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PHP ActiveX

Export a Public Key as a JWK

Demonstrates the Chilkat PublicKey.GetJwk method, which returns the public key as a compact JWK (JSON Web Key). It takes no arguments; binary values use Base64url without padding and the member order is stable across calls.

Note: The file paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

Background: JWK is the JSON key format used across modern web security — JWT, OAuth, OpenID Connect. Exporting a public key to JWK is exactly what you do to publish it in a JWK Set (a jwks_uri endpoint) so others can verify your signatures. The stable member order matters because it makes the output reproducible, which is important when the JWK feeds into a thumbprint.

Chilkat PHP ActiveX Downloads

PHP ActiveX
<?php

$success = 0;

//  Load a public key to export.  LoadFromFile inspects the content, so it accepts DER, PEM, XML,
//  JWK, and other supported representations.
$pubKey = new COM("Chilkat.PublicKey");
$success = $pubKey->LoadFromFile('qa_data/public.pem');
if ($success == 0) {
    print $pubKey->LastErrorText . "\n";
    exit;
}

//  Export the public key as a compact JWK (JSON Web Key).  Binary values use Base64url without
//  padding, and the member order is stable across calls.
$jwk = $pubKey->getJwk();
if ($pubKey->LastMethodSuccess == 0) {
    print $pubKey->LastErrorText . "\n";
    exit;
}

print $jwk . "\n";

?>