php – 无法在drupal 7中添加图像字段

我能够创建一个简单的节点.但如果我将它与图像字段合并,它总是失败.

$file_path = drupal_realpath('tmp/test_image.jpg');
$file = (object) array(
    'uid' => 1,'uri' => $file_path,'filemime' => file_get_mimetype($file_path),'status' => 1,);
$copy = file_copy($file,'public://sites/default/files/field/image/testing/',FILE_EXISTS_RENAME);
$node->field_image[LANGUAGE_NONE][0] = (array) $copy;

它总是给我一个错误:(

The specified file could not be copied,because the destination directory is not properly configured. This may be caused by a problem with file or directory permissions. More information is available in the system log.