# Upgrading from 2.2.x to 3.0.x

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 and replace your index.php file. If any modifications were made to your index.php they will need to be made fresh in this new one.

Important

You have to delete the old system/ directory first and then put the new one in its place. A simple copy-paste may cause issues.

Note

If you have any custom developed files in these folders please make copies of them first.

## Step 2: Update your classes file names

Starting with CodeIgniter 3.0, all class filenames (libraries, drivers, controllers and models) must be named in a Ucfirst-like manner or in other words - they must start with a capital letter.

For example, if you have the following library file:

> application/libraries/mylibrary.php

... then you’ll have to rename it to:

> application/libraries/Mylibrary.php

The same goes for driver libraries and extensions and/or overrides of CodeIgniter’s own libraries and core classes.

> application/libraries/MY_email.php application/core/MY_log.php

The above files should respectively be renamed to the following:

> application/libraries/MY_Email.php application/core/MY_Log.php

Controllers:

> application/controllers/welcome.php -> application/controllers/Welcome.php

Models:

> application/models/misc_model.php -> application/models/Misc_model.php

Please note that this DOES NOT affect directories, configuration files, views, helpers, hooks and anything else - it is only applied to classes.

You must now follow just one simple rule - class names in Ucfirst and everything else in lowercase.

## Step 3: Replace config/mimes.php

This config file has been updated to contain more user mime-types, please copy it to _application/config/mimes.php*.

## Step 4: Remove $autoload[‘core’] from your config/autoload.php

Use of the `$autoload['core']` config array has been deprecated as of CodeIgniter 1.4.1 and is now removed. Move any entries that you might have listed there to `$autoload['libraries']` instead.

## Step 5: Move your Log class overrides or extensions

The Log Class is considered as a “core” class and is now located in the system/core/ directory. Therefore, in order for your Log class overrides or extensions to work, you need to move them to application/core/:

> application/libraries/Log.php -> application/core/Log.php application/libraries/MY_Log.php -> application/core/MY_Log.php

## Step 6: Update your Session library usage

The Session Library has been completely re-written in CodeIgniter 3 and now comes with a bunch of new features, but that also means that there are changes that you should make ...

Most notably, the library now uses separate storage drivers instead of always relying on (encrypted) cookies. In fact, cookies as storage have now been removed and you must always use some kind of server-side storage engine, with the file-system being the default option.

The Session Class now utilizes PHP’s own mechanisms for building custom session handlers, which also means that your session data is now accessible via the `$_SESSION` superglobal (though, we’ve kept the possibility to use it as “userdata”, like you’ve done until now).

A few configuration options have been removed and a few have been added. You should really read the whole Session library manual for the details, but here’s a short list of changes that you should make:

> - Set your `$config['sess_driver']` value

>   It will default to ‘files’, unles you’ve previously used `$config['sess_use_database']`, in which case it will be set to ‘database’.

> - Set a `$config['sess_save_path']` value

>   For the ‘database’ driver, a fallback to `$config['sess_table_name']` is in place, but otherwise requires you to read the manual for the specific driver of your choice.

> - Update your `ci_sessions` table (‘database’ driver only)

>   The table structure has changed a bit, and more specifically:

>   > - `session_id` field is renamed to `id`
>   > - `user_agent` field is dropped
>   > - `user_data` field is renamed to `data` and under MySQL is now of type BLOB
>   > - `last_activity` field is renamed to `timestamp`

>   This is accompanied by a slight change in the table indexes too, so please read the manual about the Session Database Driver for more information.

>   Important

>   Only MySQL and PostgreSQL are officially supported now. Other databases may still work, but due to lack of advisory locking features, they are unsafe for concurrent requests and you should consider using another driver instead.

> - Remove `$config['sess_match_useragent']`

>   The user-agent string is input supplied by the user’s browser, or in other words: client side input. As such, it is an ineffective feature and hence why it has been removed.

> - Remove `$config['sess_encrypt_cookie']`

>   As already noted, the library no longer uses cookies as a storage mechanism, which renders this option useless.

> - Remove `$config['sess_expire_on_close']`

>   This option is still usable, but only for backwards compatibility purposes and it should be otherwise removed. The same effect is achieved by setting `$config['sess_expiration']` to 0.

> - Check “flashdata” for collisions with “userdata”

>   Flashdata is now just regular “userdata”, only marked for deletion on the next request. In other words: you can’t have both “userdata” and “flashdata” with the same name, because it’s the same thing.

> - Check usage of session metadata

>   Previously, you could access the ‘session_id’, ‘ip_address’, ‘user_agent’ and ‘last_activity’ metadata items as userdata. This is no longer possible, and you should read the notes about Session Metadata if your application relies on those values.

> - Check `unset_userdata()` usage

>   Previously, this method used to accept an associative array of `'key' => 'dummy value'` pairs for unsetting multiple keys. That however makes no sense and you now have to pass only the keys, as the elements of an array.

>       // Old
>       $this->session->unset_userdata(array('item' => '', 'item2' => ''));

>       // New
>       $this->session->unset_userdata(array('item', 'item2'));

Finally, if you have written a Session extension, you must now move it to the application/libraries/Session/ directory, although chances are that it will now also have to be re-factored.

## Step 7: Update your config/database.php

Due to 3.0.0’s renaming of Active Record to Query Builder, inside your config/database.php, you will need to rename the `$active_record` variable to `$query_builder`:

    $active_group = 'default';
    // $active_record = TRUE;
    $query_builder = TRUE;

## Step 8: Replace your error templates

In CodeIgniter 3.0, the error templates are now considered as views and have been moved to the _application/views/errors* directory.

Furthermore, we’ve added support for CLI error templates in plain-text format that unlike HTML, is suitable for the command line. This of course requires another level of separation.

It is safe to move your old templates from _application/errors* to _application/views/errors/html*, but you’ll have to copy the new _application/views/errors/cli* directory from the CodeIgniter archive.

## Step 9: Update your config/routes.php file

### Routes containing :any

Historically, CodeIgniter has always provided the :any wildcard in routing, with the intention of providing a way to match any character within an URI segment.

However, the :any wildcard is actually just an alias for a regular expression and used to be executed in that manner as .+. This is considered a bug, as it also matches the / (forward slash) character, which is the URI segment delimiter and that was never the intention.

In CodeIgniter 3, the :any wildcard will now represent [^/]+, so that it will not match a forward slash.

There are certainly many developers that have utilized this bug as an actual feature. If you’re one of them and want to match a forward slash, please use the .+ regular expression:

    (.+)    // matches ANYTHING
    (:any)  // matches any character, except for '/'

### Directories and ‘default_controller’, ‘404_override’

As you should know, the `$route['default_controller']` and `$route['404_override']` settings accept not only a controller name, but also controller/method pairs. However, a bug in the routing logic has made it possible for some users to use that as directory/controller instead.

As already said, this behavior was incidental and was never intended, nor documented. If you’ve relied on it, your application will break with CodeIgniter 3.0.

Another notable change in version 3 is that ‘default_controller’ and ‘404_override’ are now applied per directory. To explain what this means, let’s take the following example:

    $route['default_controller'] = 'main';

Now, assuming that your website is located at example.com, you already know that if a user visits `http://example.com/`, the above setting will cause your ‘Main’ controller to be loaded.

However, what happens if you have an application/controllers/admin/ directory and the user visits `http://example.com/admin/`? In CodeIgniter 3, the router will look for a ‘Main’ controller under the admin/ directory as well. If not found, a Not Found (404) will be triggered.

The same rule applies to the ‘404_override’ setting.

## Step 10: Many functions now return NULL instead of FALSE on missing items

Many methods and functions now return NULL instead of FALSE when the required items don’t exist:

> - Common functions
>   - config_item()
> - Config Class
>   - config->item()
>   - config->slash_item()
> - Input Class
>   - input->get()
>   - input->post()
>   - input->get_post()
>   - input->cookie()
>   - input->server()
>   - input->input_stream()
>   - input->get_request_header()
> - Session Class
>   - session->userdata()
>   - session->flashdata()
> - URI Class
>   - uri->segment()
>   - uri->rsegment()
> - Array Helper
>   - element()
>   - elements()

## Step 11: Usage of XSS filtering

Many functions in CodeIgniter allow you to use its XSS filtering feature on demand by passing a boolean parameter. The default value of that parameter used to be boolean FALSE, but it is now changed to NULL and it will be dynamically determined by your `$config['global_xss_filtering']` value.

If you used to manually pass a boolean value for the `$xss_filter` parameter or if you’ve always had `$config['global_xss_filtering']` set to FALSE, then this change doesn’t concern you.

Otherwise however, please review your usage of the following functions:

> - Input Library
>   - input->get()
>   - input->post()
>   - input->get_post()
>   - input->cookie()
>   - input->server()
>   - input->input_stream()
> - Cookie Helper `get_cookie()`

Important

Another related change is that the `$_GET`, `$_POST`, `$_COOKIE` and `$_SERVER` superglobals are no longer automatically overwritten when global XSS filtering is turned on.

## Step 12: Check for potential XSS issues with URIs

The URI Library used to automatically convert a certain set of “programmatic characters” to HTML entities when they are encountered in a URI segment.

This was aimed at providing some automatic XSS protection, in addition to the `$config['permitted_uri_chars']` setting, but has proven to be problematic and is now removed in CodeIgniter 3.0.

If your application has relied on this feature, you should update it to filter URI segments through `$this->security->xss_clean()` whenever you output them.

## Step 13: Check for usage of the ‘xss_clean’ Form validation rule

A largely unknown rule about XSS cleaning is that it should only be applied to output, as opposed to input data.

We’ve made that mistake ourselves with our automatic and global XSS cleaning feature (see previous step about XSS above), so now in an effort to discourage that practice, we’re also removing ‘xss_clean’ from the officially supported list of form validation rules.

Because the Form Validation library generally validates input data, the ‘xss_clean’ rule simply doesn’t belong in it.

If you really, really need to apply that rule, you should now also load the Security Helper, which contains `xss_clean()` as a regular function and therefore can be also used as a validation rule.

## Step 14: Update usage of Input Class’s get_post() method

Previously, the Input Class method `get_post()` was searching first in POST data, then in GET data. This method has been modified so that it searches in GET then in POST, as its name suggests.

A method has been added, `post_get()`, which searches in POST then in GET, as `get_post()` was doing before.

## Step 15: Update usage of Directory Helper’s directory_map() function

In the resulting array, directories now end with a trailing directory separator (i.e. a slash, usually).

## Step 16: Update usage of Database Forge’s drop_table() method

Up until now, `drop_table()` added an IF EXISTS clause by default or it didn’t work at all with some drivers. In CodeIgniter 3.0, the IF EXISTS condition is no longer added by default and has an optional second parameter that allows that instead and is set to FALSE by default.

If your application relies on IF EXISTS, you’ll have to change its usage.

    // Now produces just DROP TABLE `table_name`
    $this->dbforge->drop_table('table_name');

    // Produces DROP TABLE IF EXISTS `table_name`
    $this->dbforge->drop_table('table_name', TRUE);

Note

The given example uses MySQL-specific syntax, but it should work across all drivers with the exception of ODBC.

## Step 17: Change usage of Email library with multiple emails

The Email Library will automatically clear the set parameters after successfully sending emails. To override this behaviour, pass FALSE as the first parameter in the `send()` method:

    if ($this->email->send(FALSE))
    {
            // Parameters won't be cleared
    }

## Step 18: Update your Form_validation language lines

Two improvements have been made to the Form Validation Library‘s language files and error messages format:

> - Language Library line keys now must be prefixed with form_validation_ in order to avoid collisions:

>       // Old
>       $lang['rule'] = ...

>       // New
>       $lang['form_validation_rule'] = ...

> - The error messages format has been changed to use named parameters, to allow more flexibility than what sprintf() offers:

>       // Old
>       'The %s field does not match the %s field.'

>       // New
>       'The {field} field does not match the {param} field.'

Note

The old formatting still works, but the non-prefixed line keys are DEPRECATED and scheduled for removal in CodeIgniter 3.1+. Therefore you’re encouraged to update its usage sooner rather than later.

## Step 19: 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;
    }

## Step 20: Remove usage of (previously) deprecated functionalities

In addition to the `$autoload['core']` configuration setting, there’s a number of other functionalities that have been removed in CodeIgniter 3.0.0:

### The SHA1 library

The previously deprecated SHA1 library has been removed, alter your code to use PHP’s native `sha1()` function to generate a SHA1 hash.

Additionally, the `sha1()` method in the Encrypt Library has been removed.

### The EXT constant

Usage of the `EXT` constant has been deprecated since dropping support for PHP 4. There’s no longer a need to maintain different filename extensions and in this new CodeIgniter version, the `EXT` constant has been removed. Use just ‘.php’ instead.

### Smiley helper

The Smiley Helper is a legacy feature from EllisLab’s ExpressionEngine product. However, it is too specific for a general purpose framework like CodeIgniter and as such it is now deprecated.

Also, the previously deprecated `js_insert_smiley()` (since version 1.7.2) is now removed.

### The Encrypt library

Following numerous vulnerability reports, the Encrypt Library has been deprecated and a new, Encryption Library is added to take its place.

The new library requires either the MCrypt extension (and /dev/urandom availability) or PHP 5.3.3 and the OpenSSL extension. While this might be rather inconvenient, it is a requirement that allows us to have properly implemented cryptographic functions.

Note

The Encrypt Library is still available for the purpose of keeping backwards compatibility.

Important

You are strongly encouraged to switch to the new Encryption Library as soon as possible!

### The Cart library

The Cart Library, similarly to the Smiley Helper is too specific for CodeIgniter. It is now deprecated and scheduled for removal in CodeIgniter 3.1+.

Note

The library is still available, but you’re strongly encouraged to remove its usage sooner rather than later.

### Database drivers ‘mysql’, ‘sqlite’, ‘mssql’, ‘pdo/dblib’

The mysql driver utilizes the old ‘mysql’ PHP extension, known for its aging code base and many low-level problems. The extension is deprecated as of PHP 5.5 and CodeIgniter deprecates it in version 3.0, switching the default configured MySQL driver to mysqli.

Please use either the ‘mysqli’ or ‘pdo/mysql’ drivers for MySQL. The old ‘mysql’ driver will be removed at some point in the future.

The sqlite, mssql and pdo/dblib (also known as pdo/mssql or pdo/sybase) drivers all depend on PHP extensions that for different reasons no longer exist since PHP 5.3.

Therefore we are now deprecating these drivers as we will have to remove them in one of the next CodeIgniter versions. You should use the more advanced, sqlite3, sqlsrv or pdo/sqlsrv drivers respectively.

Note

These drivers are still available, but you’re strongly encouraged to switch to other ones sooner rather than later.

### Security helper do_hash()

Security Helper function `do_hash()` is now just an alias for PHP’s native `hash()` function. It is deprecated and scheduled for removal in CodeIgniter 3.1+.

Note

This function is still available, but you’re strongly encouraged to remove its usage sooner rather than later.

### The $config[‘global_xss_filtering’] setting

As already explained above, XSS filtering should not be done on input data, but on output instead. Therefore, the `$config['global_xss_filtering']`, which automatically filters input data, is considered a bad practice and is now deprecated.

Instead, you should manually escape any user-provided data via the `xss_clean()` function when you need to output it, or use a library like HTML Purifier that does that for you.

Note

The setting is still available, but you’re strongly encouraged to remove its usage sooner rather than later.

### File helper read_file()

File Helper function `read_file()` is now just an alias for PHP’s native `file_get_contents()` function. It is deprecated and scheduled for removal in CodeIgniter 3.1+.

Note

This function is still available, but you’re strongly encouraged to remove its usage sooner rather than later.

### String helper repeater()

String Helper function `repeater()` is now just an alias for PHP’s native `str_repeat()` function. It is deprecated and scheduled for removal in CodeIgniter 3.1+.

Note

This function is still available, but you’re strongly encouraged to remove its usage sooner rather than later.

### String helper trim_slashes()

String Helper function `trim_slashes()` is now just an alias for PHP’s native `trim()` function (with a slash passed as its second argument). It is deprecated and scheduled for removal in CodeIgniter 3.1+.

Note

This function is still available, but you’re strongly encouraged to remove its usage sooner rather than later.

### Form helper form_prep()

Form Helper function `form_prep()` is now just an alias for common function `html_escape()`. It is deprecated and will be removed in the future.

Please use `html_escape()` instead.

Note

This function is still available, but you’re strongly encouraged to remove its usage sooner rather than later.

### Email helper functions

Email Helper only has two functions

> - `valid_email()`
> - `send_email()`

Both of them are now aliases for PHP’s native `filter_var()` and `mail()` functions, respectively. Therefore the Email Helper altogether is being deprecated and is scheduled for removal in CodeIgniter 3.1+.

Note

These functions are still available, but you’re strongly encouraged to remove their usage sooner rather than later.

### Date helper standard_date()

Date Helper function `standard_date()` is being deprecated due to the availability of native PHP constants, which when combined with `date()` provide the same functionality. Furthermore, they have the exact same names as the ones supported by `standard_date()`. Here are examples of how to replace its usage:

    // Old way
    standard_date(); // defaults to standard_date('DATE_RFC822', now());

    // Replacement
    date(DATE_RFC822, now());

    // Old way
    standard_date('DATE_ATOM', $time);

    // Replacement
    date(DATE_ATOM, $time);

Note

This function is still available, but you’re strongly encouraged to remove its usage sooner rather than later as it is scheduled for removal in CodeIgniter 3.1+.

### HTML helpers nbs(), br()

HTML Helper functions `nbs()` and `br()` are just aliases for the native `str_repeat()` function used with `&nbsp;` and `<br >` respectively.

Because there’s no point in just aliasing native PHP functions, they are now deprecated and scheduled for removal in CodeIgniter 3.1+.

Note

These functions are still available, but you’re strongly encouraged to remove their usage sooner rather than later.

### Pagination library ‘anchor_class’ setting

The Pagination Library now supports adding pretty much any HTML attribute to your anchors via the ‘attributes’ configuration setting. This includes passing the ‘class’ attribute and using the separate ‘anchor_class’ setting no longer makes sense. As a result of that, the ‘anchor_class’ setting is now deprecated and scheduled for removal in CodeIgniter 3.1+.

Note

This setting is still available, but you’re strongly encouraged to remove its usage sooner rather than later.

### String helper random_string() types ‘unique’ and ‘encrypt’

When using the String Helper function `random_string()`, you should no longer pass the unique and encrypt randomization types. They are only aliases for md5 and sha1 respectively and are now deprecated and scheduled for removal in CodeIgniter 3.1+.

Note

These options are still available, but you’re strongly encouraged to remove their usage sooner rather than later.

### URL helper url_title() separators ‘dash’ and ‘underscore’

When using the URL Helper function `url_title()`, you should no longer pass dash or underscore as the word separator. This function will now accept any character and you should just pass the chosen character directly, so you should write ‘-‘ instead of ‘dash’ and ‘_’ instead of ‘underscore’.

dash and underscore now act as aliases and are deprecated and scheduled for removal in CodeIgniter 3.1+.

Note

These options are still available, but you’re strongly encouraged to remove their usage sooner rather than later.

### Session Library method all_userdata()

As seen in the Change Log, Session Library method `userdata()` now allows you to fetch all userdata by simply omitting its parameter:

    $this->session->userdata();

This makes the `all_userdata()` method redudant and therefore it is now just an alias for `userdata()` with the above shown usage and is being deprecated and scheduled for removal in CodeIgniter 3.1+.

Note

This method is still available, but you’re strongly encouraged to remove its usage sooner rather than later.

### Database Forge method add_column() with an AFTER clause

If you have used the third parameter for Database Forge method `add_column()` to add a field for an AFTER clause, then you should change its usage.

That third parameter has been deprecated and scheduled for removal in CodeIgniter 3.1+.

You should now put AFTER clause field names in the field definition array instead:

    // Old usage:
    $field = array(
            'new_field' => array('type' => 'TEXT')
    );

    $this->dbforge->add_column('table_name', $field, 'another_field');

    // New usage:
    $field = array(
            'new_field' => array('type' => 'TEXT', 'after' => 'another_field')
    );

    $this->dbforge->add_column('table_name', $field);

Note

The parameter is still available, but you’re strongly encouraged to remove its usage sooner rather than later.

Note

This is for MySQL and CUBRID databases only! Other drivers don’t support this clause and will silently ignore it.

### URI Routing methods fetch_directory(), fetch_class(), fetch_method()

With properties `CI_Router::$directory`, `CI_Router::$class` and `CI_Router::$method` being public and their respective `fetch_*()` no longer doing anything else to just return the properties - it doesn’t make sense to keep them.

Those are all internal, undocumented methods, but we’ve opted to deprecate them for now in order to maintain backwards-compatibility just in case. If some of you have utilized them, then you can now just access the properties instead:

    $this->router->directory;
    $this->router->class;
    $this->router->method;

Note

Those methods are still available, but you’re strongly encouraged to remove their usage sooner rather than later.

### Input library method is_cli_request()

Calls to the `CI_Input::is_cli_request()` method are necessary at many places in the CodeIgniter internals and this is often before the Input Library is loaded. Because of that, it is being replaced by a common function named `is_cli()` and this method is now just an alias.

The new function is both available at all times for you to use and shorter to type.

    // Old
    $this->input->is_cli_request();

    // New
    is_cli();

`CI_Input::is_cli_request()` is now now deprecated and scheduled for removal in CodeIgniter 3.1+.

Note

This method is still available, but you’re strongly encouraged to remove its usage sooner rather than later.

### Config library method system_url()

Usage of `CI_Config::system_url()` encourages insecure coding practices. Namely, your CodeIgniter system/ directory shouldn’t be publicly accessible from a security point of view.

Because of this, this method is now deprecated and scheduled for removal in CodeIgniter 3.1+.

Note

This method is still available, but you’re strongly encouraged to remove its usage sooner rather than later.

#### The Javascript library

The Javascript Library has always had an ‘experimental’ status and was never really useful, nor a proper solution.

It is now deprecated and scheduled for removal in CodeIgniter 3.1+.

Note

This library is still available, but you’re strongly encouraged to remove its usage sooner rather than later.

## Step 21: Check your usage of Text helper highlight_phrase()

The default HTML tag used by Text Helper function `highlight_phrase()` has been changed from `<strong>` to the new HTML5 tag `<mark>`.

Unless you’ve used your own highlighting tags, this might cause trouble for your visitors who use older web browsers such as Internet Explorer 8. We therefore suggest that you add the following code to your CSS files in order to avoid backwards compatibility with old browsers:

    mark {
            background: #ff0;
            color: #000;
    };