When using a central index.php file for accessing other pages, what are the considerations for implementing additional authentication for specific modules within the application?

When implementing additional authentication for specific modules within an application using a central index.php file, one approach is to check the user's authentication status before loading the requested module. This can be achieved by setting up a session variable upon successful login and checking this variable before including the module's file. By adding this check to the central index.php file, you can ensure that only authenticated users can access certain modules within the application.

session_start();

// Check if the user is authenticated
if (!isset($_SESSION['authenticated']) || $_SESSION['authenticated'] !== true) {
    // Redirect to login page or display an error message
    header('Location: login.php');
    exit();
}

// Include the requested module based on the query parameter
if (isset($_GET['module'])) {
    $module = $_GET['module'];
    if (file_exists($module . '.php')) {
        include $module . '.php';
    } else {
        // Handle invalid module request
        echo 'Module not found';
    }
} else {
    // Handle no module specified
    echo 'No module specified';
}