Undefined index: private — _webform_client_form_rule_check()

Aye, the Private thing is new. Did this come up on an existing component on an existing form? I think it'll go away if you go into edit on the component and just save it again.

You'd need to go into edit and save each of the components individually to add the private key to their saved configurations in the database. I never thought of this as part of the upgrade path, but perhaps I should knock together an extra bit that will add this key to all existing components to prevent the notices on existing forms.

BTW, your production site should be configured to not show php notices and warnings - you should be reading these in your logs rather than on-screen.

I can't confirm this issue after upgrading an existing 7.x webform installation. Webform should prevent this error as long as all the component you're using have defined "private" => FALSE in their respective _webform_defaults_[component_name]() functions. As all the components that come with Webform include this, most likely the cause of this issue would be if you have a custom or add-on module that provides a component beyond the ones that Webform comes with. If so, you should contact the maintainer of that module and request that they add support for private/public component display.

To more accurately state that this shouldn't be necessary:

but perhaps I should knock together an extra bit that will add this key to all existing components to prevent the notices on existing forms.

The webform_component_defaults() function should already be providing all the defaults necessary, so an update hook is not needed. That's actually the exact reason that this function exists so we don't have to do update hooks or ugly !empty() or isset() checks all over the place. As you can see, it merges not only the top-level properties with defaults but also the "extra" properties:

function webform_component_defaults(&$component) {
  if ($defaults = webform_component_invoke($component['type'], 'defaults')) {
    foreach ($defaults as $key => $default) {
      if (!isset($component[$key])) {
        $component[$key] = $default;
      }
    }
    foreach ($defaults['extra'] as $extra => $default) {
      if (!isset($component['extra'][$extra])) {
        $component['extra'][$extra] = $default;
      }
    }
    $component['extra'] += array(
      'conditional_component' => '',
      'conditional_operator' => '=',
      'conditional_values' => '',
    );
  }
}

So all told I think that some component @the_phi is using is "non-standard" (not included with the core Webform project), and it just needs to be updated to set a default in its _webform_defaults_[component_name]() function.

Oh, and of course if you haven't tried already clearing your Drupal caches might also help, especially if you have the Entity Cache module enabled.

I'm fairly sure this has either been fixed or was a use-case specific issue. We haven't had any confirming reports.

(ps) path changed.