Delphi DLL

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

See more JSON Web Signatures (JWS) Examples

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

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

Delphi DLL

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

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
sbPem: HCkStringBuilder;
pubKey: HCkPublicKey;
jwk: PWideChar;
json: HCkJsonObject;

begin
success := False;

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

// Load a PEM file into memory.
sbPem := CkStringBuilder_Create();
success := CkStringBuilder_LoadFile(sbPem,'qa_data/pem/rsa_public.pem','utf-8');
if (success <> True) then
  begin
    Memo1.Lines.Add('Failed to load PEM file.');
    Exit;
  end;

// Load the PEM into a public key object.
pubKey := CkPublicKey_Create();
success := CkPublicKey_LoadFromString(pubKey,CkStringBuilder__getAsString(sbPem));
if (success <> True) then
  begin
    Memo1.Lines.Add(CkPublicKey__lastErrorText(pubKey));
    Exit;
  end;

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

// 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 := CkJsonObject_Create();
CkJsonObject_Load(json,jwk);
CkJsonObject_putEmitCompact(json,False);
Memo1.Lines.Add('RSA Public Key in JWK format:');
Memo1.Lines.Add(CkJsonObject__emit(json));

// Sample output:
// { 
//   "kty": "RSA",
//   "n": "33TqqLR3eeUmDtHS89qF3p4MP7Wfqt2Zjj3lZjLjjCGDvwr9cJNlNDiuKboODgUiT4ZdPWbOiMAfDcDzlOxA04DDnEFGAf-kDQiNSe2ZtqC7bnIc8-KSG_qOGQIVaay4Ucr6ovDkykO5Hxn7OU7sJp9TP9H0JH8zMQA6YzijYH9LsupTerrY3U6zyihVEDXXOv08vBHk50BMFJbE9iwFwnxCsU5-UZUZYw87Uu0n4LPFS9BT8tUIvAfnRXIEWCha3KbFWmdZQZlyrFw0buUEf0YN3_Q0auBkdbDR_ES2PbgKTJdkjc_rEeM0TxvOUf7HuUNOhrtAVEN1D5uuxE1WSw",
//   "e": "AQAB"
// }

// Additional information can be added like this:
CkJsonObject_AppendString(json,'use','enc');
CkJsonObject_AppendString(json,'kid','123ABC');

// Now examine the JSON:
Memo1.Lines.Add(CkJsonObject__emit(json));

// { 
//   "kty": "RSA",
//   "n": "33TqqLR3eeUmDtHS89qF3p4MP7Wfqt2Zjj3lZjLjjCGDvwr9cJNlNDiuKboODgUiT4ZdPWbOiMAfDcDzlOxA04DDnEFGAf-kDQiNSe2ZtqC7bnIc8-KSG_qOGQIVaay4Ucr6ovDkykO5Hxn7OU7sJp9TP9H0JH8zMQA6YzijYH9LsupTerrY3U6zyihVEDXXOv08vBHk50BMFJbE9iwFwnxCsU5-UZUZYw87Uu0n4LPFS9BT8tUIvAfnRXIEWCha3KbFWmdZQZlyrFw0buUEf0YN3_Q0auBkdbDR_ES2PbgKTJdkjc_rEeM0TxvOUf7HuUNOhrtAVEN1D5uuxE1WSw",
//   "e": "AQAB",
//   "use": "enc",
//   "kid": "123ABC"
// }

CkStringBuilder_Dispose(sbPem);
CkPublicKey_Dispose(pubKey);
CkJsonObject_Dispose(json);

end;