PHP Extension

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.

PHP Extension

<?php

include("chilkat.php");

$success = false;

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

// Load a PEM file into memory.
$sbPem = new CkStringBuilder();
$success = $sbPem->LoadFile('qa_data/pem/ecc_public.pem','utf-8');
if ($success != true) {
    print 'Failed to load PEM file.' . "\n";
    exit;
}

// Load the PEM into a public key object.
$pubKey = new CkPublicKey();
$success = $pubKey->LoadFromString($sbPem->getAsString());
if ($success != true) {
    print $pubKey->lastErrorText() . "\n";
    exit;
}

// 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 = new CkJsonObject();
$json->Load($jwk);
$json->put_EmitCompact(false);
print 'ECC Public Key in JWK format:' . "\n";
print $json->emit() . "\n";

// 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() . "\n";

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

?>