Swoole\Upload::getFileExt PHP Méthode

    public static function getFileExt($file)
    {
        $s = strrchr($file, '.');
        if ($s === false) {
            return false;
        }
        return strtolower(trim(substr($s, 1)));
    }

 /**
  * 静态请求
  * @param $request
  * @param $response
  * @return unknown_type
  */
 function processStatic($request, Swoole\Response $response)
 {
     $path = $this->document_root . '/' . $request->meta['path'];
     if (is_file($path)) {
         $read_file = true;
         if ($this->expire) {
             $expire = intval($this->config['server']['expire_time']);
             $fstat = stat($path);
             //过期控制信息
             if (isset($request->head['If-Modified-Since'])) {
                 $lastModifiedSince = strtotime($request->head['If-Modified-Since']);
                 if ($lastModifiedSince and $fstat['mtime'] <= $lastModifiedSince) {
                     //不需要读文件了
                     $read_file = false;
                     $response->setHttpStatus(304);
                 }
             } else {
                 $response->head['Cache-Control'] = "max-age={$expire}";
                 $response->head['Pragma'] = "max-age={$expire}";
                 $response->head['Last-Modified'] = date(self::DATE_FORMAT_HTTP, $fstat['mtime']);
                 $response->head['Expires'] = "max-age={$expire}";
             }
         }
         $ext_name = Swoole\Upload::getFileExt($request->meta['path']);
         if ($read_file) {
             $response->head['Content-Type'] = $this->mime_types[$ext_name];
             $response->body = file_get_contents($path);
         }
         return true;
     } else {
         return false;
     }
 }