public function copy($from_bucket, $from_key, $to_bucket, $to_key, $force = false)
{
$from = \Qiniu\entry($from_bucket, $from_key);
$to = \Qiniu\entry($to_bucket, $to_key);
$path = '/copy/' . $from . '/' . $to;
if ($force) {
$path .= '/force/true';
}
list(, $error) = $this->rsPost($path);
return $error;
}