Easy Image upload with Symfony 4

FileUploader.php

<?php
/**
 * Created by PhpStorm.
 * User: ciryk
 * Date: 11/07/18
 * Time: 19:23
 */

namespace App\Service;


use Symfony\Component\HttpFoundation\File\UploadedFile;

class FileUploader
{
    private $targetDirectory;

    /**
     * FileUploader constructor.
     * @param $targetDirectory
     */
    public function __construct($targetDirectory)
    {
        $this->targetDirectory = $targetDirectory;
    }

    public function upload(UploadedFile $file)
    {
        $filename = md5(uniqid()) . '.' . $file->guessExtension();
        $file->move($this->targetDirectory, $filename);
        return $filename;
    }
}

Image.php

<?php
/**
 * Created by PhpStorm.
 * User: ciryk
 * Date: 11/07/18
 * Time: 18:56
 */

namespace App\Entity;


use Doctrine\ORM\Mapping as ORM;
use Symfony\Component\Validator\Constraints as Assert;

/**
 * @ORM\Entity
 * @ORM\Table(name="image")
 */
class Image
{
    /**
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="AUTO")
     * @ORM\Column(type="integer")
     */
    private $id;

    /**
     * @var string $file
     * @ORM\Column(type="string")
     *
     * @Assert\NotBlank(message="Please, upload an image first.")
     * @Assert\File(mimeTypes={ "image/png", "image/jpeg", "image/jpg" })
     */
    private $file;

    /**
     * @ORM\Column(type="string", nullable=true)
     */
    private $alt;

    /**
     * @return mixed
     */
    public function getId()
    {
        return $this->id;
    }

    /**
     * @param mixed $id
     */
    public function setId($id): void
    {
        $this->id = $id;
    }

    /**
     * @return string
     */
    public function getFile()
    {
        return $this->file;
    }

    /**
     * @param string $file
     */
    public function setFile($file)
    {
        if ($file) {
            $this->file = $file;
        }
    }

    /**
     * @return mixed
     */
    public function getAlt()
    {
        return $this->alt;
    }

    /**
     * @param mixed $alt
     */
    public function setAlt($alt)
    {
        $this->alt = $alt;
    }
}

ImageType.php

<?php
/**
 * Created by PhpStorm.
 * User: ciryk
 * Date: 9/12/18
 * Time: 21:27
 */

namespace App\Form;
use App\Entity\Image;
use Symfony\Component\Form\CallbackTransformer;
use Symfony\Component\Form\Extension\Core\Type\FileType;
use Symfony\Component\Form\FormBuilderInterface;
use Symfony\Component\HttpFoundation\File\File;
use Symfony\Component\HttpFoundation\File\UploadedFile;
use Symfony\Component\OptionsResolver\OptionsResolver;

class ImageType extends FileType
{
    private $imagePath;
    /**
     * ImageType constructor.
     * @param $imagePath
     */
    public function __construct($imagePath)
    {
        $this->imagePath = $imagePath;
    }

    public function buildForm(FormBuilderInterface $builder, array $options)
    {
        parent::buildForm($builder, $options);
        $builder->addModelTransformer(new CallbackTransformer(
            function(Image $image = null) {
                if ($image instanceof Image) {
                    return new File($this->imagePath . $image->getFile());
                }
            },
            function(UploadedFile $uploadedFile = null) {
                if ($uploadedFile instanceof UploadedFile) {
                    $image = new Image();
                    $image->setFile($uploadedFile);
                    return $image;
                }
            }
        ));
    }

    public function getBlockPrefix()
    {
        return 'image';
    }

    public function configureOptions(OptionsResolver $resolver)
    {
        parent::configureOptions($resolver);
        $resolver->setDefaults([
            'required' => false
        ]);
    }
}

ImageUploadListener.php

<?php
/**
 * Created by PhpStorm.
 * User: ciryk
 * Date: 9/12/18
 * Time: 21:28
 */

namespace App\EventListener;
use App\Entity\Image;
use App\Service\FileUploader;
use Doctrine\ORM\Event\LifecycleEventArgs;
use Doctrine\ORM\Event\PreUpdateEventArgs;
use Symfony\Component\HttpFoundation\File\UploadedFile;

class ImageUploadListener
{
    private $uploader;
    /**
     * ImageUploadListener constructor.
     * @param $uploader
     */
    public function __construct(FileUploader $uploader)
    {
        $this->uploader = $uploader;
    }
    public function prePersist(LifecycleEventArgs $args)
    {
        $entity = $args->getEntity();
        $this->uploadFile($entity);
    }
    public function preUpdate(PreUpdateEventArgs $args)
    {
        $entity = $args->getEntity();
        $this->uploadFile($entity);
    }
    private function uploadFile($entity)
    {
        if (!$entity instanceof Image) {
            return;
        }
        $file = $entity->getFile();
        if ($file instanceof UploadedFile) {
            $filename = $this->uploader->upload($file);
            $entity->setFile($filename);
        }
    }
}

please
how to autowiring arg $imagePath

please
how to autowiring arg $imagePath

Hi @carteur007 You will need to add this as a service. F.e. in config/services.yaml add the following:

App\Form\ImageType:
  arguments:
    - '%kernel.project_dir%/public/uploads/'

This will turn your form type class into a service, you can inject other services inside your constructor or you can add simple strings like above, the %kernel.project_dir% points to the root of you application.

This should work, if you have any problems let me know.