code: public function read($sessionId) {
          $cookies = $this->getRequest()->cookies;
  
          $content = @unserialize($cookies->get($this->name, ''));
  
          if ($content === false || count($content) !== 2 ||
              !isset($content[0]) || !isset($content[1])) {
              $content = [time(), ''];
          }
  
          list($expire, $data) = $content;
  
          if($expire !== 0 && $expire < strtotime('now')) {
              return '';
          }
  
          return $data;
      }
docs: {@inheritdoc}