PHP

php download rate limit

<?php

$file_to_download = '1.mp3';
$client_file = '1.mp3';

$download_rate = 10; // 200Kb/s

$f = null;

try {
	if (!file_exists($file_to_download)) {
		throw new Exception('File ' . $file_to_download . ' does not exist');
	}

	if (!is_file($file_to_download)) {
		throw new Exception('File ' . $file_to_download . ' is not valid');
	}

	header('Cache-control: private');
	header('Content-Type: application/octet-stream');
	header('Content-Length: ' . filesize($file_to_download));
	header('Content-Disposition: filename=' . $client_file);

	// flush the content to the web browser
	flush();

	$f = fopen($file_to_download, 'r');

	while (!feof($f)) {
		// send the file part to the web browser
		print fread($f, round($download_rate * 1024));

		// flush the content to the web browser
		flush();

		// sleep one second
		sleep(1);
	}
} catch (Throwable $e) {
	echo $e->getMessage();
} finally {
	if ($f) {
		fclose($f);
	}
}