public async Task BeginTrainingAsync_WithCorrectInput_ReturnsOk()
        {
            var mockLogger            = Mock.Of <ILogger <MaintenanceController> >();
            var mockFaceClientService = Mock.Of <IFaceClientService>();

            var controller   = new MaintenanceController(mockFaceClientService, mockLogger);
            var actionResult = await controller.BeginTrainingAsync();

            Assert.NotNull(actionResult);

            Assert.IsAssignableFrom <OkResult>(actionResult);
        }
        public async Task BeginTrainingAsync_WithFaceClientServiceFault_ThrowsException()
        {
            var mockLogger            = Mock.Of <ILogger <MaintenanceController> >();
            var mockFaceClientService = new Mock <IFaceClientService>();

            mockFaceClientService
            .Setup(service => service.BeginTrainingAsync())
            .Throws <NotImplementedException>();

            var controller = new MaintenanceController(mockFaceClientService.Object, mockLogger);
            await Assert.ThrowsAsync <NotImplementedException>(async() =>
            {
                await controller.BeginTrainingAsync();
            });
        }