Delphi Client-side POST / Upload

     with IdHTTP do
     begin
          HTTPOptions     := [hoForceEncodeParams];
          AllowCookies    := True;
          HandleRedirects := True;
          ProtocolVersion := pv1_1;
     end;    // with

     Stream          := TIdMultipartFormDataStream.Create;

     EncodedFileName := TIdEncoderMIME.EncodeString(ExtractFileName(Trim(FileName)), IndyUTF8Encoding);
     EncodedFileName := StringReplace(EncodedFileName, '+', '-', [rfReplaceAll, rfIgnoreCase]);
     EncodedFileName := StringReplace(EncodedFileName, '/', '_', [rfReplaceAll, rfIgnoreCase]);
     EncodedFileName := StringReplace(EncodedFileName, '=', ',', [rfReplaceAll, rfIgnoreCase]);

     with Stream.AddFormField('file_name', EncodedFileName, 'utf-8') do
     begin
          HeaderCharset  := 'utf-8';
          HeaderEncoding := '8';
     end;    // with

     IdHttp.Head('http://domain.com/data/my-file.zip');
     ByteRange       := Http.Response.ContentLength;

     // TODO: Get the rest of the file that corresponds to [ByteRange-...]

     with Stream.AddFile('upload_file', FileName, 'application/octet-stream') do
     begin
          HeaderCharset  := 'utf-8';
          HeaderEncoding := '8';
     end;    // with

     PostStatus      := Trim(IdHTTP.Post(POST_URL, Stream));