Pascal (Lazarus/Delphi)

Get ECC Public Key in JWK Format (JSON Web Key)

See more ECC Examples

Demonstrates how to get an ECC public key in JWK (JSON Web Key) format.

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

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.PublicKey,
  Chilkat.JsonObject;

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

procedure RunDemo;
var
  success: Boolean;
  sbPem: TStringBuilder;
  pubKey: TPublicKey;
  jwk: string;
  json: TJsonObject;

begin
  success := False;

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

  //  Load a PEM file into memory.
  sbPem := TStringBuilder.Create;
  success := sbPem.LoadFile('qa_data/pem/ecc_public.pem','utf-8');
  if (success <> True) then
    begin
      WriteLn('Failed to load PEM file.');
      Exit;
    end;

  //  Load the PEM into a public key object.
  pubKey := TPublicKey.Create;
  success := pubKey.LoadFromString(sbPem.GetAsString());
  if (success <> True) then
    begin
      WriteLn(pubKey.LastErrorText);
      Exit;
    end;

  //  Get the public key in JWK format:
  jwk := pubKey.GetJwk();

  //  The GetJwk method will return the JWK in the most compact JSON format possible,
  //  as a single line with no extra whitespace.  To get a more human-readable JWK (for this example),
  //  load into a Chilkat JSON object and emit non-compact:

  json := TJsonObject.Create;
  json.Load(jwk);
  json.EmitCompact := False;
  WriteLn('ECC Public Key in JWK format:');
  WriteLn(json.Emit());

  //  Sample output:
  //  { 
  //    "kty": "EC",
  //    "crv": "P-256",
  //    "x": "oBUyo8CQAFPeYPvv78ylh5MwFZjTCLQeb042TjiMJxE",
  //    "y": "vvQyxZkUjJQUPU_0bCy3Pj5qQdfu8jwEfqEeYGZ95CU"
  //  }
  //  
  //  Additional information can be added like this:
  json.AppendString('use','enc');
  json.AppendString('kid','123ABC');

  //  Now examine the JSON:
  WriteLn(json.Emit());

  //  { 
  //    "kty": "EC",
  //    "crv": "P-256",
  //    "x": "oBUyo8CQAFPeYPvv78ylh5MwFZjTCLQeb042TjiMJxE",
  //    "y": "vvQyxZkUjJQUPU_0bCy3Pj5qQdfu8jwEfqEeYGZ95CU",
  //    "use": "enc",
  //    "kid": "123ABC"
  //  }


  sbPem.Free;
  pubKey.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.