readmedia.php for Joomla 4 and 5

readmedia.php

<?php
/**
 * @copyright  Copyright (C) 2018 David Jardin - djumla GmbH
 * @package    Readmedia
 * @version    1.0.0
 * @license    GNU GPLv3 <http://www.gnu.org/licenses/gpl.html>
 * @link       http://www.djumla.de
 *
 * 1.0.0-KRJE
 * - Updated version to support video streams in Safari (Webkit) - Viktor Vogel - https://www.kubik-rubik.de
 */

declare(strict_types=1);

use Joomla\CMS\Application\SiteApplication;
use Joomla\CMS\Factory;
use Joomla\CMS\Session\Session;
use Joomla\CMS\Uri\Uri;
use Joomla\Session\Session as SessionAlias;
use Joomla\Session\SessionInterface;

/* Initialize Joomla framework */
const _JEXEC = 1;

// Load system defines
if (file_exists(__DIR__ . '/defines.php')) {
    require_once __DIR__ . '/defines.php';
}

if (!defined('_JDEFINES')) {
    define('JPATH_BASE', __DIR__);
    require_once JPATH_BASE . '/includes/defines.php';
}

require_once JPATH_BASE . '/includes/framework.php';

/* Create the Application */
$container = Factory::getContainer();

$container->alias('session.web', 'session.web.site')
          ->alias('session', 'session.web.site')
          ->alias('JSession', 'session.web.site')
          ->alias(Session::class, 'session.web.site')
          ->alias(SessionAlias::class, 'session.web.site')
          ->alias(SessionInterface::class, 'session.web.site');

// Instantiate the application.
$app = $container->get(SiteApplication::class);

// Load the extension Namespaces
JLoader::register('JNamespacePsr4Map', JPATH_LIBRARIES . '/namespacemap.php');
$extensionPsr4Loader = new JNamespacePsr4Map();
$extensionPsr4Loader->load();

// Set the application as global app
Factory::$application = $app;

// Actual permission check starts here
if (!Factory::getApplication()->getSession()->get('user')->id) {
    header('HTTP/1.0 403 access denied');

    exit('Access denied');
}

$requestedFile = urldecode(str_replace(Uri::root(), '', Uri::current()));
$location = __DIR__ . '/' . $requestedFile;

if (!file_exists($location)) {
    header('HTTP/1.0 404 file not found');

    exit('File not found');
}

$size = filesize($location);
$time = date('r', filemtime($location));
$fm = @fopen($location, 'rb');

if (!$fm) {
    header('HTTP/1.0 500 Internal Server Error');

    exit();
}

$start = 0;
$end = $size - 1;
$length = $size;

if ($_SERVER['HTTP_RANGE'] ?? null) {
    if (preg_match('/bytes=(\d+)-(\d*)/', $_SERVER['HTTP_RANGE'], $matches)) {
        $start = (int)$matches[1];

        if (($matches[2] ?? null) && is_numeric($matches[2])) {
            $end = (int)$matches[2];
        }

        $length = $end - $start + 1;

        header('HTTP/1.1 206 Partial Content');
        header("Content-Range: bytes $start-$end/$size");
    }
} else {
    header('HTTP/1.1 200 OK');
}

header('Content-Type: ' . mime_content_type($location));
header('Accept-Ranges: bytes');
header('Content-Length: ' . $length);
header('Cache-Control: public, must-revalidate, max-age=0');
header('Pragma: no-cache');
header('Content-Disposition: inline; filename=' . basename($location));
header('Content-Transfer-Encoding: binary');
header("Last-Modified: $time");
header('Connection: close');

fseek($fm, $start);

$bufferSize = 1024 * 16;

while (!feof($fm) && ($pos = ftell($fm)) <= $end && connection_status() === CONNECTION_NORMAL) {
    if ($pos + $bufferSize > $end) {
        $bufferSize = $end - $pos + 1;
    }

    echo fread($fm, $bufferSize);
    flush();
}

fclose($fm);

Bei mir funktioniert es bei Joomla Ver 3.X sowie Joomla 5.x, nachdem ich aber mit verschiedenen Hoster arbeite, hat es anfänglich nicht gefunzt.
Der Grund war, dass es jeweils nginx Server waren, keine Apache, nginx verarbeitet offenbar kein .htaccess und findet deswegen natürlich das Script nicht - also alles paletti, vielleicht sind diese Angaben für einige User interessant
Stefan