How can I add new components to a fieldset in webform 7.3.17?

Question

I'd like to customize the webform everytime the user saves a webform node. I'm using rules with a custom action that updates the webform when the user saves the node. Looking at devel, I haven't been able to figure out what the proper key to specify a parent fieldset is.

In my action I have the following:

for ($j = 1; $j <= 5; $j++) {
  $node->webform['components'][$i] = array(
    'nid' => $node->nid,
    'cid' => $i,
    'pid' => 0,
    'form_key' => "participant$j",
    'name' => "Participant",
    'type' => 'fieldset',
    'value' => '',
    'weight' => $j,
    'display' => array(
      'addmore' => $i,
    ),
    'extra' => array(
      'description' => 'Please provide the participant information listed below. Required items are denoted with an asterisk.',
      'title_display' => 0,
      'private' => 0,
      'collapsible' => 1,
      'conditional_component' => '',
      'conditional_operator' => '=',
      'conditional_values' => '',
    'mandatory' => 0,
    'page_num' => 1,
    ),
  );
  $i++;

  $node->webform['components'][$i] = array(
    'nid' => $node->nid,
    'cid' => $i,
    'pid' => 0,
    'form_key' => "first_name$j",
    'name' => 'First Name',
    'type' => 'textfield',
    'value' => '',

    'parent' => "participant$j",
    'extra' => array(
      'display' => array(
        'addmore' => $i,
      ),
      'title_display' => 'inline',
      'private' => 0,
      'disabled' => 0,
      'unique' => 0,
      'maxlength' => 60,
      'width' => '',
      'field_prefix' => '',
      'field_suffix' => '',
      'description' => '',
      'attributes' => array(),
      'conditional_component' => '',
      'conditional_operator' => '=',
      'conditional_values' => '',
    'mandatory' => 1,
    'page_num' => 1,
    ),
  );
  $i++;
...

Answer 1

It looks like setting the pid to the parent fieldset's cid achieves my goal.