Symfony2 form entity field with many-to-many relationship - symfony

Question

I have a Doctrine user entity that has a many-to-many relationship with a roles entity. I also have a form that displays user details in it based on the user entity fields. I'm setting up the form in the normal way, in my controller using the form builder, and passing in an entity instance loaded from the database. This all works fine.
Now, what I want is a select menu(s) in this form with the role(s) the user is assigned to selected, and populated from the available roles in the database. I have created a field in my UserType form called roles that has a type of 'collection' and passed in a RoleType form instance. In my RoleType form I am adding a field with type entity and defining my role class etc. This is all as per the documentation. This all works fine, it loads the select menu populated with the Roles BUT it doesn't select the correct roles saved against the user entity.
When I trace through the form value for 'roles' (or set up a data transformer on my roles entity field) the value I am getting is a string containing the name of the role that the user is associated with. I am not getting a Role instance or a Collection/Array. Also, if I set the role entity field to be multiple = true, I get a Expected a Doctrine\Common\Collections\Collection object. error from a doctrine data transformer. Again, this is because it is expecting a collection and getting a string.
Could this be something do with the way my user entity is being hydrated? I am using $repository->findOneBy(array('id' => $id));
This is a simplified version of what I am doing:
User Class
class User implements AdvancedUserInterface, \Serializable
{
/**
* #ORM\ManyToMany(targetEntity="Role", inversedBy="users")
*/
public $roles;
public function __construct()
{
$this->roles = new ArrayCollection();
}
public function getRoles()
{
return $this->roles->toArray();
}
}
Role Class
class Role implements RoleInterface
{
/**
* #ORM\ManyToMany(targetEntity="User", inversedBy="roles")
*/
public $users;
public function __construct()
{
$this->users = new ArrayCollection();
}
public function getUsers()
{
return $this->users;
}
}
User Form Type
class UserType extends AbstractType
{
public function setDefaultOptions(OptionsResolverInterface $resolver)
{
$resolver->setDefaults(array(
'data_class' => 'NameSpace\MyBundle\Entity\User',
));
}
public function buildForm(FormBuilderInterface $builder, array $options)
{
$builder->add('id', 'hidden')
->add('roles', 'collection', array('type' => new RoleType()))
->add('save', 'submit');
}
public function getName()
{
return 'user';
}
}
Role Form Type
class RoleType extends AbstractType
{
public function setDefaultOptions(OptionsResolverInterface $resolver)
{
$resolver->setDefaults(array(
'data_class' => 'NameSpace\MyBundle\Entity\Role',
));
}
public function buildForm(FormBuilderInterface $builder, array $options)
{
$builder->add('name', 'entity', array(
'class' => 'NameSpace\MyBundle\Entity\Role',
'property' => 'name'
[multiple => true]
));
}
public function getName()
{
return 'role';
}
}

Answer 1

You are not providing a collection to your form from the user entity for roles:
public function getRoles()
{
//this returns an array
return $this->roles->toArray();
}
The form class uses the getters and setters from your entity so you are actually returning an array because that is what the Symfony2 security system needs. What you need to do is also implement a getRolesCollection field and use that in the form instead:
public function getRolesCollection()
{
//this returns a collection
return $this->roles;
}
//and (updated from comment below)
->add('roles_collection', 'entity', array('type' => new RoleType()))
The oro platform do something like this: https://github.com/orocrm/platform/blob/master/src/Oro/Bundle/UserBundle/Form/Type/UserType.php
This blog post may also be helpful: http://blog.jmoz.co.uk/symfony2-fosuserbundle-role-entities/
It is a guy adding roles in the database for the FOSUserBundle