Raise VimFaultException for unknown faults

Currently VMwareDriverException is raised for unknown
VIM faults. Sometimes clients may need to handle such
faults. Therefore it is better if we throw
VimFaultException with the fault_list set to the relevant
VIM fault class name.

Change-Id: I34f84f3ea3f5f0d6878f1d4438cf25bf22f293fd

oslo_vmware/tests/test_api.py

@@ -373,6 +373,19 @@ class VMwareAPISessionTest(base.TestCase):
             userName=api_session._session_username)
         api_session._create_session.assert_called_once_with()
 
+    def test_invoke_api_with_unknown_fault(self):
+        api_session = self._create_api_session(True)
+        fault_list = ['NotAFile']
+
+        module = mock.Mock()
+        module.api.side_effect = exceptions.VimFaultException(fault_list,
+                                                              'Not a file.')
+        ex = self.assertRaises(exceptions.VimFaultException,
+                               api_session.invoke_api,
+                               module,
+                               'api')
+        self.assertEqual(fault_list, ex.fault_list)
+
     def test_wait_for_task(self):
         api_session = self._create_api_session(True)
         task_info_list = [('queued', 0), ('running', 40), ('success', 100)]
@@ -413,7 +426,7 @@ class VMwareAPISessionTest(base.TestCase):
         api_session.invoke_api = mock.Mock(side_effect=invoke_api_side_effect)
         task = mock.Mock()
         with mock.patch.object(greenthread, 'sleep'):
-            self.assertRaises(exceptions.VMwareDriverException,
+            self.assertRaises(exceptions.VimFaultException,
                               api_session.wait_for_task,
                               task)
         api_session.invoke_api.assert_called_with(vim_util,
@@ -531,8 +544,8 @@ class VMwareAPISessionTest(base.TestCase):
 
     def test_poll_task_unknown_exception(self):
         _unknown_exceptions = {
-            'NotAFile': exceptions.VMwareDriverException,
-            'RuntimeFault': exceptions.VMwareDriverException
+            'NotAFile': exceptions.VimFaultException,
+            'RuntimeFault': exceptions.VimFaultException
         }
 
         for k, v in six.iteritems(_unknown_exceptions):