Symfony2 collection of Entities - how to add/remove association with existing entities?

Question

1. Quick overview

1.1 Goal

What I\'m trying to achieve is a create/edit user tool. Editable fields are:

• username (type: text)
• plai

Answer 1

1. The workaround solution

The workaround solution suggested by Jeppe Marianger-Lam is at the moment the only one working I know of.

1.1 Why did it stop working in my case?

I changed my RoleNameType (for other reasons) to:

• ID (hidden)
• name (custom type - label)
• module & description (hidden, read-only)

The problem was my custom type label rendered NAME property as

     role name 

And since it was not "read only" the FORM component expected to get NAME in POST.

Instead only ID was POSTed, and thus FORM component assumed NAME is NULL.

This lead to CASE 2 (3.2) -> creating association, but overwriting ROLE NAME with an empty string.

2. So, what exacly is this workaround about?

2.1 Controller

This workaround is very simple.

In your controller, before you VALIDATE the form, you have to fetch the posted entity identyficators and get matching entities, then set them to your object.

// example action
public function createAction(Request $request)
{      
    $em = $this->getDoctrine()->getEntityManager();

    // the workaround code is in updateUser function
    $user = $this->updateUser($request, new User());

    $form = $this->createForm(new UserType(), $user);

    if($request->getMethod() == 'POST') {
        $form->bindRequest($request);

        if($form->isValid()) {
            /* Persist, flush and redirect */
            $em->persist($user);
            $em->flush();
            $this->setFlash('avocode_user_success', 'user.flash.user_created');
            $url = $this->container->get('router')->generate('avocode_user_show', array('id' => $user->getId()));

            return new RedirectResponse($url);
        }
    }

    return $this->render('AvocodeUserBundle:UserManagement:create.html.twig', array(
      'form' => $form->createView(),
      'user' => $user,
    ));
}

And below the workaround code in updateUser function:

protected function updateUser($request, $user)
{
    if($request->getMethod() == 'POST')
    {
      // getting POSTed values
      $avo_user = $request->request->get('avo_user');

      // if no roles are posted, then $owned_roles should be an empty array (to avoid errors)
      $owned_roles = (array_key_exists('avoRoles', $avo_user)) ? $avo_user['avoRoles'] : array();

      // foreach posted ROLE, get it's ID
      foreach($owned_roles as $key => $role) {
        $owned_roles[$key] = $role['id'];
      }

      // FIND all roles with matching ID's
      if(count($owned_roles) > 0)
      {
        $em = $this->getDoctrine()->getEntityManager();
        $roles = $em->getRepository('AvocodeUserBundle:Role')->findById($owned_roles);

        // and create association
        $user->setAvoRoles($roles);
      }

    return $user;
}

For this to work your SETTER (in this case in User.php entity) must be:

public function setAvoRoles($avoRoles)
{
    // first - clearing all associations
    // this way if entity was not found in POST
    // then association will be removed

    $this->getAvoRoles()->clear();

    // adding association only for POSTed entities
    foreach($avoRoles as $role) {
        $this->addAvoRole($role);
    }

    return $this;
}

3. Final thoughts

Still, I think this workaround is doing the job that

$form->bindRequest($request);

should do! It's either me doing something wrong, or symfony's Collection form type is not complete.

There are some major changes in Form component comeing in symfony 2.1, hopefully this will be fixed.

PS. If it's me doing something wrong...

... please post the way it should be done! I'd be glad to see a quick, easy and "clean" solution.

PS2. Special thanks to:

Jeppe Marianger-Lam and userfriendly (from #symfony2 on IRC). You've been very helpful. Cheers!