Symfony 3.2 FOSMessageBundle '.../new' (ie compose new message) throws error no matter what I do

Question

I'm not using FOSUserBundle (there's custom user/security code already in place). I've been following the docs here.

After much googling and digging through both Symfony and FOSMessageBundle files, I've come to believe that the issue has something to do with the new NewThreadMessageFormFactory class. It only has one method. If I leave it as is like so

    public function create()
    {
        return $this->formFactory->createNamed(
          $this->formName, 
          $this->formType, 
          $this->createModelInstance());
    }

I get this error Expected argument of type "string", "AppBundle\Service\NewThreadMessageFormType" given. On the other hand, if I do the following,

public function create()
{
    return $this->formFactory->createNamed(
      $this->formName,
      'AppBundle\Service\NewThreadMessageFormType', 
      $this->createModelInstance());
}

I get this Could not load type "FOS\UserBundle\Form\Type\UsernameFormType. Which, of course, doesn't even exist because FOSUserBundle isn't even installed.

I've already spent more than a dozen hours on this. I've learned a lot in the process, but I still can't make the darn thing work...

---

And my current configuration

//config.yml
fos_message:
    db_driver: orm
    thread_class: AppBundle\Entity\Thread
    message_class: AppBundle\Entity\Message
    new_thread_form:
        type: app.new_thread_form_type
        factory: app.new_thread_form_factory

and...

  //services.yml
  fos_user.user_to_username_transformer:
      alias: app.user_to_username_transformer

  app.user_to_username_transformer:
      class: AppBundle\Form\DataTransformer\UserToUsernameTransformer
      arguments:
          type: "service"
          id: "doctrine"

  app.new_thread_form_type:
      class: AppBundle\Service\NewThreadMessageFormType
      arguments: ['@app.user_to_username_transformer']
      tags:
          - {name: form.type}

  app.new_thread_form_factory:
      class: AppBundle\Service\NewThreadMessageFormFactory
      arguments: [
          '@form.factory',
          '@fos_message.new_thread_form.type',
          '%fos_message.new_thread_form.name%',
          '%fos_message.new_thread_form.model%'
          ]

Answer 1

If you are not using the FOSUSerBundle, then you need to do the following:

1. Create the UserToUsernameTransformer class as in the guide Using other UserBundles

2. In config.yml:

   fos_message:
       db_driver: orm
       thread_class: AppBundle\Entity\Thread
       message_class: AppBundle\Entity\Message
       new_thread_form:
           type: AppBundle\Form\Type\NewThreadMessageFormType
   

3. Register the services:

   app.user_to_username_transformer:
       class: AppBundle\Form\DataTransformer\UserToUsernameTransformer
       arguments: ['@doctrine']
   fos_user.user_to_username_transformer:
       alias: app.user_to_username_transformer
   app.form.type.username:
       class: AppBundle\Form\Type\UsernameFormType
       arguments: ['@app.user_to_username_transformer']
       tags:
           - { name: form.type }
   

4. Create a NewThreadMessageFormType form type class to override the default one.

   class NewThreadMessageFormType extends AbstractType
   {
       public function buildForm(FormBuilderInterface $builder, array $options)
       {
           $builder
               ->add('recipient', UsernameFormType::class, array(
                   'label' => 'recipient',
                   'translation_domain' => 'FOSMessageBundle',
               ))
           ->add('subject', TextType::class, array(
               'label' => 'subject',
               'translation_domain' => 'FOSMessageBundle',
           ))
           ->add('body', TextareaType::class, array(
               'label' => 'body',
               'translation_domain' => 'FOSMessageBundle',
           ));
       }
   
       public function configureOptions(OptionsResolver $resolver)
       {
           $resolver->setDefaults(array(
               'intention' => 'message',
           ));
       }
   
       /**
        * {@inheritdoc}
        */
       public function getBlockPrefix()
       {
           return 'new_thread_message';
       }
   }
   

5. Create a UsernameFormType form type class to handle transforming and displaying the username.

   class UsernameFormType extends AbstractType
   {
       /**
        * @var UserToUsernameTransformer
        */
       protected $usernameTransformer;
   
       /**
        * Constructor.
        *
        * @param UserToUsernameTransformer $usernameTransformer
        */
       public function __construct(UserToUsernameTransformer $usernameTransformer)
       {
           $this->usernameTransformer = $usernameTransformer;
       }
   
       /**
        * {@inheritdoc}
        */
       public function buildForm(FormBuilderInterface $builder, array $options)
       {
           $builder->addModelTransformer($this->usernameTransformer);
       }
   
       /**
        * {@inheritdoc}
        */
       public function getParent()
       {
           return TextType::class;
       }
   
       /**
        * {@inheritdoc}
        */
       public function getBlockPrefix()
       {
           return 'toolsets_username_type';
       }
   }
   

That should get it working.