Page is not working — ERR_TOO_MANY_REDIRECTS

Question

When this code implement in codeigniter (this type of error show => localhost redirected you too many times.)

1)application/config/config.php

    $config['enable_hooks'] = TRUE;

2)application/config/hooks.php

    $hook['post_controller_constructor'][] = array(
        'function' => 'checkAdminLogin',
        'filename' => 'authenticate_login.php',
        'filepath' => 'hooks',
    );

3)application/hooks/authenticate_login.php (make new php file (authenticate_login.php))

    function checkAdminLogin() {
        $CI = & get_instance();
        if (!getSession('is_logged_in')) {
            redirect('admin/login');
        } else
            return true;
    }

    function getSession($key) {
        $CI = & get_instance();
        return $CI->session->userdata(trim($key));
    }

Answer 1

When your visitor goes to admin/login your code will detect that he is not logged in and redirect it again to admin/login....and over, and over again...

You must detect login page route and not redirect from it.

Something like:

function checkAdminLogin() {
    $CI = & get_instance();
    if (!getSession('is_logged_in'))
    {
        if ($_SERVER['REQUEST_URI']!='/admin/login') {
            redirect('admin/login');
        }else{
            // User is on login page, don't redirect him again
        }
    } else
        return true;
}

But I'm not sure what returning true means in your case. Basically you have 3 cases here:

1. Logged in
2. Not logged in, but on login page
3. Not logged in and not on login page

So you have to think of all those 3.