skeeks\cms\models\CmsContentProperty::rules PHP Method

    public function rules()
    {
        $rules = ArrayHelper::merge(parent::rules(), [[['content_id'], 'integer'], [['code', 'content_id'], 'unique', 'targetAttribute' => ['content_id', 'code'], 'message' => \Yii::t('skeeks/cms', 'For the content of this code is already in use.')]]);
        return $rules;
    }