Amazon S3 Force Download of Remote File with Symfony (AWS S3 PHP SDK V.3)

1. composer.json

{
    },
    "require": {
        "aws/aws-sdk-php": "3.*"
    }
}

2. parameters.yml

# This file is auto-generated during the composer install
parameters:
    ...
    amazon_key: my_key
    amazon_secret: my_secret
    amazon_bucket: my_bucket
    amazon_region: us-east-1
    amazon_version: latest

3. services.yml

services:
    ...
    my.amazon.s3:
        class: Aws\S3\S3Client
        factory_class: Aws\S3\S3Client
        factory_method: factory
        arguments:
            -
                credentials: { key: "%amazon_key%", secret: "%amazon_secret%" }
                region: "%amazon_region%"
                version: "%amazon_version%"

4. routing.yml

media_download:
  path: /media/download/{file}{trailingSlash}
  defaults:  { _controller: UtilBundle:Download, trailingSlash : "/" }
  requirements: { file: "([A-Za-z0-9-._s]+)", trailingSlash : "[/]{0,1}" }

5. index.html.twig

<a href="{{ url('media_download',{'file':entity.path}) }}">
  Download
</a>

6. DefaultController.php

<?php

namespace UtilBundle\Controller;

use Symfony\Bundle\FrameworkBundle\Controller\Controller;
use Symfony\Component\HttpFoundation\Response;

class DefaultController extends Controller
{
    public function downloadAction($file)
    {

        $file_path = "uploads/media/$file"; // path to file once inside bucket
        $s3 = $this->get('my.amazon.s3');

        $params = array(
            'Bucket'                     => $this->getParameter("amazon_bucket"),
            'Key'                        => $file_path,
            'ResponseContentType'        => 'application/octet-stream',
            'ResponseContentDisposition' => 'attachment; filename="'.$file.'"',
            'ResponseCacheControl'       => 'No-cache',
        );

        $command = $s3->getCommand('GetObject',$params);
        $preSignedRequest = $s3->createPresignedRequest($command, '+10 minutes');
        $body = $preSignedRequest->getUri();
        header("Location: ".$body);
        die();
        return new Response(); // controllers require a response or Symfony will error
    }
}

Hi, I tried and got the following error:

Service "app.amazon_s3" not found: even though it exists in the app's container, the container inside "App\Controller\AppController" is a smaller service locator that only knows about the "doctrine", "http_kernel", "parameter_bag", "request_stack", "router", "security.authorization_checker", "security.csrf.token_manager", "security.token_storage", "serializer", "session" and "twig" services. Try using dependency injection instead.

Eventually the solution proposed here worked: https://stackoverflow.com/questions/56326183/service-not-found-even-though-it-exists-in-the-apps-container