public async void TestDetect()
{
// test no face image
IFormFile formFile = CreateFormFile("test-none.jpg");
var result = await _controller.Detect(formFile);
var jsonResult = Assert.IsType <JsonResult>(result);
List <FaceInfo> faceList = (List <FaceInfo>)jsonResult.Value;
Assert.Empty(faceList);
// test one face image
formFile = CreateFormFile("test-one.jpg");
result = await _controller.Detect(formFile);
jsonResult = Assert.IsType <JsonResult>(result);
faceList = (List <FaceInfo>)jsonResult.Value;
Assert.Single(faceList);
// test multi-face image
formFile = CreateFormFile("test-three.jpg");
result = await _controller.Detect(formFile);
jsonResult = Assert.IsType <JsonResult>(result);
faceList = (List <FaceInfo>)jsonResult.Value;
Assert.Equal(3, faceList.Count());
}