Dart

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.

Dart

import 'package:chilkat/chilkat.dart';

void main() {
  // Note: This example requires Chilkat v9.5.0.66 or later.

  // Load a PEM file into memory.
  final sbPem = CkStringBuilder();
  try {
    sbPem.loadFile('qa_data/pem/rsa_public.pem', 'utf-8');
  } on ChilkatException {
    print('Failed to load PEM file.');
    return;
  }

  // Load the PEM into a public key object.
  final pubKey = CkPublicKey();
  try {
    pubKey.loadFromString(sbPem.getAsString());
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Get the public key in JWK format:
  final 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:

  final json = CkJsonObject();
  json.load(jwk);
  json.emitCompact = false;
  print('RSA Public Key in JWK format:');
  print(json.emit());

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

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

  // Now examine the JSON:
  print(json.emit());

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