Export large files using Symfony StreamedResponse and prevent memory limit issues

MainController.php

<?php

namespace App\Controller;

use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;

class ExportController extends AbstractController
{
    /**
     * @Route("/export",name="export_route")
     */
    public function exportAction()
    {
        $handle = fopen('../my_large_file.csv', 'r');
        //$handle can also be read from php://temp if you need to create the file in the same action
        //in that case, do not forget to rewind($handle) after writing

        $callback = function () use ($handle) {
            fpassthru($handle);
            fclose($handle);
        };

        $response = new StreamedResponse($callback, 200);
        //set the headers to whatever you wish
        $response->headers->set('Content-Type', 'application/vnd.ms-excel');
        $response->headers->set('Content-Disposition', "attachment; filename=export.csv");
        return $response;
    }
}