Leverage file entity metadata for failed/dead oEmbed requests

One of the hidden features of oEmbed is that when file entity module is enabled, the original oEmbed response is stored in the file entity's metadata attribute.

The intent was to capture a valid oEmbed response that could be used later if the original content disappeared or the endpoint was unavailable. It's pretty common that an oEmbed endpoint will be unavailable or has usage limits. If a bad response is returned, this may be cached and a faulty bit of embedded content is displayed (or not displayed).

Here's code that I wrote that leverages the original response that is stored in file entity metadata. It proxies all oEmbed provider plugin callbacks so that if they return nothing, the file entity can be checked as a last resort.

I don't really know if this code should be part of oEmbed module or if this is even good, so I am posting it here for your feedback and use.

/**
 * Implements hook_ctools_plugin_post_alter().
 */
function oembedlastresort_ctools_plugin_post_alter(&$plugin, &$info) {
  if ($info['module'] === 'oembed' && $info['type'] === 'providers') {
    $plugin['proxy callback'] = $plugin['callback'];
    $plugin['callback'] = 'oembedlastresort_provider_callback';
  }
}

/**
 * Proxy callback loads oembed response from file metadata.
 *
 * @param $plugin
 * @param $url
 * @param $matches
 * @param $parameters
 * @return mixed
 */
function oembedlastresort_provider_callback($plugin, $url, $matches, $parameters) {
  $function = $plugin['proxy callback'];
  if ($function) {
    $embed = call_user_func($function, $plugin, $url, $matches, $parameters);
  }

  if (!$embed) {
    $uri = 'oembed://'. drupal_encode_path($url);
    $files = entity_load('file', FALSE, array('uri' => $uri));
    $file = !empty($files) ? reset($files) : FALSE;
    if ($file && isset($file->metadata['oembed'])) {
      $embed = $file->metadata['oembed'];
    }
  }
  return $embed;
}