public function rename($file, $new_file)
{
$key = trim($file);
$url = "{$this->QINIU_RS_HOST}/move/" . self::qiniuEncode("{$this->bucket}:{$key}") . '/' . self::qiniuEncode("{$this->bucket}:{$new_file}");
trace($url);
$accessToken = $this->accessToken($url);
$response = $this->request($url, 'POST', ['Authorization' => "QBox {$accessToken}"]);
return $response;
}