@Test
public void shouldParseSecurityGroupError() {

    // given
    String response = "{\"computeFault\": {\"message\": \"The server has either erred or is incapable of performing the requested operation.\", \"code\": 500}}";
    OpenstackFirewallingClientImpl openstackFirewallingClient = new OpenstackFirewallingClientImpl();
    // when
    String message = openstackFirewallingClient.parseOpenStackError(response);
    // then
    assertEquals("The server has either erred or is incapable of performing the requested operation.", message);
}