Synapse webform submit issue
lazarus / 38-Networking and Web Programming

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djwalkowiak · 2015-01-20 06:23

Hi,

I am currently writing an app to get data from one webform, doing
something with data, and than submitting a form with file uploaded.
All works till submitting a form. Server is refusing request
continiously. I have checked with Fiddler what sort of data and
headers are being sent by browser while submitting a form a tried to
copy it, without luck. I hope you will be able to help me with this.
Here is a code submitting a form (taken from one of the posts on this
forums and modified)
Code: [Select]function HttpPostFile(const URL, FileName: string;
  const Data: TStream; const ResultData: TStrings): Boolean;
var
  HTTP: THTTPSend;
  Bound, s: string;
  Header:TStringList;
const
  CRLF = #13#10;
begin
  Bound := IntToHex(Random(MaxInt), 8) + '_Synapse_boundary';
  HTTP := THTTPSend.Create;
  Header:=TStringList.Create;
  try
    s := '--' + Bound + CRLF;
    s := s + 'Content-Disposition: form-data; name="file1";
filename="'+filename+ '"'+ CRLF;
    s := s + ' Content-Type: application/octet-stream' + CRLF + CRLF;
    s:=EncodeURLElement(s);
    WriteStrToStream(HTTP.Document, s);
    HTTP.Document.CopyFrom(Data, 0);
    s := CRLF + '--' + Bound + '--' + CRLF;
    s := s + 'Content-Disposition: form-data; name="B1"' + CRLF + CRLF
+'Upload' + CRLF; //check this!
    s := CRLF + '--' + Bound + '--' + CRLF;
    s := s + 'Content-Disposition: form-data; name="file1db"' + CRLF +
CRLF +file1db + CRLF;
    s := CRLF + '--' + Bound + '--' + CRLF;
    s:=EncodeURLElement(s);
    WriteStrToStream(HTTP.Document, s);
    Header.Add('HTTP/1.1 200 OK');
    Header.Add('Server: nginx/1.4.6');
    Header.Add('Content-Type: text/html; charset=UTF-8');
    Header.Add('Connection: keep-alive');
    Header.Add('X-Powered-By: PHP/5.3.28');
    Header.Add('Connection: keep-alive');
    Header.Add('Cache-Control: no-store, no-cache, must-revalidate,
post-check=0, pre-check=0');
    Header.Add('Pragma: no-cache');
    HTTP.MimeType := 'multipart/form-data; boundary=' + Bound;
    HTTP.UserAgent:='Safari';
    HTTP.Headers.AddStrings(Header);
    Result := HTTP.HTTPMethod('POST', URL);
    if Result then
      ResultData.LoadFromStream(HTTP.Document);
  finally
    HTTP.Free;
  end;
end;                                                               
This is an action calling the function:
Code: [Select]try
         readyfile:=TFileStream.Create(UpLink, fmOpenRead);
         List:=TStringList.Create;
    HttpPostFile(urlsave, UpLink, readyfile, List);
         memo1.Lines:=List;
        break;
            finally
        readyfile.Free;
            end;                                                     
         Where UpLink is a location of file to uploaded. It might have
something to do with server accepted encoding. It's "Accept-Encoding:
gzip, deflate", so browser is sending it as "Content-Encoding: gzip".
Also, there is something to dowith cookies, Fiddler is showing:
Code: [Select]Set-Cookie: frontend=62rgvscdej8a1pn796lk8vvid1;
expires=Mon, 19-Jan-2015 07:48:30 GMT; path=/
Any suggestions, please?