Limit articles frontend creation by user group

Question

I´m a bit puzzled where to start.

This should happen:

1. admins should be able to edit a Usergroup and define the amount of articles members of this group can create.

2. Before a group member creates/saves a new article in fronted, the amount of articles created by this user is compared to the max allowed articles of it´s group membership. Pseudo Code:

   if ($articlesCreatedByUser < $allowedArticlesByGroup){
     $article->save();
   } else {
     die('you reached the article limit');
   

As I´m just starting with Joomla development here my questions.

• with Joomla3 it´s easy to create integer extra fields for Users, is this possible with Usergroups as well? If not what would be needed to extend the Usergroup backend form?
• what´s the easiest way to limit the article creation form as explained above. I´m unsure if I should dive into plugin creation (and hook into beforesave) or to extend com_content and it´s model save method?

Thanks!

Toni

Answer 1

I would suggest developing a content plugin along with template override to do this task. The below example limits max 5 articles per day per user.

public function onContentBeforeSave($context, $article, $isNew)
{
    if ( $context != 'com_content.form' || !$isNew) 
    {
        return true;
    }

    $user = JFactory::getUser();
    $db = JFactory::getDbo();

    $query = $db->getQuery(true)
        ->select('count(*)')
        ->from('#__content')
        ->where('created_by = '.$user->id.' and created > CURDATE()');
    $db->setQuery($query);
    $articlesCreatedByUser = (int)$db->loadResult();

    // get the allowed articles somehow..
    $allowedArticlesByGroup = 5;

    // check the allowed articles.
    if ($articlesCreatedByUser >= $allowedArticlesByGroup)
    {
        $article->setError('Maximum of '.$allowedArticlesByGroup.' articles are allowed per day.');
        return false;
    }

    return true;
}

The plugin will prevent users from creating new articles beyond the allowed limit. Now to prevent users from accessing the create article page itself, override the form layout and add above logic.