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function advagg_get_js in Advanced CSS/JS Aggregation 7

Same name and namespace in other branches
  1. 7.2 advagg.module \advagg_get_js()

Returns a themed presentation of all JavaScript code for the current page.

References to JavaScript files are placed in a certain order: first, all 'core' files, then all 'module' and finally all 'theme' JavaScript files are added to the page. Then, all settings are output, followed by 'inline' JavaScript code. If running update.php, all preprocessing is disabled.

Parameters

$scope: (optional) The scope for which the JavaScript rules should be returned. Defaults to 'header'.

$javascript: (optional) An array with all JavaScript code. Defaults to the default JavaScript array for the given scope.

Return value

All JavaScript code segments and includes for the scope as HTML tags.

File

./advagg.module, line 429
Advanced CSS/JS aggregation module

Code

function advagg_get_js($scope, $javascript) {

  // Filter out elements of the given scope.
  $items = array();
  foreach ($javascript as $key => $item) {
    if ($item['scope'] == $scope) {
      $items[$key] = $item;
    }
  }
  $output = '';

  // The index counter is used to keep aggregated and non-aggregated files in
  // order by weight.
  $index = 1;
  $processed = array();
  $files = array();
  $preprocess_js = variable_get('preprocess_js', FALSE) && (!defined('MAINTENANCE_MODE') || MAINTENANCE_MODE != 'update');

  // A dummy query-string is added to filenames, to gain control over
  // browser-caching. The string changes on every update or full cache
  // flush, forcing browsers to load a new copy of the files, as the
  // URL changed. Files that should not be cached (see drupal_add_js())
  // get REQUEST_TIME as query-string instead, to enforce reload on every
  // page request.
  $default_query_string = variable_get('css_js_query_string', '0');

  // For inline JavaScript to validate as XHTML, all JavaScript containing
  // XHTML needs to be wrapped in CDATA. To make that backwards compatible
  // with HTML 4, we need to comment out the CDATA-tag.
  $embed_prefix = "\n<!--//--><![CDATA[//><!--\n";
  $embed_suffix = "\n//--><!]]>\n";

  // Since JavaScript may look for arguments in the URL and act on them, some
  // third-party code might require the use of a different query string.
  $js_version_string = variable_get('drupal_js_version_query_string', 'v=');

  // Sort the JavaScript so that it appears in the correct order.
  uasort($items, 'drupal_sort_css_js');

  // Provide the page with information about the individual JavaScript files
  // used, information not otherwise available when aggregation is enabled.
  $setting['ajaxPageState']['js'] = array_fill_keys(array_keys($items), 1);
  unset($setting['ajaxPageState']['js']['settings']);
  drupal_add_js($setting, 'setting');

  // If we're outputting the header scope, then this might be the final time
  // that drupal_get_js() is running, so add the setting to this output as well
  // as to the drupal_add_js() cache. If $items['settings'] doesn't exist, it's
  // because drupal_get_js() was intentionally passed a $javascript argument
  // stripped off settings, potentially in order to override how settings get
  // output, so in this case, do not add the setting to this output.
  if ($scope == 'header' && isset($items['settings'])) {
    $items['settings']['data'][] = $setting;
  }

  // Loop through the JavaScript to construct the rendered output.
  $element = array(
    '#tag' => 'script',
    '#value' => '',
    '#attributes' => array(
      'type' => 'text/javascript',
    ),
  );
  foreach ($items as $item) {
    $query_string = empty($item['version']) ? $default_query_string : $js_version_string . $item['version'];
    switch ($item['type']) {
      case 'setting':
        $js_element = $element;
        $js_element['#value_prefix'] = $embed_prefix;
        $js_element['#value'] = 'jQuery.extend(Drupal.settings, ' . drupal_json_encode(drupal_array_merge_deep_array($item['data'])) . ");";
        $js_element['#value_suffix'] = $embed_suffix;
        $output .= theme('html_tag', array(
          'element' => $js_element,
        ));
        break;
      case 'inline':
        $js_element = $element;
        if ($item['defer']) {
          $js_element['#attributes']['defer'] = 'defer';
        }
        $js_element['#value_prefix'] = $embed_prefix;
        $js_element['#value'] = $item['data'];
        $js_element['#value_suffix'] = $embed_suffix;
        $processed[$index++] = theme('html_tag', array(
          'element' => $js_element,
        ));
        break;
      case 'file':
        $js_element = $element;
        if (!$item['preprocess'] || !$preprocess_js) {
          if ($item['defer']) {
            $js_element['#attributes']['defer'] = 'defer';
          }
          $query_string_separator = strpos($item['data'], '?') !== FALSE ? '&' : '?';
          $js_element['#attributes']['src'] = file_create_url($item['data']) . $query_string_separator . ($item['cache'] ? $query_string : REQUEST_TIME);
          $processed[$index++] = theme('html_tag', array(
            'element' => $js_element,
          ));
        }
        else {

          // By increasing the index for each aggregated file, we maintain
          // the relative ordering of JS by weight. We also set the key such
          // that groups are split by items sharing the same 'group' value and
          // 'every_page' flag. While this potentially results in more aggregate
          // files, it helps make each one more reusable across a site visit,
          // leading to better front-end performance of a website as a whole.
          // See drupal_add_js() for details.
          $key = 'aggregate_' . $item['group'] . '_' . $item['every_page'] . '_' . $index;
          $processed[$key] = '';
          $files[$key][$item['data']] = $item;
        }
        break;
      case 'external':
        $js_element = $element;

        // Preprocessing for external JavaScript files is ignored.
        if ($item['defer']) {
          $js_element['#attributes']['defer'] = 'defer';
        }
        $js_element['#attributes']['src'] = $item['data'];
        $processed[$index++] = theme('html_tag', array(
          'element' => $js_element,
        ));
        break;
    }
  }

  // Aggregate any remaining JS files that haven't already been output.
  if ($preprocess_js && count($files) > 0) {
    foreach ($files as $key => $file_set) {
      $uri = drupal_build_js_cache($file_set);

      // Only include the file if was written successfully. Errors are logged
      // using watchdog.
      if ($uri) {
        $preprocess_file = file_create_url($uri);
        $js_element = $element;
        $js_element['#attributes']['src'] = $preprocess_file;
        $processed[$key] = theme('html_tag', array(
          'element' => $js_element,
        ));
      }
    }
  }

  // Keep the order of JS files consistent as some are preprocessed and others are not.
  // Make sure any inline or JS setting variables appear last after libraries have loaded.
  return implode('', $processed) . $output;
}