How to resolve a File object from a Vich field

Assuming you have a User entity with a photo property that’s a Vich field (i.e., contains the VichUploadable attribute), you can do something like this:

<?php 

$this->vichService->resolveFile($user, 'photo');

Where the VichService::resolveFile() method has the following implementation:

<?php

declare(strict_types=1);

namespace App\Service;

use Symfony\Component\HttpFoundation\File\File;
use Vich\UploaderBundle\Storage\StorageInterface;

readonly class VichService
{
    public function __construct(private StorageInterface $storage)
    {
    }

    /**
     * Resolve a File object from the specified object and mapping name.
     */
    public function resolveFile(object $object, string $fieldName): File
    {
        if (!property_exists($object, $fieldName)) {
            throw new \LogicException(sprintf("The object %s has no property '%s'", get_class($object), $fieldName));
        }

        $stream       = $this->storage->resolveStream($object, $fieldName);
        $tempFilePath = tempnam(sys_get_temp_dir(), get_class($object) . '_');

        file_put_contents($tempFilePath, $stream);

        return new File($tempFilePath);
    }
}