- Patch #561858 by effulgentsia, sun, rfay, Nick_vh, merlinofchaos, katbailey, dereine, tstoeckler: drupal_add_js() and drupal_add_css() to work for AJAX requests too by adding lazy-load to AJAX framework.

1 files changed, 92 insertions, 4 deletions

diff --git a/includes/ajax.inc b/includes/ajax.inc
index 2c987f035..bd590aa66 100644
--- a/includes/ajax.inc
+++ b/includes/ajax.inc
@@ -213,11 +213,66 @@
  *   functions.
  */
 function ajax_render($commands = array()) {
-  // Automatically extract any 'settings' added via drupal_add_js() and make
-  // them the first command.
-  $scripts = drupal_add_js(NULL, NULL);
+  // 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]);
+    }
+  }
+
+  // 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'])) {
-    array_unshift($commands, ajax_command_settings(call_user_func_array('array_merge_recursive', $scripts['settings']['data'])));
+    $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.
@@ -307,6 +362,39 @@ function ajax_form_callback() {
 }
 
 /**
+ * Theme callback for AJAX requests.
+ *
+ * Many different pages can invoke an AJAX request to system/ajax or another
+ * generic AJAX path. It is almost always desired for an AJAX response to be
+ * rendered using the same theme as the base page, because most themes are built
+ * with the assumption that they control the entire page, so if the CSS for two
+ * themes are both loaded for a given page, they may conflict with each other.
+ * For example, Bartik is Drupal's default theme, and Seven is Drupal's default
+ * administration theme. Depending on whether the "Use the administration theme
+ * when editing or creating content" checkbox is checked, the node edit form may
+ * be displayed in either theme, but the AJAX response to the Field module's
+ * "Add another item" button should be rendered using the same theme as the rest
+ * of the page. Therefore, system_menu() sets the 'theme callback' for
+ * 'system/ajax' to this function, and it is recommended that modules
+ * implementing other generic AJAX paths do the same.
+ */
+function ajax_base_page_theme() {
+  if (!empty($_POST['ajax_page_state']['theme']) && !empty($_POST['ajax_page_state']['theme_token'])) {
+    $theme = $_POST['ajax_page_state']['theme'];
+    $token = $_POST['ajax_page_state']['theme_token'];
+
+    // Prevent a request forgery from giving a person access to a theme they
+    // shouldn't be otherwise allowed to see. However, since everyone is allowed
+    // to see the default theme, token validation isn't required for that, and
+    // bypassing it allows most use-cases to work even when accessed from the
+    // page cache.
+    if ($theme === variable_get('theme_default', 'bartik') || drupal_valid_token($token, $theme)) {
+      return $theme;
+    }
+  }
+}
+
+/**
  * Package and send the result of a page callback to the browser as an AJAX response.
  *
  * @param $page_callback_result