Set empty element to ""

When serializer xml formatter response need set empty element to "" to
align with JSON formatter.

Fix bug 1168317

Change-Id: I4985791095f43eac88fe42ec16f6a78bbf77ec07

keystone/common/serializer.py

@@ -153,6 +153,10 @@ class XmlDeserializer(object):
             else:
                 values = dict(values.items() + child.items())
 
+        # set empty and none-list element to None to align with JSON
+        if not values:
+            values = ""
+
         d = {XmlDeserializer._tag_name(element.tag, namespace): values}
 
         if links:

tests/test_content_types.py

@@ -904,3 +904,53 @@ class XmlTestCase(RestfulTestCase, CoreApiTests):
                 </auth>
             """,
             expected_status=400)
+
+    def test_add_tenant_xml(self):
+        """
+        verify create a tenant without providing description field
+        """
+        token = self.get_scoped_token()
+        r = self.request(
+            port=self._admin_port(),
+            method='POST',
+            path='/v2.0/tenants',
+            headers={
+                'Content-Type': 'application/xml',
+                'X-Auth-Token': token
+            },
+            body="""
+                <?xml version="1.0" encoding="UTF-8"?>
+                <tenant xmlns="http://docs.openstack.org/identity/api/v2.0"
+                enabled="true" name="ACME Corp">
+                <description></description>
+                </tenant>
+            """)
+        self._from_content_type(r, 'json')
+        self.assertIsNotNone(r.body.get('tenant'))
+        self.assertValidTenant(r.body['tenant'])
+        self.assertEqual(r.body['tenant'].get('description'), "")
+
+    def test_add_tenant_json(self):
+        """
+        verify create a tenant without providing description field
+        """
+        token = self.get_scoped_token()
+        r = self.request(
+            port=self._admin_port(),
+            method='POST',
+            path='/v2.0/tenants',
+            headers={
+                'Content-Type': 'application/json',
+                'X-Auth-Token': token
+            },
+            body="""
+                {"tenant":{
+                    "name":"test1",
+                    "description":"",
+                    "enabled":"true"}
+                }
+            """)
+        self._from_content_type(r, 'json')
+        self.assertIsNotNone(r.body.get('tenant'))
+        self.assertValidTenant(r.body['tenant'])
+        self.assertEqual(r.body['tenant'].get('description'), "")

tests/test_serializer.py

@@ -154,6 +154,29 @@ class XmlSerializerTestCase(test.TestCase):
 
         self.assertSerializeDeserialize(d, xml)
 
+    def test_tenant_crud_no_description(self):
+        d = {
+            "tenant": {
+                "id": "1234",
+                "name": "ACME corp",
+                "description": "",
+                "enabled": True
+            }
+        }
+
+        xml = """
+            <?xml version="1.0" encoding="UTF-8"?>
+            <tenant
+                    xmlns="http://docs.openstack.org/identity/api/v2.0"
+                    enabled="true"
+                    id="1234"
+                    name="ACME corp">
+                <description></description>
+            </tenant>
+        """
+
+        self.assertSerializeDeserialize(d, xml)
+
     def test_policy_list(self):
         d = {"policies": [{"id": "ab12cd"}]}