'Test including/excluding fields per namespace.'

def test_fields_validation(self):

    with self.assertRaises(errors.InvalidConfiguration):
        NamespaceConfig(namespace_options={'db.col': {'includeFields': ['a'], 'excludeFields': ['b']}})
    with self.assertRaises(errors.InvalidConfiguration):
        NamespaceConfig(include_fields=['a'], namespace_options={'db.col': {'excludeFields': ['b']}})
    with self.assertRaises(errors.InvalidConfiguration):
        NamespaceConfig(exclude_fields=['b'], namespace_options={'db.col': {'includeFields': ['a']}})
