I have been looking around the Tank auth code to see how things are done, but it seems a little confusing to find out how to change the path of the default login.
I wanted to change it to groups/login or users/sign_in, but that wasn't an easy task. I'm wondering whether I should change that from the routing file or any other file.
Any idea how to get around with this little issue?
I'm wondering whether I should change that from the routing file
Yes, that's exactly what URI Routing is for:
$route['your/desired/url'] = 'auth/login';
If you need to kill the old URL for some reason, you can set it to something empty:
$route['auth/login'] = FALSE;
Unfortunately, the Tank Auth login url is assumed to be auth/login, and there are several redirects that must be edited. I recommend adding a custom config setting to config/tank_auth.php:
$config['login_url'] = 'your/desired/url';
Then replace all occurrences of redirect('/auth/login') with:
redirect($this->config->item('login_url', 'tank_auth'));
in the Auth controller and anywhere else it appears.