cdn.basic.css.inc in CDN 7.2

Overrides of Drupal's CSS aggregation system. Ensures that files referenced by CSS files are also served from the CDN, according to the CDN module's CSS aggregation rules.

File

cdn.basic.css.inc

<?php

/**
 * @file
 * Overrides of Drupal's CSS aggregation system. Ensures that files referenced
 * by CSS files are also served from the CDN, according to the CDN module's
 * CSS aggregation rules.
 */

/**
 * Near-identical to @see drupal_aggregate_css().
 *
 * Changes: call _cdn_build_css_cache() instead of drupal_build_css_cache().
 */
function _cdn_aggregate_css(&$css_groups) {

  // Don't override Drupal core's aggregation if this page is not going to use
  // a CDN anyway.
  if (!cdn_check_protocol() && !cdn_check_drupal_path($_GET['q'])) {
    return;
  }
  $preprocess_css = variable_get('preprocess_css', FALSE) && (!defined('MAINTENANCE_MODE') || MAINTENANCE_MODE != 'update');

  // For each group that needs aggregation, aggregate its items.
  foreach ($css_groups as $key => $group) {
    switch ($group['type']) {

      // If a file group can be aggregated into a single file, do so, and set
      // the group's data property to the file path of the aggregate file.
      case 'file':
        if ($preprocess_css) {
          if ($group['preprocess']) {
            $css_groups[$key]['data'] = _cdn_build_css_cache($group['items']);
          }
          else {
            $suffix = '';
            if (count($group['items']) == 1) {
              $suffix .= '_' . basename($group['items'][0]['data']);
            }
            $css_groups[$key]['data'] = _cdn_build_css_cache($group['items'], $suffix);
          }
        }
        break;

      // Aggregate all inline CSS content into the group's data property.
      case 'inline':
        $css_groups[$key]['data'] = '';
        foreach ($group['items'] as $item) {
          $css_groups[$key]['data'] .= drupal_load_stylesheet_content($item['data'], $item['preprocess']);
        }
        break;
    }
  }
}

/**
 * Near-identical to @see drupal_build_css_cache().
 *
 * Changes:
 * - the inner loop is modified
 * - uses _cdn_build_css_path() instead of drupal_build_css_path().
 */
function _cdn_build_css_cache($css, $suffix = '') {

  // Create different CSS aggregation maps for HTTP and HTTPS.
  $https_mapping = variable_get(CDN_BASIC_MAPPING_HTTPS_VARIABLE, '');
  $css_cache_var = cdn_request_is_https() ? 'cdn_css_cache_files_https' : 'cdn_css_cache_files_http';
  $data = '';
  $uri = '';
  $map = variable_get($css_cache_var, array());

  // Create a new array so that only the file names are used to create the hash.
  // This prevents new aggregates from being created unnecessarily.
  $css_data = array();
  foreach ($css as $css_file) {
    $css_data[] = $css_file['data'];
  }
  $key = hash('sha256', serialize($css_data));
  if (isset($map[$key])) {
    $uri = $map[$key];
  }
  if (empty($uri) || !file_exists($uri)) {

    // Build aggregate CSS file.
    foreach ($css as $stylesheet) {

      // Only 'file' stylesheets can be aggregated.
      if ($stylesheet['type'] == 'file') {
        $contents = drupal_load_stylesheet($stylesheet['data'], TRUE);

        // Get the parent directory of this file, relative to the Drupal root.
        $css_base_url = drupal_substr($stylesheet['data'], 0, strrpos($stylesheet['data'], '/'));
        _cdn_build_css_path(NULL, $css_base_url . '/');

        // Anchor all paths in the CSS with its base URL, ignoring external and absolute paths.
        $data .= preg_replace_callback('/url\\(\\s*[\'"]?(?![a-z]+:|\\/+)([^\'")]+)[\'"]?\\s*\\)/i', '_cdn_build_css_path', $contents);
      }
    }

    // Per the W3C specification at http://www.w3.org/TR/REC-CSS2/cascade.html#at-import,
    // @import rules must proceed any other style, so we move those to the top.
    $regexp = '/@import[^;]+;/i';
    preg_match_all($regexp, $data, $matches);
    $data = preg_replace($regexp, '', $data);
    $data = implode('', $matches[0]) . $data;

    // Prefix filename to prevent blocking by firewalls which reject files
    // starting with "ad*".
    $filename = 'css_' . drupal_hash_base64($data) . $suffix . '.css';

    // Create the css/ within the files folder.
    $csspath = $css_cache_var == 'cdn_css_cache_files_https' ? 'public://cdn/css/https' : 'public://cdn/css/http';
    $uri = $csspath . '/' . $filename;

    // Create the CSS file.
    file_prepare_directory($csspath, FILE_CREATE_DIRECTORY | FILE_MODIFY_PERMISSIONS);
    if (!file_exists($uri) && !file_unmanaged_save_data($data, $uri, FILE_EXISTS_REPLACE)) {
      return FALSE;
    }

    // If CSS gzip compression is enabled, clean URLs are enabled (which means
    // that rewrite rules are working) 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.
    if (variable_get('css_gzip_compression', TRUE) && variable_get('clean_url', 0) && extension_loaded('zlib')) {
      if (!file_exists($uri . '.gz') && !file_unmanaged_save_data(gzencode($data, 9, FORCE_GZIP), $uri . '.gz', FILE_EXISTS_REPLACE)) {
        return FALSE;
      }
    }

    // Save the updated map.
    $map[$key] = $uri;
    variable_set($css_cache_var, $map);
  }
  return $uri;
}

/**
 * Near-identical to @see _drupal_build_css_path().
 *
 * Changes: apply file_create_url() to every file!
 */
function _cdn_build_css_path($matches, $base = NULL) {
  $_base =& drupal_static(__FUNCTION__);

  // Store base path for preg_replace_callback.
  if (isset($base)) {
    $_base = $base;
  }

  // Prefix with base and remove '../' segments where possible.
  $url = $_base . $matches[1];
  $last = '';
  while ($url != $last) {
    $last = $url;
    $url = preg_replace('`(^|/)(?!\\.\\./)([^/]+)/\\.\\./`', '$1', $url);
  }
  $parsed_url = parse_url($url);
  $base_url = isset($parsed_url['scheme']) ? $parsed_url['scheme'] . '://' : '';
  $base_url .= isset($parsed_url['user']) ? $parsed_url['user'] : '';
  $base_url .= isset($parsed_url['pass']) ? ':' . $parsed_url['pass'] : '';
  if (isset($parsed_url['user']) || isset($parsed_url['pass'])) {
    $base_url .= '@';
  }
  $base_url .= isset($parsed_url['host']) ? $parsed_url['host'] : '';
  $base_url .= isset($parsed_url['port']) ? ':' . $parsed_url['port'] : '';
  $base_url .= isset($parsed_url['path']) ? $parsed_url['path'] : '';
  $query = isset($parsed_url['query']) ? $parsed_url['query'] : '';

  // In the case of certain URLs, we may have simply a '?' character without
  // further parameters. parse_url() misses this and leaves 'query' blank, so
  // need to this back in.
  // See http://www.fontspring.com/blog/the-new-bulletproof-font-face-syntax
  // for more information.
  if ($query != '' || strpos($url, $base_url . '?') === 0) {
    $query = '?' . $query;
  }
  $fragment = isset($parsed_url['fragment']) ? '#' . $parsed_url['fragment'] : '';
  return 'url(' . file_create_url($base_url) . $query . $fragment . ')';
}

Functions

Name	Description
_cdn_aggregate_css	Near-identical to Changes: call _cdn_build_css_cache() instead of drupal_build_css_cache().
_cdn_build_css_cache	Near-identical to Changes:
_cdn_build_css_path	Near-identical to Changes: apply file_create_url() to every file!