public void GetBeerById_WhenIdIsEmptyString_ShouldReturnBadRequestWithMessage()
{
// Arrange
var expectedMessge = "Beer ID is mandatory";
// Act
IHttpActionResult result = _beersController.GetBeerById(String.Empty);
// Assert
Assert.NotNull(result);
var badRequestErrorMessageResult = result as BadRequestErrorMessageResult;
Assert.NotNull(badRequestErrorMessageResult);
Assert.Equal(expectedMessge, badRequestErrorMessageResult.Message);
}