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Tutorials Adding User or Device Limits Simple Paid App

This document outlines how to implement user limits for a paid app. If plan on having multiple tiers for an app (for example, a free and a paid version), please read through this example and then jump to the Multiple Tiers example.

Subscription Class

In this example, we have a single paid app called Acme limited to 10 users. As described in the user limits document, the Acme app requires a subscription class with a single get_info() method. Here is an example to get you started:

    public function get_info()
        clearos_profile(__METHOD__, __LINE__);
        // Fill in the total, used and available data with actual data.
        $info = array(
            'app_name' => lang('acme_app_name'),
            'type' => Subscription_Engine::TYPE_USER,
            'total' => 10,
            'used' => 10,
            'available' => 0,
        // The Acme app uses an LDAP extension: acme_extension. For the 
        // "User" app, we specify the attribute that should be disabled 
        // once the limit has been reached.
        $info['user_limit']['extension']['acme'] = array('account_flag');
        return $info;

You can find the full source code here:

Please take special note of the following line in the get_info() method:

$info['user_limit']['extension']['acme'] = array('account_flag');

This definition will prevent the “account_flag” in the Acme LDAP extension from being set when the limit has been reached. Remember, this is just a convenience feature for the end user to prevent accidentally going over user limits.


With the Acme_Subscription class completed, it can be activated by creating the acme file in /var/clearos/clearcenter/subscriptions.

touch /var/clearos/clearcenter/subscriptions/acme

As a sanity check, go to the System|Accounts|Users in the menu. Manually set the number of available licenses in your subscription class to return zero, and you should see a warning in the Users app similar to the screenshot below.

To finish up your paid app, make sure the equivalent of the /var/clearos/clearcenter/subscriptions/acme file is included in your apps deploy/info.php file!

content/en_us/dev_framework_tutorials_adding_user_or_device_limits_simple_paid_app.txt · Last modified: 2015/03/01 17:17 (external edit)