function image_file_download

Implements hook_file_download().

Control the access to files underneath the styles directory.

File

core/modules/image/image.module, line 138

Exposes global functionality for creating image styles.

Code

function image_file_download($uri) {
  $path = StreamWrapperManager::getTarget($uri);

  // Private file access for image style derivatives.
  if (str_starts_with($path, 'styles/')) {
    $args = explode('/', $path);

    // Discard "styles", style name, and scheme from the path
    $args = array_slice($args, 3);

    // Then the remaining parts are the path to the image.
    $original_uri = StreamWrapperManager::getScheme($uri) . '://' . implode('/', $args);

    // Check that the file exists and is an image.
    $image = \Drupal::service('image.factory')
      ->get($uri);
    if ($image
      ->isValid()) {

      // If the image style converted the extension, it has been added to the
      // original file, resulting in filenames like image.png.jpeg. So to find
      // the actual source image, we remove the extension and check if that
      // image exists.
      if (!file_exists($original_uri)) {
        $converted_original_uri = ImageStyleDownloadController::getUriWithoutConvertedExtension($original_uri);
        if ($converted_original_uri !== $original_uri && file_exists($converted_original_uri)) {

          // The converted file does exist, use it as the source.
          $original_uri = $converted_original_uri;
        }
      }

      // Check the permissions of the original to grant access to this image.
      $headers = \Drupal::moduleHandler()
        ->invokeAll('file_download', [
        $original_uri,
      ]);

      // Confirm there's at least one module granting access and none denying access.
      if (!empty($headers) && !in_array(-1, $headers)) {
        return [
          // Send headers describing the image's size, and MIME-type.
          'Content-Type' => $image
            ->getMimeType(),
          'Content-Length' => $image
            ->getFileSize(),
        ];
      }
    }
    return -1;
  }

  // If it is the sample image we need to grant access.
  $samplePath = \Drupal::config('image.settings')
    ->get('preview_image');
  if ($path === $samplePath) {
    $image = \Drupal::service('image.factory')
      ->get($samplePath);
    return [
      // Send headers describing the image's size, and MIME-type.
      'Content-Type' => $image
        ->getMimeType(),
      'Content-Length' => $image
        ->getFileSize(),
    ];
  }
}