CodeIgniter: checking if user logged in for multiple pages

Question

I have a controller, which maps to section of my site and all of the pages within it (methods) should only appear if the user is logged in. Otherwise they should be redirect

Answer 1

You can run code in every method of a Controller by running it in the __construct() method:

function __construct()
{
    parent::__construct();
    if ( ! $this->session->userdata('logged_in'))
    { 
        // Allow some methods?
        $allowed = array(
            'some_method_in_this_controller',
            'other_method_in_this_controller',
        );
        if ( ! in_array($this->router->fetch_method(), $allowed)
        {
            redirect('login');
        }
    }
}

You can remove the "allowed" bits if you want to restrict access to the whole thing, but there are better ways to do this, like creating a base controller:

// Create file application/core/MY_Controller.php
class Auth_Controller extends CI_Controller {

    function __construct()
    {
        parent::__construct();
        if ( ! $this->session->userdata('logged_in'))
        { 
            redirect('login');
        }
    }
}

Then have your restricted controllers extend Auth_Controller instead of CI_Controller. Now your code will be run every time the controller is loaded.

More info on extending core classes: http://www.codeigniter.com/user_guide/general/core_classes.html#extending-core-class

Also of interest: http://php.net/manual/en/language.oop5.decon.php