bcit-ci/CodeIgniter

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Upgrading from 3.0.2 to 3.0.3
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Before performing an update you should take your site offline by
replacing the index.php file with a static one.

Step 1: Update your CodeIgniter files
=====================================

Replace all files and directories in your *system/* directory.

.. note:: If you have any custom developed files in these directories,
    please make copies of them first.

Step 2: Make sure your 'base_url' config value is not empty
===========================================================

When ``$config['base_url']`` is not set, CodeIgniter tries to automatically
detect what your website's base URL is. This is done purely for convenience
when you are starting development of a new application.

Auto-detection is never reliable and also has security implications, which
is why you should **always** have it manually configured!

One of the changes in CodeIgniter 3.0.3 is how this auto-detection works,
and more specifically it now falls back to the server's IP address instead
of the hostname requested by the client. Therefore, if you've ever relied
on auto-detection, it will change how your website works now.

In case you need to allow e.g. multiple domains, or both http:// and
https:// prefixes to be dynamically used depending on the request,
remember that *application/config/config.php* is still a PHP script, in
which you can create this logic with a few lines of code. For example::

    $allowed_domains = array('domain1.tld', 'domain2.tld');
    $default_domain  = 'domain1.tld';

    if (in_array($_SERVER['HTTP_HOST'], $allowed_domains, TRUE))
    {
        $domain = $_SERVER['HTTP_HOST'];
    }
    else
    {
        $domain = $default_domain;
    }

    if ( ! empty($_SERVER['HTTPS']))
    {
        $config['base_url'] = 'https://'.$domain;
    }
    else
    {
        $config['base_url'] = 'http://'.$domain;
    }