Pascal (Lazarus/Delphi)

Create JWS using the Flattened JSON Serialization Format

See more JSON Web Signatures (JWS) Examples

Creates a JSON Web Signature (JWS) containing 1 signature and output using the flattened JSON serialization format.

Note: This example requires Chilkat v9.5.0.66 or greater.

Pascal (Lazarus/Delphi)

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.StringBuilder,
  Chilkat.PrivateKey,
  Chilkat.Jws,
  Chilkat.JsonObject;

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

procedure RunDemo;
var
  success: Boolean;
  sbEccJwk: TStringBuilder;
  eccKey: TPrivateKey;
  jwsProtHdr: TJsonObject;
  jwsUnprotHdr: TJsonObject;
  jws: TJws;
  bIncludeBom: Boolean;
  payloadStr: string;
  jwsStr: string;
  json: TJsonObject;

begin
  success := False;

  //  This requires the Chilkat API to have been previously unlocked.
  //  See Global Unlock Sample for sample code.

  //  Note: This example requires Chilkat v9.5.0.66 or greater.

  //  The JWS to be created will contain one signature using an ECDSA key.

  sbEccJwk := TStringBuilder.Create;
  sbEccJwk.Append('{"kty":"EC",');
  sbEccJwk.Append('"crv":"P-256",');
  sbEccJwk.Append('"x":"f83OJ3D2xF1Bg8vub9tLe1gHMzV76e8Tus9uPHvRVEU",');
  sbEccJwk.Append('"y":"x_FEzRu9m36HLN_tue659LNpXW6pCyStikYjKIWI5a0",');
  sbEccJwk.Append('"d":"jpsQnnGQmL-YBIffH1136cspYG6-0iY7X1fCE9-E9LI"');
  sbEccJwk.Append('}');

  eccKey := TPrivateKey.Create;
  //  Note: This example loads the ECDSA key from JWK format.  Any format can be loaded
  //  into the private key object. (See the online reference documentation..)
  success := eccKey.LoadJwk(sbEccJwk.GetAsString());
  if (success <> True) then
    begin
      WriteLn(eccKey.LastErrorText);
      Exit;
    end;

  //  ---------------------------------------------------
  //  Prepare both a protected and unprotected header.

  jwsProtHdr := TJsonObject.Create;
  jwsProtHdr.AppendString('alg','ES256');

  jwsUnprotHdr := TJsonObject.Create;
  jwsUnprotHdr.AppendString('kid','myEcKey');

  //  ---------------------------------------------------
  jws := TJws.Create;

  jws.SetProtectedHeader(0,jwsProtHdr);
  jws.SetUnprotectedHeader(0,jwsUnprotHdr);

  jws.SetPrivateKey(0,eccKey);

  bIncludeBom := False;
  payloadStr := 'In our village, folks say God crumbles up the old moon into stars.';
  jws.SetPayload(payloadStr,'utf-8',bIncludeBom);

  //  ---------------------------------------------------
  //  Create the JWS.
  //  Indicate we prefer the non-compact, flattened serialization.
  jws.PreferCompact := False;
  jws.PreferFlattened := True;

  jwsStr := jws.CreateJws();
  if (jws.LastMethodSuccess <> True) then
    begin
      WriteLn(jws.LastErrorText);
      Exit;
    end;

  //  The jwsStr is contains the flattened JSON in the smallest possible size, which is a single line.
  //  To get in human-readable format, load into a Chilkat JSON object and emit..
  json := TJsonObject.Create;
  json.Load(jwsStr);
  json.EmitCompact := False;
  WriteLn(json.Emit());

  //  Sample output:

  //  { 
  //    "payload": "SW4gb3VyIHZpbGxhZ2UsIGZvbGtzIHNheSBHb2QgY3J1bWJsZXMgdXAgdGhlIG9sZCBtb29uIGludG8gc3RhcnMu",
  //    "protected": "eyJhbGciOiJFUzI1NiJ9",
  //    "header": { 
  //      "kid": "myEcKey"
  //    },
  //    "signature": "b7V2UpDPytr-kMnM_YjiQ3E0J2ucOI9LYA7mt57vccrK1rb84j9areqgQcJwOA00aWGoz4hf6sMTBfobdcJEGg"
  //  }


  sbEccJwk.Free;
  eccKey.Free;
  jwsProtHdr.Free;
  jwsUnprotHdr.Free;
  jws.Free;
  json.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.