Bulk update change author to siteowner

bulk_update_author.info

name = "Bulk update author"
description = "Bulk update the author of your nodes to siteowner."
package = "the AIM"
core = 7.x

bulk_update_author.module

<?php

/**
 * Implementation of hook_help().
 */
function bulk_update_author_help($path, $arg) {
 switch ($path) {
 case 'admin/help#bulk_update_author':
   $output = '<h3>' . t('Add extra bulk operation for content') . '</h3>';
   $output .= '<p>Unpublished node created by admin are not accessable for siteowners.<br />Therefore we must change the author of the nodes to siteowner. This module adds the extra bulk update action...</p>';
   $output .= '<ul>';
   $output .= '<li>Activate the <a href="/admin/modules">module</a></li>';
   $output .= '<li><a href="/admin/config/development/performance">Clear cache</a></li>';
   $output .= '<li>Bulk update your <a href="/admin/content">nodes</a></li>';
   $output .= '<li>Don\'t forget to desactivate the <a href="/admin/modules">module</a> when this magnificent piece of code did it\'s work</li>';
   $output .= '</ul>';
   $output .= '<p>Documentation of the hook: <a href="https://api.drupal.org/api/drupal/modules!node!node.api.php/function/hook_node_operations/7">hook_node_operations()</a>';
 return $output;
   }
 }
/**
 * Implementation of hook_node_operations().
 * Add siteowner users to list to easily change author to.
 */
function bulk_update_author_node_operations() {
  // Get the correct role data
  $role = user_role_load_by_name('siteowners');
  // Get siteowner users
  $query = db_select('users_roles', 'ur');
  $query->innerJoin('users', 'u', 'ur.uid = u.uid AND ur.rid = :rid', array(':rid' => $role->rid));
  $results = $query
    ->fields('ur', array('uid'))
    ->fields('u', array('name'))
    ->execute()
    ->fetchAllAssoc('uid');
  $operations = array();

  foreach($results as $uid => $result) {
    $operations['author_update_so_' . $result->uid] = array(
      'label' => t('Change author to !name', array('!name' => $result->name)),
      'callback' => 'node_mass_update',
      'callback arguments' => array('updates' => array('uid' => $result->uid)),
    );
  }
  
  return $operations;
}