Symfony3 wont convert file to UploadedFile - php

Question

I'm following this tutorial http://symfony.com/doc/current/controller/upload_file.html but the $file isn't being converted to an UploadedFile, it stays as a string:
var_dump($file);
/home/owner/Desktop/Workspace/Documentary/src/DW/DocumentaryBundle/Controller/Admin/DocumentaryController.php:103:string '/tmp/phpmmv1LP' (length=14)
Type error: Argument 1 passed to DW\DocumentaryBundle\Uploader\PosterUploader::upload() must be an instance of Symfony\Component\HttpFoundation\File\UploadedFile, string given, called in /home/owner/Desktop/Workspace/DocumentaryWIRE/src/DW/DocumentaryBundle/Controller/Admin/DocumentaryController.php on line 106
Create Action:
/**
* #param Request $request
* #return Response
*/
public function createAction(Request $request)
{
$documentary = new Documentary();
$form = $this->createForm(DocumentaryType::class, $documentary);
$form->handleRequest($request);
if ($form->isSubmitted() && $form->isValid()) {
$file = $documentary->getPoster();
$posterUploader = $this->getPosterUploader();
$fileName = $posterUploader->upload($file);
$documentary->setPoster($fileName);
$documentaryService = $this->getDocumentaryService();
$documentaryService->save($documentary);
}
return $this->render('DocumentaryBundle:Admin:create.html.twig', array(
'form' => $form->createView(),
));
}
View
{{ form_start(form) }}
{{ form_widget(form) }}
{{ form_end(form) }}
Form:
<?php
namespace DW\DocumentaryBundle\Form;
use DW\DocumentaryBundle\Entity\Documentary;
use Symfony\Bridge\Doctrine\Form\Type\EntityType;
use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\Extension\Core\Type\FileType;
use Symfony\Component\Form\Extension\Core\Type\IntegerType;
use Symfony\Component\Form\Extension\Core\Type\SubmitType;
use Symfony\Component\Form\Extension\Core\Type\TextareaType;
use Symfony\Component\Form\Extension\Core\Type\TextType;
use Symfony\Component\Form\FormBuilderInterface;
use Symfony\Component\OptionsResolver\OptionsResolver;
class DocumentaryType extends AbstractType
{
/**
* #param FormBuilderInterface $builder
* #param array $options
*/
public function buildForm(FormBuilderInterface $builder, array $options)
{
$builder
->add('title', TextType::class)
->add('storyline', TextareaType::class)
->add('summary', TextareaType::class)
->add('year', IntegerType::class)
->add('length', IntegerType::class)
->add('status', TextType::class)
->add('views', IntegerType::class)
->add('shortUrl', TextType::class)
->add('videoId', TextType::class)
->add('videoSource', TextType::class)
->add('poster', FileType::class, [
'label' => 'Poster'])
->add('category', EntityType::class, [
'class' => 'CategoryBundle:Category',
'choice_label' => 'name',
])
->add('submit', SubmitType::class);
}
/**
* #param OptionsResolver $resolver
*/
public function configureOptions(OptionsResolver $resolver)
{
$resolver->setDefaults(array(
'data_class' => Documentary::class,
));
}
/**
* #return string
*/
public function getName()
{
return "documentary";
}
}
Controller:
<?php
namespace DW\DocumentaryBundle\Uploader;
use Symfony\Component\HttpFoundation\File\UploadedFile;
class PosterUploader
{
/**
* #var string
*/
private $targetDir;
/**
* #param string $targetDir
*/
public function __construct(string $targetDir)
{
$this->targetDir = $targetDir;
}
/**
* #param UploadedFile $file
* #return string
*/
public function upload(UploadedFile $file)
{
$fileName = md5(uniqid()).'.'.$file->guessExtension();
$file->move($this->targetDir, $fileName);
return $fileName;
}
}

Answer 1

The documentation is NOT wrong! They don't use type hinting in their example:
// src/AppBundle/Entity/Product.php
public function setBrochure($brochure)
{
$this->brochure = $brochure;
return $this;
}
When you use string type hinting then UploadedFile::__toString() will be invoked!
So check your entity. It should be something like this:
public function setPoster($poster)
{
// ...
}

Answer 2

To get a file from request, in Symfony, you need to get $request->files. For example $request->files->get('file_name');.

Answer 3

The documentation is wrong, it should be: $file = $form->get('poster')->getData();
/**
* #param Request $request
* #return Response
*/
public function createAction(Request $request)
{
$documentary = new Documentary();
$form = $this->createForm(DocumentaryType::class, $documentary);
$form->handleRequest($request);
if ($form->isSubmitted() && $form->isValid()) {
$file = $form->get('poster')->getData();
$posterUploader = $this->getPosterUploader();
$fileName = $posterUploader->upload($file);
$documentary->setPoster($fileName);
$documentaryService = $this->getDocumentaryService();
$documentaryService->save($documentary);
}
return $this->render('DocumentaryBundle:Admin:create.html.twig', [
'form' => $form->createView(),
]);
}