Switch to providing created_at field for servers

All of the current models return the creation date in created_at
with the exception of servers which are currently returned with
a created field instead.

This patch addresses this and gives the ability to get access to
both.

Change-Id: Ifbd59834080eea62dead19d18a9a11a851a4ce2e

doc/source/user/model.rst

@@ -208,6 +208,7 @@ A Server from Nova
     accessIPv6=str(),
     addresses=dict(),  # string, list(Address)
     created=str(),
+    created_at=str(),
     key_name=str(),
     metadata=dict(),  # string, string
     private_v4=str(),

openstack/cloud/_normalize.py

@@ -503,6 +503,11 @@ class Normalizer(object):
         # Protect against security_groups being None
         ret['security_groups'] = server.pop('security_groups', None) or []
 
+        # NOTE(mnaser): The Nova API returns the creation date in `created`
+        #               however the Shade contract returns `created_at` for
+        #               all resources.
+        ret['created_at'] = server.get('created')
+
         for field in _SERVER_FIELDS:
             ret[field] = server.pop(field, None)
         if not ret['networks']:

openstack/tests/unit/cloud/test_normalize.py

@@ -575,6 +575,7 @@ class TestUtils(base.TestCase):
                     u'version': 4}]},
             'adminPass': None,
             'created': u'2015-08-01T19:52:16Z',
+            'created_at': u'2015-08-01T19:52:16Z',
             'disk_config': u'MANUAL',
             'flavor': {u'id': u'bbcb7eb5-5c8d-498f-9d7e-307c575d3566'},
             'has_config_drive': True,
@@ -644,6 +645,7 @@ class TestUtils(base.TestCase):
             'cloud': '_test_cloud_',
             'config_drive': u'True',
             'created': u'2015-08-01T19:52:16Z',
+            'created_at': u'2015-08-01T19:52:16Z',
             'disk_config': u'MANUAL',
             'flavor': {u'id': u'bbcb7eb5-5c8d-498f-9d7e-307c575d3566'},
             'has_config_drive': True,

releasenotes/notes/switch-nova-to-created_at-45b7b50af6a2d59e.yaml

@@ -0,0 +1,5 @@
+---
+features:
+  - The `created` field which was returned by the Nova API is now returned as
+    `created_at` as well when not using strict mode for consistency with other
+    models.