Decrypt a JWE into a StringBuilder

See more JSON Web Encryption (JWE) Examples

Demonstrates Jwe.DecryptSb, which decrypts a recipient of a loaded JWE and writes the plaintext into a StringBuilder.

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.Jwe,
  Chilkat.StringBuilder;

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

procedure RunDemo;
var
  success: Boolean;
  jwe: TJwe;
  jweCompact: string;
  base64Key: string;
  sbContent: TStringBuilder;

begin
  success := False;

  jwe := TJwe.Create;

  //  Load the JWE compact serialization to be decrypted.
  jweCompact := 'eyJhbGciOiJBMjU2S1ciLCJlbmMiOiJBMjU2R0NNIn0.<...>.<iv>.<ciphertext>.<tag>';
  success := jwe.LoadJwe(jweCompact);
  if (success = False) then
    begin
      WriteLn(jwe.LastErrorText);
      Exit;
    end;

  //  The 256-bit key-wrapping key (base64) for recipient index 0.  In production, obtain the key
  //  from a secure source rather than hard-coding it.
  base64Key := 'YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4eXowMTIzNDU=';
  success := jwe.SetWrappingKey(0,base64Key,'base64');
  if (success = False) then
    begin
      WriteLn(jwe.LastErrorText);
      Exit;
    end;

  //  Decrypt recipient index 0, writing the plaintext into a StringBuilder.
  sbContent := TStringBuilder.Create;
  success := jwe.DecryptSb(0,'utf-8',sbContent);
  if (success = False) then
    begin
      WriteLn(jwe.LastErrorText);
      Exit;
    end;
  WriteLn(sbContent.GetAsString());


  jwe.Free;
  sbContent.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.