如何在Yii中使用jSON为对象创建其他必需字段

Question

I have a project to create a flexible information system. In this project I use a relational database (MySQL) and the Yii framework. Sometimes I have objects that can collect different information according to the id of the objecttype.

Basically, I have an object, which has an objecttype. In the objecttype table i have an info field which will contain a jSON with the description of the additional fields that I will require from the user at the moment of the new object creation.

http://www.bedoya.co/screenshots/object-objecttype-relation.png

Ok, now, with PHP I will collect the contents from objecttype_info (stored there as a jSON) and I will generate an array similar to this one:

<?php
    $x = array(
        'name'      => 'Cool name to put in the fieldset label of this object type',
        'fields'        => array( // List of additional fields that describe this object
            'field1'    => array(
                'label'         => 'Field1 label',
                'type'          => 'text',
                'htmlOptions'   => array(
                    'class'     => 'field1-class'
                    'id'        => 'field1-id'
                    'required'  => true
                )
            ),
            'campo2'    => array(
                'label'         => 'Field2 label',
                'type'          => 'number',
                'htmlOptions'   => array(
                    'class'     => 'field2-class'
                    'id'        => 'field2-id'
                    'required'  => false
                )
            ),
        )
    );

Now, I get the required values with the easy function:

<?php
    $x = ObjectType::model()->findByPk( $objecttype_id )->attributes[ 'objecttype_info' ];
?>

I don't know how to set the validation rules for the fields obtained from the objecttype. Any ideas? Am I doing this right?