public function beforeSave()
{
$this->publish_time = strtotime($this->publish_time);
$this->update_user_id = Yii::app()->user->getId();
if ($this->getIsNewRecord()) {
$this->create_user_id = $this->update_user_id;
$this->create_user_ip = Yii::app()->getRequest()->userHostAddress;
}
$this->setTags($this->tags);
return parent::beforeSave();
}