Modulo di servizio CDN semplice realizzato in PHP

Ho usato CloudFlare per ridurre il carico del traffico, ma ho constatato che la connessione era molto lenta perché il punto di connessione era LAX (Los Angeles), così ho creato in fretta questo modulo per usarlo come CDN.

Il server si trova a Tokyo (Vultr).

Il principio è quello di reindirizzare kilho.net/{file} a cdn.kilho.net/{file}, distribuendo così il traffico dell’hosting principale.

[PHP]

<?
$cfg[‘url’] = ‘kilho.net’;
$cfg[‘cache’] = ‘../data/cache’;

$url = $_SERVER[‘REQUEST_SCHEME’].’://’.$cfg[‘url’].$_SERVER[‘REQUEST_URI’];
$url_arr = parse_url($url);

switch($_SERVER[‘REQUEST_METHOD’])
{
case ‘GET’:
$filename = $cfg[‘cache’].$url_arr[‘path’];
$dirname = dirname($filename);
if(!is_file($filename))
{
if(!is_dir($dirname)) mkdir($dirname, 0707, true);

$ch = curl_init();
$fp = fopen($filename, ‘w’);
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_REFERER, $_SERVER[‘REQUEST_SCHEME’].’://’.$cfg[‘url’]);
curl_setopt($ch, CURLOPT_FILE, $fp);
curl_exec($ch);
fclose($fp);

switch($code = curl_getinfo($ch, CURLINFO_HTTP_CODE))
{
case 200:
break;

default:
touch($filename, $code);
}
curl_close($ch);
}

if(is_file($filename))
{
$filetime = filemtime($filename);

if($filetime<1000)
{
header(‘HTTP/1.0 ‘.$filetime);
} else {
include ‘_mime.php’;
$filetype = get_mime($filename);
$lastmodified = filemtime($filename);
$etag = md5_file($filename);

header(‘Content-Type: ‘.$filetype);
header(‘Expires: ‘.gmdate(‘D, d M Y H:i:s’, time()+77760000).’ GMT’);
header(‘Cache-Control: public, max-age=77760000’);
header(‘Last-Modified: ‘.gmdate(‘D, d M Y H:i:s’, $lastmodified).’ GMT’);
header(‘Etag: ‘.$etag);
header(‘Access-Control-Allow-Origin: *’);

if(isset($_SERVER[‘HTTP_IF_MODIFIED_SINCE’]))
{
if($_SERVER[‘HTTP_IF_MODIFIED_SINCE’]==gmdate(‘D, d M Y H:i:s’, $lastmodified).’ GMT’||$_SERVER[‘HTTP_IF_NONE_MATCH’]==$etag)
{
header(‘HTTP/1.0 304 Not Modified’);
exit;
}
}
}

if(strstr($_SERVER[‘HTTP_ACCEPT_ENCODING’], ‘gzip’))
if(in_array($filetype, array(‘text/plain’, ‘text/html’, ‘text/css’, ‘text/javascript’, ‘application/json’, ‘application/xml’)))
ob_start(‘ob_gzhandler’);

$fp = fopen($filename, ‘rb’);
fpassthru($fp);
fclose ($fp);

exit;
}

break;

case ‘POST’:

case ‘PUT’:

case ‘DELETE’;
break;
}

header(‘HTTP/1.0 404 File Not Found.’);
?>

[/PHP]