adcfi/action/desconectar.php

<?php
require_once "{$_SERVER['DOCUMENT_ROOT']}/dependencies.php";

use Respect\Validation\Validator as v;

// only requre POST ['action' => 'desconectar' | 'sign-out']
methods([
    'POST' => v::keySet(
        v::key('action', v::stringType()->notEmpty()->in(['desconectar', 'sign-out']))
    ), 'GET' => v::alwaysValid()
]);

if ($_SERVER['REQUEST_METHOD'] === 'GET') {
    session_destroy();
} else
    switch ($_POST['action']) {
        case 'desconectar':
            unset($_SESSION['page']);
            unset($_SESSION['moodle_db']);
            break;

        case 'sign-out':
            session_destroy();
            break;
    }

header('Location: /');