FuelPHP Forums

Hi everyone! I'm new on FuelPHP and just started to play with it yesterday. My only issue so far is that I can't get the ORM to validate the data I want to insert.
This is the function on my controller:

function post_user()
    {
        $data = array( 
            'first_name' => input::post('first_name'), 
            'last_name'  => input::post('last_name'),
            'gender'     => input::post('gender'),
            'birth'      => input::post('birth'),
            'email'      => input::post('email'),
            'password'   => input::post('password')
            );
        $user = new Model_user($data); 
        if($user->save()){
            $this->response($data,201);
        }else{
            $this->response(null,500);
        }
    }

And this are the propertis on th Model_user:

protected static $_properties = array(
         'id',
         'first_name' => array(
             'data_type' => 'varchar',
             'label' => 'First Name',
             'validation' => array('required', 'min_length' => array(3), 'max_length' => array(32)),
             'form' => array('data_type' => 'text')
         ),
         'last_name' => array(
             'data_type' => 'varchar',
             'label' => 'Last Name',
             'validation' => array('required', 'min_length' => array(3), 'max_length' => array(100)),
             'form' => array('data_type' => 'text')
         ),
         'email' => array(
             'data_type' => 'varchar',
             'label' => 'E-mail',
             'validation' => array('required', 'min_length' => array(3), 'max_length' => array(100)),
             'form' => array('data_type' => 'text')
         ),
         'gender' => array(
             'data_type' => 'varchar',
             'label' => 'Gender',
             'form' => array('data_type' => 'select', 'options' => array('m' => 'Male', 'f' => 'Female')),
             'validation' => array('required', 'min_length' => array(1), 'max_length' => array(1)),
         ),
         'birth' => array(
    'data_type' =>'date',
    'label' => 'Birth Date',
    'validation' => array('required')
   ),
   'password' => array(
    'data_type' => 'varchar',
    'label' => 'Password',
    'validation' => array('required')
   )
     );

If I send the 'first_name' empty it stills inserts the record
Do I have to instantiate some validation object or something like that?
Thank you very much in advance I haven't been able to figure it out by myself
Guillermo