vmware: check for response body in error conditions

The response may not have a body in certain error conditions, like
a 500 on a socket error as seen in the VMware NSX CI. This fixes
an AttributeError when trying to access the response body in those
cases.

Change-Id: I086bb5bdb59813d326d45b5f7545da2ebb12aa95
Closes-Bug: #1517275

glance_store/_drivers/vmware_datastore.py

@@ -531,7 +531,7 @@ class Store(glance_store.Store):
                        '\nThe response body:\n%(body)s') %
                    {'image': image_id,
                     'status': res.status,
-                    'body': res.body})
+                    'body': getattr(res, 'body', None)})
             LOG.error(msg)
             raise exceptions.BackendException(msg)
 

glance_store/tests/unit/test_vmware_store.py

@@ -70,10 +70,12 @@ class FakeHTTPConnection(object):
 
     def __init__(self, status=200, *args, **kwargs):
         self.status = status
+        self.no_response_body = kwargs.get('no_response_body', False)
         pass
 
     def getresponse(self):
-        return utils.FakeHTTPResponse(status=self.status)
+        return utils.FakeHTTPResponse(status=self.status,
+                                      no_response_body=self.no_response_body)
 
     def request(self, *_args, **_kwargs):
         pass
@@ -447,6 +449,22 @@ class TestStore(base.StoreBaseTest,
                               self.store.add,
                               expected_image_id, image, expected_size)
 
+    @mock.patch.object(vm_store.Store, 'select_datastore')
+    @mock.patch.object(api, 'VMwareAPISession')
+    def test_unexpected_status_no_response_body(self, mock_api_session,
+                                                mock_select_datastore):
+        expected_image_id = str(uuid.uuid4())
+        expected_size = FIVE_KB
+        expected_contents = b"*" * expected_size
+        image = six.BytesIO(expected_contents)
+        self.session = mock.Mock()
+        with self._mock_http_connection() as HttpConn:
+            HttpConn.return_value = FakeHTTPConnection(status=500,
+                                                       no_response_body=True)
+            self.assertRaises(exceptions.BackendException,
+                              self.store.add,
+                              expected_image_id, image, expected_size)
+
     @mock.patch.object(api, 'VMwareAPISession')
     def test_reset_session(self, mock_api_session):
         self.store.reset_session()

glance_store/tests/utils.py

@@ -46,7 +46,8 @@ class FakeHTTPResponse(object):
         self.read = self.data.read
         self.status = status
         self.headers = headers or {'content-length': len(data)}
-        self.body = None
+        if not kwargs.get('no_response_body', False):
+            self.body = None
 
     def getheader(self, name, default=None):
         return self.headers.get(name.lower(), default)