Flutter : send image file to server

Question

in postman

in Body -> from-data i have key = image and value file of image and type of key is File

in Authorization i have Bearer Token and send token in header i have Content-Type = multipart/form-data; boundary=

and a url is 'url/id'

when i send an image i got 202 status and everything is ok

now i write some code in my flutter application

method for take image :

 Future<void> takePictureAndSend() async {
    if (_timer != null) {
      return;
    }
    try {
      XFile picture = await controller.takePicture();
      bool status = await sendImageToServer(picture);
      if (!status) {
        await Future.delayed(Duration(seconds: 5));
        XFile picture2 = await controller.takePicture();
        await sendImageToServer(picture2);
      }
    } catch (e) {
      setState(() {
        _isDetecting = false;
        _pictureCount++;
      });
      Fluttertoast.showToast(
        msg: "try again",
        toastLength: Toast.LENGTH_SHORT,
        timeInSecForIosWeb: 1,
        backgroundColor: MyColors.darkRed,
        textColor: Colors.white,
        fontSize: 16.0,
      );
    }
  }

method for send image to the server

  Future<bool> sendImageToServer(XFile picture) async {
    setState(() {
      imageLoader = true;
    });
    final SharedPreferences prefs = await SharedPreferences.getInstance();
    String apiUrl = '${MyTexts.url}/api/v1/detection/episode/${data['id']}/';
    try {
      File fileImage = File(picture.path);
      var request = http.MultipartRequest('POST', Uri.parse(apiUrl));
      request.headers['Authorization'] = 'Bearer $_token';
      request.headers['Content-Type'] = 'multipart/form-data';
      var fileTemp = await http.MultipartFile.fromPath('image', File(picture.path).path);
      request.files.add(fileTemp);
      var response = await request.send();
      if (response.statusCode == 202) {
        final responseBytes = await response.stream.toBytes();
        final imageBytes = responseBytes.buffer.asUint8List();
    
        setState(() {
          tryAgain = false;
          showResult = true;
          greenBorder = true;
          resultImage = imageBytes;
          imageLoader = false;
        });

        Fluttertoast.showToast(
          msg: "nice",
          toastLength: Toast.LENGTH_SHORT,
          timeInSecForIosWeb: 1,
          backgroundColor: MyColors.greenNavigation,
          textColor: Colors.white,
          fontSize: 16.0,
        );
        Future.delayed(Duration(seconds: 5), () async {
          setState(() {
            showResult = false;
          });
          if (data['next_episode'] != null) {
            await loadData(MyTexts.url + data['next_episode']);
          } else {
            if (Navigator.canPop(context)) {
              Navigator.pop(context);
            }
          }
        });
        return true;
      }
      else {
        setState(() {
          imageLoader = false;
        });
        _takePicture();
        return false;
      }
    } catch (e) {
      print('errorrrrrrrrrrrr  $e');
      setState(() {
        tryAgain = true;
      });
      return false;
    }
  }

but in my code i gote status 500 when i send an image to the server

and as i know this line request.files.add(fileTemp); return empty {}

so how can i fix my code ?