Delphi ActiveX

Create JWT using a Brainpool EC Key

See more JSON Web Token (JWT) Examples

Demonstrates how to create a JWT using an EC private key. This is for JOSE headers having an "alg" member with any of the following values:

• BP160R1
• BP192R1
• BP224R1
• BP256R1
• BP320R1
• BP384R1
• BP512R1

This example also demonstrates how to include time constraints:

• nbf: Not Before Time
• exp: Expiration Time
• iat: Issue At Time

Delphi ActiveX

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Chilkat_TLB;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Integer;
privKey: TPrivateKey;
jwt: TChilkatJwt;
jose: TChilkatJsonObject;
claims: TChilkatJsonObject;
curDateTime: Integer;
token: WideString;

begin
success := 0;

// Demonstrates how to create a JWT using a brainpool EC private key.

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

privKey := TPrivateKey.Create(Self);

// Load a brainpool EC key.
success := privKey.LoadPemFile('c:/qa_data/pem/ec_brainpool_privKey.pem');
if (success <> 1) then
  begin
    Memo1.Lines.Add(privKey.LastErrorText);
    Exit;
  end;

// You can examine the curve name of the key you just loaded by getting the private in XML format:
// <ECCKeyValue curve="CURVE_NAME">...</ECCKeyValue>
Memo1.Lines.Add(privKey.GetXml());

jwt := TChilkatJwt.Create(Self);

// Build the JOSE header
jose := TChilkatJsonObject.Create(Self);
// Use the brainpool curve name matching the private key you just loaded.
// Use "BP256R1", or "BP384R1", etc.   
success := jose.AppendString('alg','BP256R1');
success := jose.AppendString('typ','JWT');

// Now build the JWT claims (also known as the payload)
claims := TChilkatJsonObject.Create(Self);
success := claims.AppendString('iss','http://example.org');
success := claims.AppendString('sub','John');
success := claims.AppendString('aud','http://example.com');

// Set the timestamp of when the JWT was created to now.
curDateTime := jwt.GenNumericDate(0);
success := claims.AddIntAt(-1,'iat',curDateTime);

// Set the "not process before" timestamp to now.
success := claims.AddIntAt(-1,'nbf',curDateTime);

// Set the timestamp defining an expiration time (end time) for the token
// to be now + 1 hour (3600 seconds)
success := claims.AddIntAt(-1,'exp',curDateTime + 3600);

// Produce the smallest possible JWT:
jwt.AutoCompact := 1;

// Create the JWT token.  This is where the ECC signature is created.
token := jwt.CreateJwtPk(jose.Emit(),claims.Emit(),privKey.ControlInterface);

Memo1.Lines.Add(token);
end;