function editor_file_download

Implements hook_file_download().

See also

file_file_download()

file_get_file_references()

File

core/modules/editor/editor.module, line 493

Code

function editor_file_download($uri) {
    // Get the file record based on the URI. If not in the database just return.
    
    /** @var \Drupal\file\FileRepositoryInterface $file_repository */
    $file_repository = \Drupal::service('file.repository');
    $file = $file_repository->loadByUri($uri);
    if (!$file) {
        return;
    }
    // Temporary files are handled by file_file_download(), so nothing to do here
    // about them.
    // @see file_file_download()
    // Find out if any editor-backed field contains the file.
    $usage_list = \Drupal::service('file.usage')->listUsage($file);
    // Stop processing if there are no references in order to avoid returning
    // headers for files controlled by other modules. Make an exception for
    // temporary files where the host entity has not yet been saved (for example,
    // an image preview on a node creation form) in which case, allow download by
    // the file's owner.
    if (empty($usage_list['editor']) && ($file->isPermanent() || $file->getOwnerId() != \Drupal::currentUser()->id())) {
        return;
    }
    // Editor.module MUST NOT call $file->access() here (like file_file_download()
    // does) as checking the 'download' access to a file entity would end up in
    // FileAccessControlHandler->checkAccess() and ->getFileReferences(), which
    // calls file_get_file_references(). This latter one would allow downloading
    // files only handled by the file.module, which is exactly not the case right
    // here. So instead we must check if the current user is allowed to view any
    // of the entities that reference the image using the 'editor' module.
    if ($file->isPermanent()) {
        $referencing_entity_is_accessible = FALSE;
        $references = empty($usage_list['editor']) ? [] : $usage_list['editor'];
        foreach ($references as $entity_type => $entity_ids_usage_count) {
            $referencing_entities = \Drupal::entityTypeManager()->getStorage($entity_type)
                ->loadMultiple(array_keys($entity_ids_usage_count));
            
            /** @var \Drupal\Core\Entity\EntityInterface $referencing_entity */
            foreach ($referencing_entities as $referencing_entity) {
                if ($referencing_entity->access('view', NULL, TRUE)
                    ->isAllowed()) {
                    $referencing_entity_is_accessible = TRUE;
                    break 2;
                }
            }
        }
        if (!$referencing_entity_is_accessible) {
            return -1;
        }
    }
    // Access is granted.
    $headers = file_get_content_headers($file);
    return $headers;
}