Manger Menu item running a snippet

Modx 2.2.4
PHP : 5.6.10
MySql : 5.5.42

I want to update some TV for a batch of resources. I installed Batcher 1.1.1, but Batcher no longer able to batch TV (https://github.com/splittingred/Batcher/issues/30).

I have a snippet that can replace a TV value for a batch of resources.

I am exploring another option, running my snippet via a Manager menu item.

I try the example « Custom Manager Pages in 2.3 » in Modx documentation, no problem it working well.

Not being too familiar with the notion of class and public function, how do I write a « Controller File » for running my snippet?

Thank for your help

This probably won't work, but it's worth a try:

Create a new menu item in System -> Menus

Leave the action blank and use core for the namespace.

In the handler field, put this:

It does not work.

This the code of the Controller File of the Modx Docs «Custom Manager Pages in 2.3» :

<?php
class MycmpWelcomeManagerController extends modExtraManagerController {
public function process(array $scriptProperties = array()) {}
public function getPageTitle() {
return 'My Test CMP';
}
public function getTemplateFile() {
return 'welcome.tpl';
}
}

Is it possible to write a Controller File like this that will run my snippet?

Thank you for your generous assistance