Keep Tank Auth on every page in CodeIgniter - codeigniter

Question

My question is a little hard to explain, but I'll try..
Basically, in the tank_auth example script there is this code to redirect the user if they are not already logged on;
if (!$this->tank_auth->is_logged_in()) {
redirect('/auth/login/');
} else {
$data['user_id'] = $this->tank_auth->get_user_id();
$data['username'] = $this->tank_auth->get_username();
$this->load->view('welcome', $data);
}
Which is great if you have a login page and the user starts at the beginning each time. (And I'm comfortable doing it that way)
But I want the user to be able to jump in to website at (almost) any controller and have a login bar come up across the top. When logging in, it should not redirect them to another page. They should end up on the same page they tried to visit.
For example, my user might load straight away example.com/food/burgers. I'd like a blank page to come up, but just with a login bar across the top. Then when they log in, they end up back on the 'burgers' page but this time there is also a list of burgers and the bar accross the top that tells them they are logged in, with the option to log-off.
So how do I do this? Do I need to call the auth/login method from every controller? Do I do it as an "include"? No idea.

Answer 1

Firstly you will want to create a base controller that all your controllers will extend from. You would check for authentication in this base controller. If they aren't logged in, then save the entry point uri in a cookie and redirect to the login page.
// application/core/My_Controller.php
class MY_Controller extends CI_Controller
{
public function __construct()
{
parent::__construct();
$this->load->library('session');
$this->load->model('tank_auth');
if (!$this->tank_auth->is_logged_in()) {
// save the visitors entry point and redirect to login
$this->session->set_userdata('redirect', $this->uri->uri_string());
redirect('auth/login');
}
}
}
Your main controllers will extend MY_Controller and don't need to worry about authentication.
class Welcome extends MY_Controller
{
public function index()
{
$data['user_id'] = $this->tank_auth->get_user_id();
$data['username'] = $this->tank_auth->get_username();
$this->load->view('welcome', $data);
}
}
Your authentication controller wouldn't extend MY_Controller otherwise it will get stuck in a redirect loop.
class Auth extends CI_Controller
{
public function login()
{
$this->load->library('session');
if (auth_success) {
// redirect the user back to the entry point or the welcome controller
if ($uri = $this->session->userdata('redirect')) {
redirect($uri);
} else {
redirect('welcome');
}
}
// handle authentication failure
}
}
Instead of using sessions to store the redirect uri, you could also pass it along as a GET parameter.