<?php
declare(strict_types=1);
namespace Kreait\Firebase\JWT;
use Kreait\Clock;
use Kreait\Clock\SystemClock;
use Kreait\Firebase\JWT\Action\FetchGooglePublicKeys;
use Kreait\Firebase\JWT\Action\FetchGooglePublicKeys\Handler;
use Kreait\Firebase\JWT\Action\FetchGooglePublicKeys\WithHandlerDiscovery;
use Kreait\Firebase\JWT\Contract\Expirable;
use Kreait\Firebase\JWT\Contract\Keys;
final class GooglePublicKeys implements Keys
{
private Clock $clock;
private Handler $handler;
private ?Keys $keys = null;
public function __construct(Handler $handler = null, Clock $clock = null)
{
$this->clock = $clock ?: new SystemClock();
$this->handler = $handler ?: new WithHandlerDiscovery($this->clock);
}
public function all(): array
{
$keysAreThereButExpired = $this->keys instanceof Expirable && $this->keys->isExpiredAt($this->clock->now());
if (!$this->keys || $keysAreThereButExpired) {
$this->keys = $this->handler->handle(FetchGooglePublicKeys::fromGoogle());
// There is a small chance that we get keys that are already expired, but at this point we're happy
// that we got keys at all. The next time this method gets called, we will re-fetch.
}
return $this->keys->all();
}
}