Dart

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.

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/ecc_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('ECC Public Key in JWK format:');
  print(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:
  print(json.emit());

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