AssetDumper::dump

public AssetDumper::dump($data, $file_extension)

public function dump($data, $file_extension) {
  // Prefix filename to prevent blocking by firewalls which reject files
  // starting with "ad*".
  $filename = $file_extension . '_' . Crypt::hashBase64($data) . '.' . $file_extension;
  // Create the css/ or js/ path within the files folder.
  $path = 'public://' . $file_extension;
  $uri = $path . '/' . $filename;
  // Create the CSS or JS file.
  file_prepare_directory($path, FILE_CREATE_DIRECTORY);
  if (!file_exists($uri) && !file_unmanaged_save_data($data, $uri, FILE_EXISTS_REPLACE)) {
    return FALSE;
  }
  // If CSS/JS gzip compression is enabled and the zlib extension is available
  // then create a gzipped version of this file. This file is served
  // conditionally to browsers that accept gzip using .htaccess rules.
  // It's possible that the rewrite rules in .htaccess aren't working on this
  // server, but there's no harm (other than the time spent generating the
  // file) in generating the file anyway. Sites on servers where rewrite rules
  // aren't working can set css.gzip to FALSE in order to skip
  // generating a file that won't be used.
  if (extension_loaded('zlib') && \Drupal::config('system.performance')->get($file_extension . '.gzip')) {
    if (!file_exists($uri . '.gz') && !file_unmanaged_save_data(gzencode($data, 9, FORCE_GZIP), $uri . '.gz', FILE_EXISTS_REPLACE)) {
      return FALSE;
    }
  }
  return $uri;
}