ajax_render

  1. drupal
    1. 8
    2. 7
Versions
7 – 8 ajax_render($commands = array())

Render a commands array into JSON.

Parameters

$commands A list of macro commands generated by the use of ajax_command_*() functions.

Related topics

▾ 1 function calls ajax_render()

ajax_deliver in includes/ajax.inc
Package and send the result of a page callback to the browser as an Ajax response.

Code

includes/ajax.inc, line 231

<?php
function ajax_render($commands = array()) {
  // Ajax responses aren't rendered with html.tpl.php, so we have to call
  // drupal_get_css() and drupal_get_js() here, in order to have new files added
  // during this request to be loaded by the page. We only want to send back
  // files that the page hasn't already loaded, so we implement simple diffing
  // logic using array_diff_key().
  foreach (array('css', 'js') as $type) {
    // It is highly suspicious if $_POST['ajax_page_state'][$type] is empty,
    // since the base page ought to have at least one JS file and one CSS file
    // loaded. It probably indicates an error, and rather than making the page
    // reload all of the files, instead we return no new files.
    if (empty($_POST['ajax_page_state'][$type])) {
      $items[$type] = array();
    }
    else {
      $function = 'drupal_add_' . $type;
      $items[$type] = $function();
      drupal_alter($type, $items[$type]);
      // @todo Inline CSS and JS items are indexed numerically. These can't be
//   reliably diffed with array_diff_key(), since the number can change
//   due to factors unrelated to the inline content, so for now, we strip
//   the inline items from Ajax responses, and can add support for them
//   when drupal_add_css() and drupal_add_js() are changed to using md5()
//   or some other hash of the inline content.
      foreach ($items[$type] as $key => $item) {
        if (is_numeric($key)) {
          unset($items[$type][$key]);
        }
      }
      // Ensure that the page doesn't reload what it already has.
      $items[$type] = array_diff_key($items[$type], $_POST['ajax_page_state'][$type]);
    }
  }

  // Settings are handled separately, later in this function, so that changes to
  // the ajaxPageState setting that occur during drupal_get_css() and
  // drupal_get_js() get included, and because the jQuery.extend() code produced
  // by drupal_get_js() for adding settings isn't appropriate during an Ajax
  // response, because it does not pass TRUE for the "deep" parameter, and
  // therefore, can clobber existing settings on the page.
  if (isset($items['js']['settings'])) {
    unset($items['js']['settings']);
  }

  // Render the HTML to load these files, and add Ajax commands to insert this
  // HTML in the page. We pass TRUE as the $skip_alter argument to prevent the
  // data from being altered again, as we already altered it above.
  $styles = drupal_get_css($items['css'], TRUE);
  $scripts_footer = drupal_get_js('footer', $items['js'], TRUE);
  $scripts_header = drupal_get_js('header', $items['js'], TRUE);

  $extra_commands = array();
  if (!empty($styles)) {
    $extra_commands[] = ajax_command_prepend('head', $styles);
  }
  if (!empty($scripts_header)) {
    $extra_commands[] = ajax_command_prepend('head', $scripts_header);
  }
  if (!empty($scripts_footer)) {
    $extra_commands[] = ajax_command_append('body', $scripts_footer);
  }
  if (!empty($extra_commands)) {
    $commands = array_merge($extra_commands, $commands);
  }

  $scripts = drupal_add_js();
  if (!empty($scripts['settings'])) {
    $settings = $scripts['settings'];
    // Automatically extract any settings added via drupal_add_js() and make
    // them the first command.
    array_unshift($commands, ajax_command_settings(call_user_func_array('array_merge_recursive', $settings['data']), TRUE));
  }

  // Allow modules to alter any Ajax response.
  drupal_alter('ajax_render', $commands);

  return drupal_json_encode($commands);
}
?>