This document is for CakePHP's development version, which can be significantly different from previous releases.
You may want to read current stable release documentation instead.

Plugins

CakePHP allows you to set up a combination of controllers, models, and views and release them as a pre-packaged application plugin that others can use in their CakePHP applications. If you’ve created great user management, a simple blog, or web service adapters in one of your applications, why not package it as a CakePHP plugin? This way you can reuse it in your other applications, and share with the community!

A CakePHP plugin is separate from the host application itself and generally provides some well-defined functionality that can be packaged up neatly, and reused with little effort in other applications. The application and the plugin operate in their own respective spaces, but share the application’s configuration data (for example, database connections, email transports)

Plugin should define their own top-level namespace. For example: DebugKit. By convention, plugins use their package name as their namespace. If you’d like to use a different namespace, you can configure the plugin namespace, when plugins are loaded.

Installing a Plugin With Composer

Many plugins are available on Packagist and can be installed with Composer. To install DebugKit, you would do the following:

php composer.phar require cakephp/debug_kit

This would install the latest version of DebugKit and update your composer.json, composer.lock file, update vendor/cakephp-plugins.php, and update your autoloader.

Manually Installing a Plugin

If the plugin you want to install is not available on packagist.org, you can clone or copy the plugin code into your plugins directory. Assuming you want to install a plugin named ‘ContactManager’, you should have a folder in plugins named ‘ContactManager’. In this directory are the plugin’s src, tests and any other directories.

Manually Autoloading Plugin Classes

If you install your plugins via composer or bake you shouldn’t need to configure class autoloading for your plugins.

If we were installing a plugin named MyPlugin manually you would need to modify your application’s composer.json file to contain the following information:

{
    "autoload": {
        "psr-4": {
            "MyPlugin\\": "plugins/MyPlugin/src/"
        }
    },
    "autoload-dev": {
        "psr-4": {
            "MyPlugin\\Test\\": "plugins/MyPlugin/tests/"
        }
    }
}

If you are using vendor namespaces for your plugins, the namespace to path mapping should resemble the following:

{
    "autoload": {
        "psr-4": {
            "AcmeCorp\\Users\\": "plugins/AcmeCorp/Users/src/",
            "AcmeCorp\\Users\\Test\\": "plugins/AcmeCorp/Users/tests/"
        }
    }
}

Additionally, you will need to tell Composer to refresh its autoloading cache:

php composer.phar dumpautoload

Loading a Plugin

If you want to use a plugin’s routes, console commands, middlewares, event listeners, templates or webroot assets you will need to load the plugin. Plugins are loaded in your application’s bootstrap() function:

// In src/Application.php
use Cake\Http\BaseApplication;
use ContactManager\ContactManagerPlugin;

class Application extends BaseApplication {
    public function bootstrap()
    {
        parent::bootstrap();
        // Load the contact manager plugin by class name
        $this->addPlugin(ContactManagerPlugin::class);

        // Load a plugin with a vendor namespace by 'short name'
        $this->addPlugin('AcmeCorp/ContactManager');

        // Load a dev dependency that will not exist in production builds.
        $this->addOptionalPlugin('AcmeCorp/ContactManager');
    }
}

If you just want to use helpers, behaviors or components from a plugin you do not need to explicitly load a plugin yet it’s recommended to always do so.

There is also a handy shell command to enable the plugin. Execute the following line:

bin/cake plugin load ContactManager

This would update your application’s bootstrap method, or put the $this->addPlugin('ContactManager'); snippet in the bootstrap for you.

New in version 4.1.0: The addOptionalPlugin() method was added.

Plugin Hook Configuration

Plugins offer several hooks that allow a plugin to inject itself into the appropriate parts of your application. The hooks are:

  • bootstrap Used to load plugin default configuration files, define constants and other global functions.

  • routes Used to load routes for a plugin. Fired after application routes are loaded.

  • middleware Used to add plugin middleware to an application’s middleware queue.

  • console Used to add console commands to an application’s command collection.

When loading plugins you can configure which hooks are enabled. By default plugins without a Plugin Objects have all hooks disabled. New style plugins allow plugin authors to set defaults, which can be configured by you in your application:

// In Application::bootstrap()
use ContactManager\ContactManagerPlugin;

// Disable routes for the ContactManager plugin
$this->addPlugin(ContactManagerPlugin::class, ['routes' => false]);

You can configure hooks with array options, or the methods provided by plugin classes:

// In Application::bootstrap()
use ContactManager\ContactManagerPlugin;

// Use the disable/enable to configure hooks.
$plugin = new ContactManagerPlugin();

$plugin->disable('bootstrap');
$plugin->enable('routes');
$this->addPlugin($plugin);

Plugin objects also know their names and path information:

$plugin = new ContactManagerPlugin();

// Get the plugin name.
$name = $plugin->getName();

// Path to the plugin root, and other paths.
$path = $plugin->getPath();
$path = $plugin->getConfigPath();
$path = $plugin->getClassPath();

Using Plugin Classes

You can reference a plugin’s controllers, models, components, behaviors, and helpers by prefixing the name of the plugin.

For example, say you wanted to use the ContactManager plugin’s ContactInfoHelper to output formatted contact information in one of your views. In your controller, using addHelper() could look like this:

$this->viewBuilder()->addHelper('ContactManager.ContactInfo');

Note

This dot separated class name is referred to as plugin syntax.

You would then be able to access the ContactInfoHelper just like any other helper in your view, such as:

echo $this->ContactInfo->address($contact);

Plugins can use the models, components, behaviors and helpers provided by the application, or other plugins if necessary:

// Use an application component
$this->loadComponent('AppFlash');

// Use another plugin's behavior
$this->addBehavior('OtherPlugin.AuditLog');

Creating Your Own Plugins

As a working example, let’s begin to create the ContactManager plugin referenced above. To start out, we’ll set up our plugin’s basic directory structure. It should look like this:

/src
/plugins
    /ContactManager
        /config
        /src
            /ContactManagerPlugin.php
            /Controller
                /Component
            /Model
                /Table
                /Entity
                /Behavior
            /View
                /Helper
        /templates
            /layout
        /tests
            /TestCase
            /Fixture
        /webroot

Note the name of the plugin folder, ‘ContactManager’. It is important that this folder has the same name as the plugin.

Inside the plugin folder, you’ll notice it looks a lot like a CakePHP application, and that’s basically what it is. You don’t have to include any of the folders you are not using. Some plugins might only define a Component and a Behavior, and in that case they can completely omit the ‘templates’ directory.

A plugin can also have basically any of the other directories that your application can, such as Config, Console, webroot, etc.

Creating a Plugin Using Bake

The process of creating plugins can be greatly simplified by using bake.

In order to bake a plugin, use the following command:

bin/cake bake plugin ContactManager

Bake can be used to create classes in your plugin. For example to generate a plugin controller you could run:

bin/cake bake controller --plugin ContactManager Contacts

Please refer to the chapter Code Generation with Bake if you have any problems with using the command line. Be sure to re-generate your autoloader once you’ve created your plugin:

php composer.phar dumpautoload

Plugin Objects

Plugin Objects allow a plugin author to define set-up logic, define default hooks, load routes, middleware and console commands. Plugin objects live in src/Plugin.php. For our ContactManager plugin, our plugin class could look like:

namespace ContactManager;

use Cake\Core\BasePlugin;
use Cake\Core\ContainerInterface;
use Cake\Core\PluginApplicationInterface;
use Cake\Console\CommandCollection;
use Cake\Http\MiddlewareQueue;

class ContactManagerPlugin extends BasePlugin
{
    public function middleware(MiddlewareQueue $middleware): MiddlewareQueue
    {
        // Add middleware here.
        $middleware = parent::middleware($middleware);

        return $middleware;
    }

    public function console(CommandCollection $commands): CommandCollection
    {
        // Add console commands here.
        $commands = parent::console($commands);

        return $commands;
    }

    public function bootstrap(PluginApplicationInterface $app): void
    {
        // Add constants, load configuration defaults.
        // By default will load `config/bootstrap.php` in the plugin.
        parent::bootstrap($app);
    }

    public function routes($routes): void
    {
        // Add routes.
        // By default will load `config/routes.php` in the plugin.
        parent::routes($routes);
    }

    /**
     * Register application container services.
     *
     * @param \Cake\Core\ContainerInterface $container The Container to update.
     * @return void
     * @link https://book.cakephp.org/4/en/development/dependency-injection.html#dependency-injection
     */
    public function services(ContainerInterface $container): void
    {
        // Add your services here
    }
}

Plugin Routes

Plugins can provide routes files containing their routes. Each plugin can contain a config/routes.php file. This routes file can be loaded when the plugin is added, or in the application’s routes file. To create the ContactManager plugin routes, put the following into plugins/ContactManager/config/routes.php:

<?php
use Cake\Routing\Route\DashedRoute;

$routes->plugin(
    'ContactManager',
    ['path' => '/contact-manager'],
    function ($routes) {
        $routes->setRouteClass(DashedRoute::class);

        $routes->get('/contacts', ['controller' => 'Contacts']);
        $routes->get('/contacts/{id}', ['controller' => 'Contacts', 'action' => 'view']);
        $routes->put('/contacts/{id}', ['controller' => 'Contacts', 'action' => 'update']);
    }
);

The above will connect default routes for your plugin. You can customize this file with more specific routes later on.

Before you can access your controllers, you’ll need to ensure the plugin is loaded and the plugin routes are loaded. In your src/Application.php add the following:

$this->addPlugin('ContactManager', ['routes' => true]);

You can also load plugin routes in your application’s routes list. Doing this provides you more control on how plugin routes are loaded and allows you to wrap plugin routes in additional scopes or prefixes:

$routes->scope('/', function ($routes) {
    // Connect other routes.
    $routes->scope('/backend', function ($routes) {
        $routes->loadPlugin('ContactManager');
    });
});

The above would result in URLs like /backend/contact-manager/contacts.

Plugin Controllers

Controllers for our ContactManager plugin will be stored in plugins/ContactManager/src/Controller/. Since the main thing we’ll be doing is managing contacts, we’ll need a ContactsController for this plugin.

So, we place our new ContactsController in plugins/ContactManager/src/Controller and it looks like so:

// plugins/ContactManager/src/Controller/ContactsController.php
namespace ContactManager\Controller;

use ContactManager\Controller\AppController;

class ContactsController extends AppController
{
    public function index()
    {
        //...
    }
}

Also make the AppController if you don’t have one already:

// plugins/ContactManager/src/Controller/AppController.php
namespace ContactManager\Controller;

use App\Controller\AppController as BaseController;

class AppController extends BaseController
{
}

A plugin’s AppController can hold controller logic common to all controllers in a plugin but is not required if you don’t want to use one.

If you want to access what we’ve got going thus far, visit /contact-manager/contacts. You should get a “Missing Model” error because we don’t have a Contact model defined yet.

If your application includes the default routing CakePHP provides you will be able to access your plugin controllers using URLs like:

// Access the index route of a plugin controller.
/contact-manager/contacts

// Any action on a plugin controller.
/contact-manager/contacts/view/1

If your application defines routing prefixes, CakePHP’s default routing will also connect routes that use the following pattern:

/{prefix}/{plugin}/{controller}
/{prefix}/{plugin}/{controller}/{action}

See the section on Plugin Hook Configuration for information on how to load plugin specific route files.

For plugins you did not create with bake, you will also need to edit the composer.json file to add your plugin to the autoload classes, this can be done as per the documentation Manually Autoloading Plugin Classes.

Plugin Models

Models for the plugin are stored in plugins/ContactManager/src/Model. We’ve already defined a ContactsController for this plugin, so let’s create the table and entity for that controller:

// plugins/ContactManager/src/Model/Entity/Contact.php:
namespace ContactManager\Model\Entity;

use Cake\ORM\Entity;

class Contact extends Entity
{
}

// plugins/ContactManager/src/Model/Table/ContactsTable.php:
namespace ContactManager\Model\Table;

use Cake\ORM\Table;

class ContactsTable extends Table
{
}

If you need to reference a model within your plugin when building associations or defining entity classes, you need to include the plugin name with the class name, separated with a dot. For example:

// plugins/ContactManager/src/Model/Table/ContactsTable.php:
namespace ContactManager\Model\Table;

use Cake\ORM\Table;

class ContactsTable extends Table
{
    public function initialize(array $config): void
    {
        $this->hasMany('ContactManager.AltName');
    }
}

If you would prefer that the array keys for the association not have the plugin prefix on them, use the alternative syntax:

// plugins/ContactManager/src/Model/Table/ContactsTable.php:
namespace ContactManager\Model\Table;

use Cake\ORM\Table;

class ContactsTable extends Table
{
    public function initialize(array $config): void
    {
        $this->hasMany('AltName', [
            'className' => 'ContactManager.AltName',
        ]);
    }
}

You can use Cake\ORM\Locator\LocatorAwareTrait to load your plugin tables using the familiar plugin syntax:

// Controllers already use LocatorAwareTrait, so you don't need this.
use Cake\ORM\Locator\LocatorAwareTrait;

$contacts = $this->fetchTable('ContactManager.Contacts');

Plugin Templates

Views behave exactly as they do in normal applications. Just place them in the right folder inside of the plugins/[PluginName]/templates/ folder. For our ContactManager plugin, we’ll need a view for our ContactsController::index() action, so let’s include that as well:

// plugins/ContactManager/templates/Contacts/index.php:
<h1>Contacts</h1>
<p>Following is a sortable list of your contacts</p>
<!-- A sortable list of contacts would go here....-->

Plugins can provide their own layouts. To add plugin layouts, place your template files inside plugins/[PluginName]/templates/layout. To use a plugin layout in your controller you can do the following:

$this->viewBuilder()->setLayout('ContactManager.admin');

If the plugin prefix is omitted, the layout/view file will be located normally.

Note

For information on how to use elements from a plugin, look up Elements

Overriding Plugin Templates from Inside Your Application

You can override any plugin views from inside your app using special paths. If you have a plugin called ‘ContactManager’ you can override the template files of the plugin with application specific view logic by creating files using the following template templates/plugin/[Plugin]/[Controller]/[view].php. For the Contacts controller you could make the following file:

templates/plugin/ContactManager/Contacts/index.php

Creating this file would allow you to override plugins/ContactManager/templates/Contacts/index.php.

If your plugin is in a composer dependency (i.e. ‘Company/ContactManager’), the path to the ‘index’ view of the Contacts controller will be:

templates/plugin/TheVendor/ThePlugin/Custom/index.php

Creating this file would allow you to override vendor/thevendor/theplugin/templates/Custom/index.php.

If the plugin implements a routing prefix, you must include the routing prefix in your application template overrides. For example, if the ‘ContactManager’ plugin implemented an ‘Admin’ prefix the overriding path would be:

templates/plugin/ContactManager/Admin/ContactManager/index.php

Plugin Assets

A plugin’s web assets (but not PHP files) can be served through the plugin’s webroot directory, just like the main application’s assets:

/plugins/ContactManager/webroot/
                               css/
                               js/
                               img/
                               flash/
                               pdf/

You may put any type of file in any directory, just like a regular webroot.

Warning

Handling static assets (such as images, JavaScript and CSS files) through the Dispatcher is very inefficient. See Improve Your Application’s Performance for more information.

Linking to Assets in Plugins

You can use the plugin syntax when linking to plugin assets using the HtmlHelper’s script, image, or css methods:

// Generates a URL of /contact_manager/css/styles.css
echo $this->Html->css('ContactManager.styles');

// Generates a URL of /contact_manager/js/widget.js
echo $this->Html->script('ContactManager.widget');

// Generates a URL of /contact_manager/img/logo.jpg
echo $this->Html->image('ContactManager.logo');

Plugin assets are served using the AssetMiddleware middleware by default. This is only recommended for development. In production you should symlink plugin assets to improve performance.

If you are not using the helpers, you can prepend /plugin-name/ to the beginning of the URL for an asset within that plugin to serve it. Linking to ‘/contact_manager/js/some_file.js’ would serve the asset plugins/ContactManager/webroot/js/some_file.js.

Components, Helpers and Behaviors

A plugin can have Components, Helpers and Behaviors just like a CakePHP application. You can even create plugins that consist only of Components, Helpers or Behaviors which can be a great way to build reusable components that can be dropped into any project.

Building these components is exactly the same as building it within a regular application, with no special naming convention.

Referring to your component from inside or outside of your plugin requires only that you prefix the plugin name before the name of the component. For example:

// Component defined in 'ContactManager' plugin
namespace ContactManager\Controller\Component;

use Cake\Controller\Component;

class ExampleComponent extends Component
{
}

// Within your controllers
public function initialize(): void
{
    parent::initialize();
    $this->loadComponent('ContactManager.Example');
}

The same technique applies to Helpers and Behaviors.

Commands

Plugins can register their commands inside the console() hook. By default all shells and commands in the plugin are auto-discovered and added to the application’s command list. Plugin commands are prefixed with the plugin name. For example, the UserCommand provided by the ContactManager plugin would be registered as both contact_manager.user and user. The un-prefixed name will only be taken by a plugin if it is not used by the application, or another plugin.

You can customize the command names by defining each command in your plugin:

public function console($commands)
{
    // Create nested commands
    $commands->add('bake model', ModelCommand::class);
    $commands->add('bake controller', ControllerCommand::class);

    return $commands;
}

Testing your Plugin

If you are testing controllers or generating URLs, make sure your plugin connects routes tests/bootstrap.php.

For more information see testing plugins page.

Publishing your Plugin

CakePHP plugins should be published to the packagist. This way other people can use it as composer dependency. You can also propose your plugin to the awesome-cakephp list.

Choose a semantically meaningful name for the package name. This should ideally be prefixed with the dependency, in this case “cakephp” as the framework. The vendor name will usually be your GitHub username. Do not use the CakePHP namespace (cakephp) as this is reserved to CakePHP owned plugins. The convention is to use lowercase letters and dashes as separator.

So if you created a plugin “Logging” with your GitHub account “FooBar”, a good name would be foo-bar/cakephp-logging. And the CakePHP owned “Localized” plugin can be found under cakephp/localized respectively.

Plugin Map File

When installing plugins via Composer, you may notice that vendor/cakephp-plugins.php is created. This configuration file contains a map of plugin names and their paths on the filesystem. It makes it possible for plugins to be installed into the standard vendor directory which is outside of the normal search paths. The Plugin class will use this file to locate plugins when they are loaded with addPlugin(). You generally won’t need to edit this file by hand, as Composer and the plugin-installer package will manage it for you.

Manage Your Plugins using Mixer

Another way to discover and manage plugins into your CakePHP application is Mixer. It is a CakePHP plugin which helps you to install plugins from Packagist. It also helps you to manage your existing plugins.

Note

IMPORTANT: Do not use this in production environment.