作为前一个问题的参考，我正在尝试获取一个txt文件上传到ipfs上，请求如下：

Future<int> downloadItemIPFS(String hash,String localFolder) async {
  String username = FlutterConfig.get('INFURA_PROJECT_ID');
  String password = FlutterConfig.get('INFURA_API_SECRET');
  String basicAuth = 'Basic ${base64.encode(utf8.encode("$username:$password"))}';
  String tmpPath = await temporaryDirectoryPath;
  Directory('$tmpPath/$localFolder/').create();
  var list = List<int>.generate(100, (i) => i)..shuffle();
  List<int> names = list.take(5).toList();
  String name = '';
  for (int i = 0; i<names.length; i++) {
    name += names[i].toString();
  }
  //var url = Uri.https('ipfs.infura.io:5001','/api/v0/get',{'arg':hash,'output': '$tmpPath/$localFolder/'});
  //http.Response response = await http.post(url, headers: {'Content-Type': "text/plain",HttpHeaders.authorizationHeader: basicAuth},);

  var url = Uri.https('ipfs.infura.io:5001','/api/v0/get',{'arg':hash ,'output': '$tmpPath/$localFolder/'});
  var request = http.MultipartRequest("POST", url);
  request.headers['Authorization'] = basicAuth;
  StreamedResponse response = await request.send();
  var result = await http.Response.fromStream(response);
  File file = await File("$tmpPath/$localFolder/$name.txt").writeAsString(result.body);
  print("Body content: ${ await file.readAsString()}");
  return response.statusCode;
}

Future<List<FileSystemEntity>> getDownloadedFiles(String folder) async {
  String tmpPath = await temporaryDirectoryPath;
  Directory dir = Directory("$tmpPath/$folder/");
  final List<FileSystemEntity> out = await dir.list().toList();
  return out;
}

我从主体的响应中只接收到文件的哈希值
我尝试在postman上提出同样的要求，收到以下回应：
screenshot 1
screenshot 2