Kohana ORM - Empty Result on User Rights

Question

Im building a user management system based on 2 pillars.

1. Roles

Each user have multiple roles.

2. Rights

Every role consists of one or more rights.

Users and roles are working fine in my attempt:

class Model_Auth_User extends ORM {

protected $_has_many = array(
    'roles'       => array('model' => 'Role', 'through' => 'roles_users'),
);...}


class Model_Auth_Role extends ORM {

protected $_has_many = array(
    'users' => array('model' => 'User','through' => 'roles_users'),
);...}

I am trying to add some Roles and Rights the same way:

class Model_Auth_Role extends ORM {

protected $_has_many = array(
    'users' => array('model' => 'User','through' => 'roles_users'),
    'rights' => array('model' => 'Right','through' => 'role_rights'),
);



class Model_Auth_Right extends ORM {

protected $_has_many = array(
    'roles' => array('model' => 'Role','through' => 'role_rights'),
);

The access to the roles works fine like this:

$roles = $user->roles->find_all(); //works fine

However, the access to the Rights of a Role always delivers an empty result:

$rights = $user->roles->rights->find_all();

Answer 1

Because $user->roles i collection

<?php
$rights = [];
foreach($user->roles->find_all() as $role){
 $rights[] = $role->rights->find_all();
}