Question

How can I authenticate Codeigniter user, without using login form?

Ie, if he have cookie with some specific value or he is redirected from some specific link, to be authenticated automatically?

Answer 1

Assuming both applications are on CodeIgniter – You must agree upon some parameters between your application and the third-party that will be issuing the cookie.

Head into config/config.php and have both parties set (at the least):

$config['sess_cookie_name'] and $config['cookie_prefix'] to be the same values.

If you decide to encrypt your session, you must also agree upon an encryption key between the third party and your application and set the $config['encryption_key'] value appropriately.

Lastly, and perhaps most importantly, you must set the cookie domain, $config['cookie_domain'] or CodeIgniter will reject it.

You can then get and set session cookies using $this->session->userdata() and $this->session->set_userdata(), respectively.

I’ve never tried this before, so I can’t really vouch or support to great length any issues that may arise, but hopefully it sets you on the some path to success.