Extensions

<?php

declare(strict_types=1);

namespace Acme\Extension;

use Webauthn\AuthenticationExtensions\ExtensionOutputChecker;
use Webauthn\AuthenticationExtensions\ExtensionOutputError;

final class LocationExtensionOutputChecker
{
    public function check(AuthenticationExtensionsClientInputs $inputs, AuthenticationExtensionsClientOutputs $outputs): void
    {
        if (!$inputs->has('uvm') || $inputs->get('uvm') !== true) {
            return;
        }

        if (!$outputs->has('uvm')) {
            //You may simply return but here we consider it is a mandatory extension output.
            throw new ExtensionOutputError(
                $inputs->get('uvm'),
                'The User Verification Method is missing'
            );
        }

        $uvm = $outputs->get('uvm');
        //... Proceed with the output
    }
}

webauthn:
    …
    creation_profiles:
        default:
            rp:
                name: 'My Application'
                id: 'example.com'
            extensions:
                uvm: true
    request_profiles:
        default:
            rp_id: 'example.com'
            extensions:
                uvm: true