codeigniter check for user session in every controller

Question

Another option is to create a base controller. Place the function in the base controller and then inherit from this.

To achieve this in CodeIgniter, create a file called MY_Controller.php in the libraries folder of your application.

class MY_Controller extends Controller
{
    public function __construct()
    {
        parent::__construct();
    }

    public function is_logged_in()
    {
        $user = $this->session->userdata('user_data');
        return isset($user);
    }
}

Then make your controller inherit from this base controller.

class X extends MY_Controller
{
    public function __construct()
    {
        parent::__construct();
    }

    public function do_something()
    {
        if ($this->is_logged_in())
        {
            // User is logged in.  Do something.
        }
    }
}

Put it in a helper and autoload it.

helpers/login_helper.php:

function is_logged_in() {
    // Get current CodeIgniter instance
    $CI =& get_instance();
    // We need to use $CI->session instead of $this->session
    $user = $CI->session->userdata('user_data');
    if (!isset($user)) { return false; } else { return true; }
}

config/autoload.php:

$autoload['helper'] = array('login');

Then in your controller you can call:

is_logged_in();

You can achieve this using helper and CodeIgniter constructor.

1. You can create custom helper my_helper.php in that write your function

   function is_logged_in() {
     $user = $this->session->userdata('user_data');
     if (!isset($user)) { 
      return false; 
     } 
    else { 
      return true;
    }
   } 
   

2. In controller if its login.php

   class Login extends CI_Controller {
   
       public function __construct()
       {
           parent::__construct();
           if(!is_logged_in())  // if you add in constructor no need write each function in above controller. 
           {
            //redirect you login view
           }
       }
   

I think using hooks is pretty easy. Just create a hook to check $this->session->user. It will be called in every request.