Capture the Composed REST Request for Debugging

See more REST Examples

Demonstrates Rest.GetLastDebugRequest, which copies the fully composed HTTP request (request line, headers, and body) into a BinData. The example builds a two-part multipart request so the captured output shows the multipart boundaries, part headers, and part bodies. This works when the DebugMode property was enabled while the request was composed.

program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.BinData,
  Chilkat.Rest;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  success: Boolean;
  rest: TRest;
  bTls: Boolean;
  bAutoReconnect: Boolean;
  bdRequest: TBinData;
  requestText: string;

begin
  success := False;

  rest := TRest.Create;
  bTls := True;
  bAutoReconnect := True;
  success := rest.Connect('example.com',443,bTls,bAutoReconnect);
  if (success = False) then
    begin
      WriteLn(rest.LastErrorText);
      Exit;
    end;

  //  Enable debug mode so the fully composed HTTP request is captured instead of being sent.
  rest.DebugMode := True;

  //  Build a multipart request with two parts.  The captured debug output will show the multipart
  //  boundaries, part headers, and part bodies.
  rest.PartSelector := '1';
  rest.AddHeader('Content-Type','text/plain');
  rest.AddHeader('Content-Disposition','form-data; name="field1"');
  success := rest.SetMultipartBodyString('value1');
  if (success = False) then
    begin
      WriteLn(rest.LastErrorText);
      Exit;
    end;

  rest.PartSelector := '2';
  rest.AddHeader('Content-Type','application/json');
  rest.AddHeader('Content-Disposition','form-data; name="metadata"');
  success := rest.SetMultipartBodyString('{ "active": true }');
  if (success = False) then
    begin
      WriteLn(rest.LastErrorText);
      Exit;
    end;

  //  Compose the multipart request.  In debug mode the request is built but not transmitted.
  success := rest.SendReqMultipart('POST','/api/upload');
  if (success = False) then
    begin
      WriteLn(rest.LastErrorText);
      Exit;
    end;

  //  Copy the composed request (request line, headers, and multipart body that would be sent) into a
  //  BinData, then view it as text.
  bdRequest := TBinData.Create;
  rest.GetLastDebugRequest(bdRequest);

  requestText := bdRequest.GetString('utf-8');
  if (bdRequest.LastMethodSuccess = False) then
    begin
      WriteLn(bdRequest.LastErrorText);
      Exit;
    end;
  WriteLn(requestText);


  rest.Free;
  bdRequest.Free;

end;

// ---------------------------------------------------------------------------

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.