/**
  * Extract values from an object
  *
  * @param  UserEntityInterface $object
  * @return array
  * @throws Exception\InvalidArgumentException
  */
 public function extract($object)
 {
     $this->guardUserObject($object);
     $data = parent::extract($object);
     return $this->mapField('id', 'user_id', $data);
 }
 /**
  * {@inheritDoc}
  * @throws PluginException
  */
 public function extract($object)
 {
     return array_merge(parent::extract($object), $this->extractFromPlugins($object));
 }