'Controller::beforeFilter' implementation in CodeIgniter2 example

config_hooks.php

<?php # File: application/config/hooks.php

# . . . 

$hook['post_controller_constructor'] = [
    'class'    => 'ControllerHook',
    'function' => 'beforeFilter',
    'filename' => 'controller.php',
    'filepath' => 'hooks',
    'params'   => []
];

# . . . 

controllers_examples.php

<?php # File: application/controller/examples.php
if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class Examples extends MY_Controller
{
    # . . . 
    
    public function index()
    {
        // localhost/app/examples
        // MY_Controller::testBeforeFilter() will run before to call this->index()
        var_dump(__METHOD__);
    }
    
    # . . . 
}

core_MY_Controller.php

<?php # File: application/core/MY_Controller.php

if (!defined('BASEPATH')) {
    exit('No direct script access allowed');
}

/**
 * Clase base que extiende el funcionamiento del controlador base del sistema.
 */
class MY_Controller extends CI_Controller
{
    
    # . . . 
    
    protected function testBeforeFilter($action)
    {       
       var_dump(__METHOD__, $action);
    }


    /**
     * Before to filter implementation.
     * This method is called before controller actions, and after constructor.
     * 
     * @return void
     * */
    public function beforeFilter()
    {
        $calledAction = $this->router->fetch_method();
        $this->testBeforeFilter($calledAction);
    }
    
    # . . . 
}

hooks_controller.php

<?php # File: application/hooks/controller.php

if ( ! defined('BASEPATH')) exit('No direct script access allowed');

/**
 * Hook to provide some functions to controllers.
 *
 * @author Nelson Martell <nelson6e65-dev@yahoo.es>
 */
class ControllerHook
{
    private $ci;

    public function __construct()
    {
        $this->ci =& get_instance();

        // var_dump($this->ci->router);
        $this->ci->load->library('session');
        $this->ci->load->helper('url');
    }


    /**
     * Methoth that will be called before controller actions calls.
     *
     * @return void
     */
    public function beforeFilter()
    {
        // $called_function = $this->ci->router->fetch_method();

        if (method_exists($this->ci, 'beforeFilter')) {
            return $this->ci->beforeFilter();
        }

    }


}