/**
* @param User $user
* @param int $lifetime
*/
private function generateToken(User $user, $lifetime = 86400)
{
$token = sha1(random_bytes(40));
$expireAt = new \DateTime();
$lifetime = $lifetime - $expireAt->getOffset();
// GMT
$expireAt->add(new \DateInterval('PT' . (int) $lifetime . 'S'));
$user->setApiToken($token);
$user->setApiTokenExpireAt($expireAt);
}