public async void Should_ReturnErrorMessage_When_ServerIsNotResponding()
        {
            // Arrange
            var mockRepo = new Mock <IMeasureDistanceService>();

            mockRepo.Setup(repo => repo.Get("", "")).ReturnsAsync(GetInvalidDistance());
            var controller = new MeasureDistanceController(mockRepo.Object);

            // Act
            var result = await controller.Get("", "");

            // Assert
            Assert.NotNull(result.ErrorMessage);
        }
        public async void Should_ReturnAValidResult_When_AirportDataIsReturned()
        {
            // Arrange
            var mock = new Mock <IMeasureDistanceService>();

            mock.Setup(service => service.Get("AMS", "SKP")).ReturnsAsync(GetValidDistance());
            var controller = new MeasureDistanceController(mock.Object);

            // Act
            var result = await controller.Get("AMS", "SKP");

            // Assert
            Assert.IsType <DistanceDTO>(result);
        }