile': '4',
-    'binding:vif_details': '5',
+    'binding:vif_details': {'5': 5},
     'binding:vif_type': '6',
     'binding:vnic_type': '7',
     'device_id': '8',
     'device_owner': '9',
-    'extra_dhcp_opts': '10',
-    'fixed_ips': '11',
+    'extra_dhcp_opts': {'10': 10},
+    'fixed_ips': {'11': '12'},
     'id': IDENTIFIER,
     'mac_address': '13',
     'name': '14',

openstack/tests/network/v2/test_router.py

@@ -18,7 +18,7 @@ from openstack.network.v2 import router
 IDENTIFIER = 'IDENTIFIER'
 EXAMPLE = {
     'admin_state_up': True,
-    'external_gateway_info': '2',
+    'external_gateway_info': {'2': '3'},
     'id': IDENTIFIER,
     'name': '4',
     'tenant_id': '5',

openstack/tests/test_format.py

@@ -0,0 +1,41 @@
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+import testtools
+
+from openstack import format
+
+
+class TestFormat(testtools.TestCase):
+    def test_parse_true(self):
+        self.assertEqual(True, format.BoolStr(True).parsed)
+        self.assertEqual(True, format.BoolStr('True').parsed)
+        self.assertEqual(True, format.BoolStr('TRUE').parsed)
+        self.assertEqual(True, format.BoolStr('true').parsed)
+
+    def test_parse_false(self):
+        self.assertEqual(False, format.BoolStr(False).parsed)
+        self.assertEqual(False, format.BoolStr('False').parsed)
+        self.assertEqual(False, format.BoolStr('FALSE').parsed)
+        self.assertEqual(False, format.BoolStr('false').parsed)
+
+    def test_parse_fails(self):
+        self.assertRaises(ValueError, format.BoolStr, None)
+        self.assertRaises(ValueError, format.BoolStr, '')
+        self.assertRaises(ValueError, format.BoolStr, 'INVALID')
+
+    def test_to_str_true(self):
+        self.assertEqual('True', str(format.BoolStr(True)))
+        self.assertEqual('True', str(format.BoolStr('True')))
+
+    def test_to_str_false(self):
+        self.assertEqual('False', str(format.BoolStr('False')))
+        self.assertEqual('False', str(format.BoolStr(False)))

openstack/tests/test_resource.py

@@ -16,6 +16,7 @@ import httpretty
 import mock
 
 from openstack import exceptions
+from openstack import format
 from openstack import resource
 from openstack import session
 from openstack.tests import base
@@ -34,6 +35,7 @@ fake_base_path = '/fakes/%(name)s/data'
 fake_path = '/fakes/rey/data'
 
 fake_data = {'id': fake_id,
+             'enabled': True,
              'name': fake_name,
              'attr1': fake_attr1,
              'attr2': fake_attr2}
@@ -49,6 +51,7 @@ class FakeResource(resource.Resource):
     allow_create = allow_retrieve = allow_update = True
     allow_delete = allow_list = allow_head = True
 
+    enabled = resource.prop('enabled', type=format.BoolStr)
     name = resource.prop('name')
     first = resource.prop('attr1')
     second = resource.prop('attr2')
@@ -84,6 +87,7 @@ class ResourceTests(base.TestTransportBase):
         self.stub_url(httpretty.POST, path=fake_path, json=fake_body)
 
         obj = FakeResource.new(name=fake_name,
+                               enabled=True,
                                attr1=fake_attr1,
                                attr2=fake_attr2)
 
@@ -92,16 +96,19 @@ class ResourceTests(base.TestTransportBase):
 
         last_req = httpretty.last_request().parsed_body[fake_resource]
 
-        self.assertEqual(3, len(last_req))
+        self.assertEqual(4, len(last_req))
+        self.assertEqual('True', last_req['enabled'])
         self.assertEqual(fake_name, last_req['name'])
         self.assertEqual(fake_attr1, last_req['attr1'])
         self.assertEqual(fake_attr2, last_req['attr2'])
 
         self.assertEqual(fake_id, obj.id)
+        self.assertEqual('True', obj['enabled'])
         self.assertEqual(fake_name, obj['name'])
         self.assertEqual(fake_attr1, obj['attr1'])
         self.assertEqual(fake_attr2, obj['attr2'])
 
+        self.assertEqual(True, obj.enabled)
         self.assertEqual(fake_name, obj.name)
         self.assertEqual(fake_attr1, obj.first)
         self.assertEqual(fake_attr2, obj.second)
@@ -330,3 +337,17 @@ class TestFind(base.TestCase):
         self.assertEqual(fake_attr2, faker.id)
         faker.id_attribute = 'id'
         self.assertEqual(fake_id, faker.id)
+
+    def test_boolstr_prop(self):
+        faker = FakeResource(fake_data)
+        self.assertEqual(True, faker.enabled)
+        self.assertEqual('True', faker['enabled'])
+
+        faker.enabled = False
+        self.assertEqual(False, faker.enabled)
+        self.assertEqual('False', faker['enabled'])
+
+        # should fail fast
+        def set_invalid():
+            faker.enabled = 'INVALID'
+        self.assertRaises(ValueError, set_invalid)