function hook_file_download

Control access to private file downloads and specify HTTP headers.

This hook allows modules enforce permissions on file downloads when the private file download method is selected. Modules can also provide headers to specify information like the file's name or MIME type.


$uri: The URI of the file.

Return value

If the user does not have permission to access the file, return -1. If the user has permission, return an array with the appropriate headers. If the file is not controlled by the current module, the return value should be NULL.

See also


Related topics

5 functions implement hook_file_download()

Note: this list is generated by pattern matching, so it may include some functions that are not actually implementations of this hook.

file_file_download in drupal/modules/file/file.module
Implements hook_file_download().
file_test_file_download in drupal/modules/simpletest/tests/file_test.module
Implements hook_file_download().
image_file_download in drupal/modules/image/image.module
Implements hook_file_download().
image_module_test_file_download in drupal/modules/image/tests/image_module_test.module
@file Provides Image module hook implementations for testing purposes.
user_file_download in drupal/modules/user/user.module
Implements hook_file_download().
2 invocations of hook_file_download()
file_download_headers in drupal/includes/
Retrieves headers for a private file download.
image_file_download in drupal/modules/image/image.module
Implements hook_file_download().


drupal/modules/system/system.api.php, line 3006
Hooks provided by Drupal core and the System module.


function hook_file_download($uri) {

  // Check if the file is controlled by the current module.
  if (!file_prepare_directory($uri)) {
    $uri = FALSE;
  if (strpos(file_uri_target($uri), variable_get('user_picture_path', 'pictures') . '/picture-') === 0) {
    if (!user_access('access user profiles')) {

      // Access to the file is denied.
      return -1;
    else {
      $info = image_get_info($uri);
      return array(
        'Content-Type' => $info['mime_type'],