我需要以编程方式请求一些文件并发送文件作为响应。我如何通过API从 Delphi 创建一个文件请求（https://www.dropbox.com/requests），以便第三方可以用这种代码将请求的文件发送给我;

procedure TDropbox.Upload(const AFileName: String);
const
  API_URL = 'https://api-content.dropbox.com/1/files_put/sandbox/';
var
  URL: String;
  Stream: TMemoryStream;
  ShortFileName: String;
  https: TIdHTTP;
  SslIoHandler: TIdSSLIOHandlerSocket;
begin
  if not FileExists(AFileName) then
  begin
    raise EInOutError.CreateFmt('File %s not found', [AFileName]);
  end;

  ShortFileName := ExtractFileName(AFileName);
  URL := API_URL+ShortFileName
    + '?oauth_signature_method=PLAINTEXT&oauth_consumer_key=' + FAppKey
    + '&oauth_token=' + FOAuth.AccessToken
    + '&oauth_signature=' + FAppSecret + '%26' + FOAuth.AccessTokenSecret;

  https := TIdHTTP.Create(nil);
  Stream := TMemoryStream.Create;
  try
    SslIoHandler := TIdSSLIOHandlerSocket.Create(https);
    SslIoHandler.SSLOptions.Method := sslvTLSv1;
    SslIoHandler.SSLOptions.Mode := sslmUnassigned;

    https.IOHandler := SslIoHandler;
    Stream.LoadFromFile(AFileName);

    https.Post(URL, Stream);
  finally
    FreeAndNil(Stream);
    FreeAndNil(https);
  end;
end;