URI Routing

What is URI Routing?

URI Routing associates a URI with a controller’s method.

CodeIgniter has two kinds of routing. One is Defined Route Routing, and the other is Auto Routing. With Defined Route Routing, you can define routes manually. It allows flexible URL. Auto Routing automatically routes HTTP requests based on conventions and execute the corresponding controller methods. There is no need to define routes manually.

First, let’s look at Defined Route Routing. If you want to use Auto Routing, see Auto Routing (Improved).

Setting Routing Rules

Routing rules are defined in the app/Config/Routes.php file. In it you’ll see that it creates an instance of the RouteCollection class ($routes) that permits you to specify your own routing criteria. Routes can be specified using placeholders or Regular Expressions.

When you specify a route, you choose a method to corresponding to HTTP verbs (request method). If you expect a GET request, you use the get() method:

<?php

$routes->get('/', 'Home::index');

A route takes the Route Path (URI path relative to the BaseURL. /) on the left, and maps it to the Route Handler (controller and method Home::index) on the right, along with any parameters that should be passed to the controller.

The controller and method should be listed in the same way that you would use a static method, by separating the class and its method with a double-colon, like Users::list.

If that method requires parameters to be passed to it, then they would be listed after the method name, separated by forward-slashes:

<?php

// Calls $Users->list()
$routes->get('users', 'Users::list');

// Calls $Users->list(1, 23)
$routes->get('users/1/23', 'Users::list/1/23');

Examples

Here are a few basic routing examples.

A URL containing the word journals in the first segment will be mapped to the \App\Controllers\Blogs class, and the default method, which is usually index():

<?php

$routes->get('journals', 'Blogs');

A URL containing the segments blog/joe will be mapped to the \App\Controllers\Blogs class and the users() method. The ID will be set to 34:

<?php

$routes->get('blog/joe', 'Blogs::users/34');

A URL with product as the first segment, and anything in the second will be mapped to the \App\Controllers\Catalog class and the productLookup() method:

<?php

$routes->get('product/(:segment)', 'Catalog::productLookup');

A URL with product as the first segment, and a number in the second will be mapped to the \App\Controllers\Catalog class and the productLookupByID() method passing in the match as a variable to the method:

<?php

$routes->get('product/(:num)', 'Catalog::productLookupByID/$1');

HTTP verb Routes

You can use any standard HTTP verb (GET, POST, PUT, DELETE, OPTIONS, etc):

<?php

$routes->post('products', 'Product::feature');
$routes->put('products/1', 'Product::feature');
$routes->delete('products/1', 'Product::feature');

You can supply multiple verbs that a route should match by passing them in as an array to the match() method:

<?php

$routes->match(['get', 'put'], 'products', 'Product::feature');

Specifying Route Handlers

Controller’s Namespace

When you specify a controller and method name as a string, if a controller is written without a leading \, the Default Namespace will be prepended:

<?php

// Routes to \App\Controllers\Api\Users::update()
$routes->post('api/users', 'Api\Users::update');

If you put \ at the beginning, it is treated as a fully qualified class name:

<?php

// Routes to \Acme\Blog\Controllers\Home::list()
$routes->get('blog', '\Acme\Blog\Controllers\Home::list');

You can also specify the namespace with the namespace option:

<?php

// Routes to \Admin\Users::index()
$routes->get('admin/users', 'Users::index', ['namespace' => 'Admin']);

See Assigning Namespace for details.

Array Callable Syntax

New in version 4.2.0.

Since v4.2.0, you can use array callable syntax to specify the controller:

$routes->get('/', [\App\Controllers\Home::class, 'index']);

Or using use keyword:

use App\Controllers\Home;

$routes->get('/', [Home::class, 'index']);

If you forget to add use App\Controllers\Home;, the controller classname is interpreted as Config\Home, not App\Controllers\Home because app/Config/Routes.php has namespace Config; at the top.

Note

When you use Array Callable Syntax, the classname is always interpreted as a fully qualified classname. So Default Namespace and namespace option have no effect.

Array Callable Syntax and Placeholders

If there are placeholders, it will automatically set the parameters in the specified order:

use App\Controllers\Product;

$routes->get('product/(:num)/(:num)', [Product::class, 'index']);

// The above code is the same as the following:
$routes->get('product/(:num)/(:num)', 'Product::index/$1/$2');

But the auto-configured parameters may not be correct if you use regular expressions in routes. In such a case, you can specify the parameters manually:

use App\Controllers\Product;

$routes->get('product/(:num)/(:num)', [[Product::class, 'index'], '$2/$1']);

// The above code is the same as the following:
$routes->get('product/(:num)/(:num)', 'Product::index/$2/$1');

Using Closures

You can use an anonymous function, or Closure, as the destination that a route maps to. This function will be executed when the user visits that URI. This is handy for quickly executing small tasks, or even just showing a simple view:

<?php

use App\Libraries\RSSFeeder;

$routes->get('feed', static function () {
    $rss = new RSSFeeder();

    return $rss->feed('general');
});

Specifying Route Paths

Placeholders

A typical route might look something like this:

<?php

$routes->get('product/(:num)', 'Catalog::productLookup');

In a route, the first parameter contains the URI to be matched, while the second parameter contains the destination it should be routed to. In the above example, if the literal word “product” is found in the first segment of the URL path, and a number is found in the second segment, the Catalog class and the productLookup method are used instead.

Placeholders are simply strings that represent a Regular Expression pattern. During the routing process, these placeholders are replaced with the value of the Regular Expression. They are primarily used for readability.

The following placeholders are available for you to use in your routes:

Placeholders

Description

(:any)

will match all characters from that point to the end of the URI. This may include multiple URI segments.

(:segment)

will match any character except for a forward slash (/) restricting the result to a single segment.

(:num)

will match any integer.

(:alpha)

will match any string of alphabetic characters

(:alphanum)

will match any string of alphabetic characters or integers, or any combination of the two.

(:hash)

is the same as (:segment), but can be used to easily see which routes use hashed ids.

Note

{locale} cannot be used as a placeholder or other part of the route, as it is reserved for use in localization.

The Behavior of (:any)

Note that a single (:any) will match multiple segments in the URL if present.

For example the route:

<?php

$routes->get('product/(:any)', 'Catalog::productLookup/$1');

will match product/123, product/123/456, product/123/456/789 and so on.

In the above example, if the $1 placeholder contains a slash (/), it will still be split into multiple parameters when passed to Catalog::productLookup().

The implementation in the Controller should take into account the maximum parameters:

<?php

namespace App\Controllers;

class Catalog extends BaseController
{
    public function productLookup($seg1 = false, $seg2 = false, $seg3 = false)
    {
        echo $seg1; // Will be 123 in all examples
        echo $seg2; // false in first, 456 in second and third example
        echo $seg3; // false in first and second, 789 in third
    }
}

Or you can use variable-length argument lists:

<?php

namespace App\Controllers;

class Catalog extends BaseController
{
    public function productLookup(...$params)
    {
        echo $params[0] ?? null; // Will be 123 in all examples
        echo $params[1] ?? null; // null in first, 456 in second and third example
        echo $params[2] ?? null; // null in first and second, 789 in third
    }
}

Important

Do not put any placeholder after (:any). Because the number of parameters passed to the controller method may change.

If matching multiple segments is not the intended behavior, (:segment) should be used when defining the routes. With the examples URLs from above:

<?php

$routes->get('product/(:segment)', 'Catalog::productLookup/$1');

will only match product/123 and generate 404 errors for other example.

Custom Placeholders

You can create your own placeholders that can be used in your routes file to fully customize the experience and readability.

You add new placeholders with the addPlaceholder() method. The first parameter is the string to be used as the placeholder. The second parameter is the Regular Expression pattern it should be replaced with. This must be called before you add the route:

<?php

$routes->addPlaceholder('uuid', '[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}');
$routes->get('users/(:uuid)', 'Users::show/$1');

Regular Expressions

If you prefer you can use regular expressions to define your routing rules. Any valid regular expression is allowed, as are back-references.

Important

Note: If you use back-references you must use the dollar syntax rather than the double backslash syntax. A typical RegEx route might look something like this:

<?php

$routes->get('products/([a-z]+)/(\d+)', 'Products::show/$1/id_$2');

In the above example, a URI similar to products/shirts/123 would instead call the show() method of the Products controller class, with the original first and second segment passed as arguments to it.

With regular expressions, you can also catch a segment containing a forward slash (/), which would usually represent the delimiter between multiple segments.

For example, if a user accesses a password protected area of your web application and you wish to be able to redirect them back to the same page after they log in, you may find this example useful:

<?php

$routes->get('login/(.+)', 'Auth::login/$1');

In the above example, if the $1 placeholder contains a slash (/), it will still be split into multiple parameters when passed to Auth::login().

For those of you who don’t know regular expressions and want to learn more about them, regular-expressions.info might be a good starting point.

Note

You can also mix and match placeholders with regular expressions.

View Routes

New in version 4.3.0.

If you just want to render a view out that has no logic associated with it, you can use the view() method. This is always treated as GET request. This method accepts the name of the view to load as the second parameter.

<?php

// Displays the view in /app/Views/pages/about.php
$routes->view('about', 'pages/about');

If you use placeholders within your route, you can access them within the view in a special variable, $segments. They are available as an array, indexed in the order they appear in the route.

<?php

// Displays the view in /app/Views/map.php
$routes->view('map/(:segment)/(:segment)', 'map');

// Within the view, you can access the segments with
// $segments[0] and $segments[1] respectively.

Redirecting Routes

Any site that lives long enough is bound to have pages that move. You can specify routes that should redirect to other routes with the addRedirect() method. The first parameter is the URI pattern for the old route. The second parameter is either the new URI to redirect to, or the name of a named route. The third parameter is the HTTP status code that should be sent along with the redirect. The default value is 302 which is a temporary redirect and is recommended in most cases:

<?php

$routes->get('users/profile', 'Users::profile', ['as' => 'profile']);

// Redirect to a named route
$routes->addRedirect('users/about', 'profile');
// Redirect to a URI
$routes->addRedirect('users/about', 'users/profile');

// Redirect with placeholder
$routes->get('post/(:num)/comment/(:num)', 'PostsComments::index', ['as' => 'post.comment']);

// Redirect to a URI
$routes->addRedirect('article/(:num)/(:num)', 'post/$1/comment/$2');
// Redirect to a named route
$routes->addRedirect('article/(:num)/(:num)', 'post.comment');

Note

Since v4.2.0, addRedirect() can use placeholders.

If a redirect route is matched during a page load, the user will be immediately redirected to the new page before a controller can be loaded.

Environment Restrictions

You can create a set of routes that will only be viewable in a certain environment. This allows you to create tools that only the developer can use on their local machines that are not reachable on testing or production servers. This can be done with the environment() method. The first parameter is the name of the environment. Any routes defined within this closure are only accessible from the given environment:

<?php

$routes->environment('development', static function ($routes) {
    $routes->get('builder', 'Tools\Builder::index');
});

Routes with any HTTP verbs

Important

This method exists only for backward compatibility. Do not use it in new projects. Even if you are already using it, we recommend that you use another, more appropriate method.

Warning

While the add() method seems to be convenient, it is recommended to always use the HTTP-verb-based routes, described above, as it is more secure. If you use the CSRF protection, it does not protect GET requests. If the URI specified in the add() method is accessible by the GET method, the CSRF protection will not work.

It is possible to define a route with any HTTP verbs. You can use the add() method:

<?php

$routes->add('products', 'Product::feature');

Note

Using the HTTP-verb-based routes will also provide a slight performance increase, since only routes that match the current request method are stored, resulting in fewer routes to scan through when trying to find a match.

Mapping Multiple Routes

Important

This method exists only for backward compatibility. Do not use it in new projects. Even if you are already using it, we recommend that you use another, more appropriate method.

Warning

The map() method is not recommended as well as add() because it calls add() internally.

While the add() method is simple to use, it is often handier to work with multiple routes at once, using the map() method. Instead of calling the add() method for each route that you need to add, you can define an array of routes and then pass it as the first parameter to the map() method:

<?php

$multipleRoutes = [
    'product/(:num)'      => 'Catalog::productLookupById',
    'product/(:alphanum)' => 'Catalog::productLookupByName',
];

$routes->map($multipleRoutes);

Command-Line Only Routes

Note

It is recommended to use Spark Commands for CLI scripts instead of calling controllers via CLI. See the Creating Spark Commands page for detailed information.

Any route created by any of the HTTP-verb-based route methods will also be inaccessible from the CLI, but routes created by the add() method will still be available from the command line.

You can create routes that work only from the command-line, and are inaccessible from the web browser, with the cli() method:

<?php

$routes->cli('migrate', 'App\Database::migrate');

Warning

If you enable Auto Routing (Legacy) and place the command file in app/Controllers, anyone could access the command with the help of Auto Routing (Legacy) via HTTP.

Global Options

All of the methods for creating a route (get(), post(), resource() etc) can take an array of options that can modify the generated routes, or further restrict them. The $options array is always the last parameter:

<?php

$routes->add('from', 'to', $options);
$routes->get('from', 'to', $options);
$routes->post('from', 'to', $options);
$routes->put('from', 'to', $options);
$routes->head('from', 'to', $options);
$routes->options('from', 'to', $options);
$routes->delete('from', 'to', $options);
$routes->patch('from', 'to', $options);
$routes->match(['get', 'put'], 'from', 'to', $options);
$routes->resource('photos', $options);
$routes->map($array, $options);
$routes->group('name', $options, static function () {});

Applying Filters

You can alter the behavior of specific routes by supplying filters to run before or after the controller. This is especially handy during authentication or api logging. The value for the filter can be a string or an array of strings:

  • matching the aliases defined in app/Config/Filters.php.

  • filter classnames

See Controller Filters for more information on setting up filters.

Warning

If you set filters to routes in app/Config/Routes.php (not in app/Config/Filters.php), it is recommended to disable Auto Routing (Legacy). When Auto Routing (Legacy) is enabled, it may be possible that a controller can be accessed via a different URL than the configured route, in which case the filter you specified to the route will not be applied. See Use Defined Routes Only to disable auto-routing.

Alias Filter

You specify an alias defined in app/Config/Filters.php for the filter value:

<?php

$routes->get('admin', ' AdminController::index', ['filter' => 'admin-auth']);

You may also supply arguments to be passed to the alias filter’s before() and after() methods:

<?php

$routes->post('users/delete/(:segment)', 'AdminController::index', ['filter' => 'admin-auth:dual,noreturn']);

Classname Filter

New in version 4.1.5.

You specify a filter classname for the filter value:

<?php

$routes->get('admin', ' AdminController::index', ['filter' => \App\Filters\SomeFilter::class]);

Multiple Filters

New in version 4.1.5.

Important

Multiple filters is disabled by default. Because it breaks backward compatibility. If you want to use it, you need to configure. See Multiple Filters for a Route for the details.

You specify an array for the filter value:

<?php

$routes->get('admin', ' AdminController::index', ['filter' => ['admin-auth', \App\Filters\SomeFilter::class]]);
Filter Arguments

Additional arguments may be passed to a filter:

<?php

$routes->add('users/delete/(:segment)', 'AdminController::index', ['filter' => 'admin-auth:dual,noreturn']);

In this example, the array ['dual', 'noreturn'] will be passed in $arguments to the filter’s before() and after() implementation methods.

Assigning Namespace

While a Default Namespace will be prepended to the generated controllers, you can also specify a different namespace to be used in any options array, with the namespace option. The value should be the namespace you want modified:

<?php

// Routes to \Admin\Users::index()
$routes->get('admin/users', 'Users::index', ['namespace' => 'Admin']);

The new namespace is only applied during that call for any methods that create a single route, like get, post, etc. For any methods that create multiple routes, the new namespace is attached to all routes generated by that function or, in the case of group(), all routes generated while in the closure.

Limit to Hostname

You can restrict groups of routes to function only in certain domain or sub-domains of your application by passing the “hostname” option along with the desired domain to allow it on as part of the options array:

<?php

$routes->get('from', 'to', ['hostname' => 'accounts.example.com']);

This example would only allow the specified hosts to work if the domain exactly matched accounts.example.com. It would not work under the main site at example.com.

Limit to Subdomains

When the subdomain option is present, the system will restrict the routes to only be available on that sub-domain. The route will only be matched if the subdomain is the one the application is being viewed through:

<?php

// Limit to media.example.com
$routes->get('from', 'to', ['subdomain' => 'media']);

You can restrict it to any subdomain by setting the value to an asterisk, (*). If you are viewing from a URL that does not have any subdomain present, this will not be matched:

<?php

// Limit to any sub-domain
$routes->get('from', 'to', ['subdomain' => '*']);

Important

The system is not perfect and should be tested for your specific domain before being used in production. Most domains should work fine but some edge case ones, especially with a period in the domain itself (not used to separate suffixes or www) can potentially lead to false positives.

Offsetting the Matched Parameters

You can offset the matched parameters in your route by any numeric value with the offset option, with the value being the number of segments to offset.

This can be beneficial when developing APIs with the first URI segment being the version number. It can also be used when the first parameter is a language string:

<?php

$routes->get('users/(:num)', 'users/show/$1', ['offset' => 1]);

// Creates:
$routes['users/(:num)'] = 'users/show/$2';

Reverse Routing

Reverse routing allows you to define the controller and method, as well as any parameters, that a link should go to, and have the router lookup the current route to it. This allows route definitions to change without you having to update your application code. This is typically used within views to create links.

For example, if you have a route to a photo gallery that you want to link to, you can use the url_to() helper function to get the route that should be used. The first parameter is the fully qualified Controller and method, separated by a double colon (::), much like you would use when writing the initial route itself. Any parameters that should be passed to the route are passed in next:

<?php

// The route is defined as:
$routes->get('users/(:num)/gallery/(:num)', 'Galleries::showUserGallery/$1/$2');

?>

<!-- Generate the URI to link to user ID 15, gallery 12: -->
<a href="<?= url_to('Galleries::showUserGallery', 15, 12) ?>">View Gallery</a>
<!-- Result: 'http://example.com/users/15/gallery/12' -->

Named Routes

You can name routes to make your application less fragile. This applies a name to a route that can be called later, and even if the route definition changes, all of the links in your application built with url_to() will still work without you having to make any changes. A route is named by passing in the as option with the name of the route:

<?php

// The route is defined as:
$routes->get('users/(:num)/gallery/(:num)', 'Galleries::showUserGallery/$1/$2', ['as' => 'user_gallery']);

?>

<!-- Generate the URI to link to user ID 15, gallery 12: -->
<a href="<?= url_to('user_gallery', 15, 12) ?>">View Gallery</a>
<!-- Result: 'http://example.com/users/15/gallery/12' -->

This has the added benefit of making the views more readable, too.

Grouping Routes

You can group your routes under a common name with the group() method. The group name becomes a segment that appears prior to the routes defined inside of the group. This allows you to reduce the typing needed to build out an extensive set of routes that all share the opening string, like when building an admin area:

<?php

$routes->group('admin', static function ($routes) {
    $routes->get('users', 'Admin\Users::index');
    $routes->get('blog', 'Admin\Blog::index');
});

This would prefix the users and blog URIs with admin, handling URLs like admin/users and admin/blog.

Setting Namespace

If you need to assign options to a group, like a Assigning Namespace, do it before the callback:

<?php

$routes->group('api', ['namespace' => 'App\API\v1'], static function ($routes) {
    $routes->resource('users');
});

This would handle a resource route to the App\API\v1\Users controller with the api/users URI.

Setting Filters

You can also use a specific filter for a group of routes. This will always run the filter before or after the controller. This is especially handy during authentication or api logging:

<?php

$routes->group('api', ['filter' => 'api-auth'], static function ($routes) {
    $routes->resource('users');
});

The value for the filter must match one of the aliases defined within app/Config/Filters.php.

Setting Other Options

At some point, you may want to group routes for the purpose of applying filters or other route config options like namespace, subdomain, etc. Without necessarily needing to add a prefix to the group, you can pass an empty string in place of the prefix and the routes in the group will be routed as though the group never existed but with the given route config options:

<?php

$routes->group('', ['namespace' => 'Myth\Auth\Controllers'], static function ($routes) {
    $routes->get('login', 'AuthController::login', ['as' => 'login']);
    $routes->post('login', 'AuthController::attemptLogin');
    $routes->get('logout', 'AuthController::logout');
});

Nesting Groups

It is possible to nest groups within groups for finer organization if you need it:

<?php

$routes->group('admin', static function ($routes) {
    $routes->group('users', static function ($routes) {
        $routes->get('list', 'Admin\Users::list');
    });
});

This would handle the URL at admin/users/list.

Note

Options passed to the outer group() (for example namespace and filter) are not merged with the inner group() options.

Route Priority

Routes are registered in the routing table in the order in which they are defined. This means that when a URI is accessed, the first matching route will be executed.

Warning

If a route path is defined more than once with different handlers, only the first defined route is registered.

You can check registered routes in the routing table by running the spark routes command.

Changing Route Priority

When working with modules, it can be a problem if the routes in the application contain wildcards. Then the module routes will not be processed correctly. You can solve this problem by lowering the priority of route processing using the priority option. The parameter accepts positive integers and zero. The higher the number specified in the priority, the lower route priority in the processing queue:

<?php

// First you need to enable processing of the routes queue by priority.
$routes->setPrioritize();

// Config\Routes
$routes->get('(.*)', 'Posts::index', ['priority' => 1]);

// Modules\Acme\Config\Routes
$routes->get('admin', 'Admin::index');

// The "admin" route will now be processed before the wildcard route.

To disable this functionality, you must call the method with the parameter false:

<?php

$routes->setPrioritize(false);

Note

By default, all routes have a priority of 0. Negative integers will be cast to the absolute value.

Routes Configuration Options

The RoutesCollection class provides several options that affect all routes, and can be modified to meet your application’s needs. These options are available in app/Config/Routing.php.

Note

The config file app/Config/Routing.php has been added since v4.4.0. In previous versions, the setter methods were used in app/Config/Routes.php to change settings.

Default Namespace

When matching a controller to a route, the router will add the default namespace value to the front of the controller specified by the route. By default, this value is App\Controllers.

If you set the value empty string (''), it leaves each route to specify the fully namespaced controller:

<?php

// In app/Config/Routing.php
use CodeIgniter\Config\Routing as BaseRouting;

// ...
class Routing extends BaseRouting
{
    // ...
    public string $defaultNamespace = '';
    // ...
}

// In app/Config/Routes.php
// Controller is \Users
$routes->get('users', 'Users::index');

// Controller is \Admin\Users
$routes->get('users', 'Admin\Users::index');

If your controllers are not explicitly namespaced, there is no need to change this. If you namespace your controllers, then you can change this value to save typing:

<?php

// This can be overridden in app/Config/Routes.php
$routes->setDefaultNamespace('App');

// Controller is \App\Users
$routes->get('users', 'Users::index');

// Controller is \App\Admin\Users
$routes->get('users', 'Admin\Users::index');

Translate URI Dashes

This option enables you to automatically replace dashes (-) with underscores in the controller and method URI segments when used in Auto Routing, thus saving you additional route entries if you need to do that. This is required because the dash isn’t a valid class or method name character and would cause a fatal error if you try to use it:

<?php

// In app/Config/Routing.php
use CodeIgniter\Config\Routing as BaseRouting;

// ...
class Routing extends BaseRouting
{
    // ...
    public bool $translateURIDashes = true;
    // ...
}

// This can be overridden in app/Config/Routes.php
$routes->setTranslateURIDashes(true);

Note

When using Auto Routing (Improved), prior to v4.4.0, if $translateURIDashes is true, two URIs correspond to a single controller method, one URI for dashes (e.g., foo-bar) and one URI for underscores (e.g., foo_bar). This was incorrect behavior. Since v4.4.0, the URI for underscores (foo_bar) is not accessible.

Use Defined Routes Only

Since v4.2.0, the auto-routing is disabled by default.

When no defined route is found that matches the URI, the system will attempt to match that URI against the controllers and methods when Auto Routing is enabled.

You can disable this automatic matching, and restrict routes to only those defined by you, by setting the $autoRoute property to false:

<?php

// In app/Config/Routing.php
use CodeIgniter\Config\Routing as BaseRouting;

// ...
class Routing extends BaseRouting
{
    // ...
    public bool $autoRoute = false;
    // ...
}

// This can be overridden in app/Config/Routes.php
$routes->setAutoRoute(false);

Warning

If you use the CSRF protection, it does not protect GET requests. If the URI is accessible by the GET method, the CSRF protection will not work.

404 Override

When a page is not found that matches the current URI, the system will show a generic 404 view. You can change what happens by specifying an action to happen with the set404Override() method. The value can be either a valid class/method pair, just like you would show in any route, or a Closure:

<?php

// In app/Config/Routing.php
use CodeIgniter\Config\Routing as BaseRouting;

// ...
class Routing extends BaseRouting
{
    // ...
    public ?string $override404 = 'App\Errors::show404';
    // ...
}

// In app/Config/Routes.php
// Would execute the show404 method of the App\Errors class
$routes->set404Override('App\Errors::show404');

// Will display a custom view
$routes->set404Override(static function () {
    echo view('my_errors/not_found.html');
});

Using the $override404 property within the routing config file, you can use closures. Defining the override in the Routing file is restricted to class/method pairs.

Note

The set404Override() method does not change the Response status code to 404. If you don’t set the status code in the controller you set, the default status code 200 will be returned. See CodeIgniter\HTTP\Response::setStatusCode() for information on how to set the status code.

Route Processing by Priority

Enables or disables processing of the routes queue by priority. Lowering the priority is defined in the route option. Disabled by default. This functionality affects all routes. For an example use of lowering the priority see Route Priority:

<?php

// In app/Config/Routing.php
use CodeIgniter\Config\Routing as BaseRouting;

// ...
class Routing extends BaseRouting
{
    // ...
    public bool $prioritize = true;
    // ...
}

// In app/Config/Routes.php
// to enable
$routes->setPrioritize();

// to disable
$routes->setPrioritize(false);

Auto Routing (Improved)

New in version 4.2.0.

Since v4.2.0, the new more secure Auto Routing has been introduced.

Note

If you are familiar with Auto Routing, which was enabled by default from CodeIgniter 3 through 4.1.x, you can see the differences in ChangeLog v4.2.0.

When no defined route is found that matches the URI, the system will attempt to match that URI against the controllers and methods when Auto Routing is enabled.

Important

For security reasons, if a controller is used in the defined routes, Auto Routing (Improved) does not route to the controller.

Auto Routing can automatically route HTTP requests based on conventions and execute the corresponding controller methods.

Note

Auto Routing (Improved) is disabled by default. To use it, see below.

Enable Auto Routing

To use it, you need to change the setting $autoRoute option to true in app/Config/Routing.php:

public bool $autoRoute = true;

And you need to change the property $autoRoutesImproved to true in app/Config/Feature.php:

public bool $autoRoutesImproved = true;

URI Segments

The segments in the URL, in following with the Model-View-Controller approach, usually represent:

example.com/class/method/ID
  1. The first segment represents the controller class that should be invoked.

  2. The second segment represents the class method that should be called.

  3. The third, and any additional segments, represent the ID and any variables that will be passed to the controller.

Consider this URI:

example.com/index.php/helloworld/hello/1

In the above example, when you send a HTTP request with GET method, Auto Routing would attempt to find a controller named App\Controllers\Helloworld and executes getHello() method with passing '1' as the first argument.

Note

A controller method that will be executed by Auto Routing (Improved) needs HTTP verb (get, post, put, etc.) prefix like getIndex(), postCreate().

See Auto Routing in Controllers for more info.

Configuration Options

These options are available in the app/Config/Routing.php file.

Default Controller

For Site Root URI

When a user visits the root of your site (i.e., example.com) the controller to use is determined by the value set to the $defaultController property, unless a route exists for it explicitly.

The default value for this is Home which matches the controller at app/Controllers/Home.php:

public string $defaultController = 'Home';
For Directory URI

The default controller is also used when no matching route has been found, and the URI would point to a directory in the controllers directory. For example, if the user visits example.com/admin, if a controller was found at app/Controllers/Admin/Home.php, it would be used.

Important

You cannot access the default controller with the URI of the controller name. When the default controller is Home, you can access example.com/, but if you access example.com/home, it will be not found.

See Auto Routing in Controllers for more info.

Default Method

This works similar to the default controller setting, but is used to determine the default method that is used when a controller is found that matches the URI, but no segment exists for the method. The default value is index.

In this example, if the user were to visit example.com/products, and a Products controller existed, the Products::getListAll() method would be executed:

public string $defaultMethod = 'listAll';

Important

You cannot access the controller with the URI of the default method name. In the example above, you can access example.com/products, but if you access example.com/products/listall, it will be not found.

Module Routing

New in version 4.4.0.

You can use auto routing even if you use Code Modules and place the controllers in a different namespace.

To route to a module, the $moduleRoutes property in app/Config/Routing.php must be set:

public array $moduleRoutes = [
    'blog' => 'Acme\Blog\Controllers',
];

The key is the first URI segment for the module, and the value is the controller namespace. In the above configuration, http://localhost:8080/blog/foo/bar will be routed to Acme\Blog\Controllers\Foo::getBar().

Note

If you define $moduleRoutes, the routing for the module takes precedence. In the above example, even if you have the App\Controllers\Blog controller, http://localhost:8080/blog will be routed to the default controller Acme\Blog\Controllers\Home.

Auto Routing (Legacy)

Important

This feature exists only for backward compatibility. Do not use it in new projects. Even if you are already using it, we recommend that you use the Auto Routing (Improved) instead.

Auto Routing (Legacy) is a routing system from CodeIgniter 3. It can automatically route HTTP requests based on conventions and execute the corresponding controller methods.

It is recommended that all routes are defined in the app/Config/Routes.php file, or to use Auto Routing (Improved),

Warning

To prevent misconfiguration and miscoding, we recommend that you do not use Auto Routing (Legacy) feature. It is easy to create vulnerable apps where controller filters or CSRF protection are bypassed.

Important

Auto Routing (Legacy) routes a HTTP request with any HTTP method to a controller method.

Enable Auto Routing (Legacy)

Since v4.2.0, the auto-routing is disabled by default.

To use it, you need to change the setting $autoRoute option to true in app/Config/Routing.php:

public bool $autoRoute = true;

And set the property $autoRoutesImproved to false in app/Config/Feature.php:

public bool $autoRoutesImproved = false;

URI Segments (Legacy)

The segments in the URL, in following with the Model-View-Controller approach, usually represent:

example.com/class/method/ID
  1. The first segment represents the controller class that should be invoked.

  2. The second segment represents the class method that should be called.

  3. The third, and any additional segments, represent the ID and any variables that will be passed to the controller.

Consider this URI:

example.com/index.php/helloworld/index/1

In the above example, CodeIgniter would attempt to find a controller named Helloworld.php and executes index() method with passing '1' as the first argument.

See Auto Routing (Legacy) in Controllers for more info.

Configuration Options (Legacy)

These options are available in the app/Config/Routing.php file.

Default Controller (Legacy)

For Site Root URI (Legacy)

When a user visits the root of your site (i.e., example.com) the controller to use is determined by the value set to the $defaultController property, unless a route exists for it explicitly.

The default value for this is Home which matches the controller at app/Controllers/Home.php:

public string $defaultController = 'Home';
For Directory URI (Legacy)

The default controller is also used when no matching route has been found, and the URI would point to a directory in the controllers directory. For example, if the user visits example.com/admin, if a controller was found at app/Controllers/Admin/Home.php, it would be used.

See Auto Routing (Legacy) in Controllers for more info.

Default Method (Legacy)

This works similar to the default controller setting, but is used to determine the default method that is used when a controller is found that matches the URI, but no segment exists for the method. The default value is index.

In this example, if the user were to visit example.com/products, and a Products controller existed, the Products::listAll() method would be executed:

public string $defaultMethod = 'listAll';

Confirming Routes

CodeIgniter has the following command to display all routes.

spark routes

Displays all routes and filters:

php spark routes

The output is like the following:

+---------+---------+---------------+-------------------------------+----------------+---------------+
| Method  | Route   | Name          | Handler                       | Before Filters | After Filters |
+---------+---------+---------------+-------------------------------+----------------+---------------+
| GET     | /       | »             | \App\Controllers\Home::index  |                | toolbar       |
| GET     | feed    | »             | (Closure)                     |                | toolbar       |
+---------+---------+---------------+-------------------------------+----------------+---------------+

The Method column shows the HTTP method that the route is listening for.

The Route column shows the route path to match. The route of a defined route is expressed as a regular expression.

Since v4.3.0, the Name column shows the route name. » indicates the name is the same as the route path.

Important

The system is not perfect. For routes containing regular expression patterns like ([^/]+) or {locale}, the Filters displayed might not be correct (if you set complicated URI pattern for the filters in app/Config/Filters.php), or it is displayed as <unknown>.

The spark filter:check command can be used to check for 100% accurate filters.

Auto Routing (Improved)

When you use Auto Routing (Improved), the output is like the following:

+-----------+-------------------------+---------------+-----------------------------------+----------------+---------------+
| Method    | Route                   | Name          | Handler                           | Before Filters | After Filters |
+-----------+-------------------------+---------------+-----------------------------------+----------------+---------------+
| GET(auto) | product/list/../..[/..] |               | \App\Controllers\Product::getList |                | toolbar       |
+-----------+-------------------------+---------------+-----------------------------------+----------------+---------------+

The Method will be like GET(auto).

/.. in the Route column indicates one segment. [/..] indicates it is optional.

Note

When auto-routing is enabled and you have the route home, it can be also accessed by Home, or maybe by hOme, hoMe, HOME, etc. but the command will show only home.

If you see a route starting with x like the following, it indicates an invalid route that won’t be routed, but the controller has a public method for routing.

+-----------+----------------+------+-------------------------------------+----------------+---------------+
| Method    | Route          | Name | Handler                             | Before Filters | After Filters |
+-----------+----------------+------+-------------------------------------+----------------+---------------+
| GET(auto) | x home/foo     |      | \App\Controllers\Home::getFoo       | <unknown>      | <unknown>     |
+-----------+----------------+------+-------------------------------------+----------------+---------------+

The above example shows you have the \App\Controllers\Home::getFoo() method, but it is not routed because it is the default controller (Home by default) and the default controller name must be omitted in the URI. You should delete the getFoo() method.

Note

Prior to v4.3.4, the invalid route is displayed as a normal route due to a bug.

Auto Routing (Legacy)

When you use Auto Routing (Legacy), the output is like the following:

+--------+--------------------+---------------+-----------------------------------+----------------+---------------+
| Method | Route              | Name          | Handler                           | Before Filters | After Filters |
+--------+--------------------+---------------+-----------------------------------+----------------+---------------+
| auto   | product/list[/...] |               | \App\Controllers\Product::getList |                | toolbar       |
+--------+--------------------+---------------+-----------------------------------+----------------+---------------+

The Method will be auto.

[/...] in the Route column indicates any number of segments.

Note

When auto-routing is enabled and you have the route home, it can be also accessed by Home, or maybe by hOme, hoMe, HOME, etc. but the command will show only home.

Sort by Handler

New in version 4.3.0.

You can sort the routes by Handler:

php spark routes -h

Specify Host

New in version 4.4.0.

You can specify the host in the request URL with the --host option:

php spark routes --host accounts.example.com