get_canonical OOP

get_canonical.php

<?php
return;
error_reporting(E_ALL);
ini_set('display_errors', 1);


class Canonical
{
    public $modx = null;
    public $resourseId;
    public $contextKey;
    public $test;
    
    function __construct(modx &$modx)
    {
        $this->modx         = & $modx;
        $this->resourseId   = $this->modx->resource->get('id');
        $this->contextKey   = $this->modx->context->get('key');
        $this->test = 'test string';
    }
}

$link = new Canonical($modx);
echo $link->contextKey;