And… action!

Our journey through the blog example is not only an educational journey, but also an active one. We now turn to the activities. We are already in the BlogController. You can find the class file at EXT:blog_example/Classes/BlogController.php.

In software development, there are different variants of controllers. In Extbase the controllers mostly exist as ActionController. This variant is characterized by short methods, which are responsible for the control of a single action, the so called Actions. Let’s have a deeper look at a shortened version of the BlogController. Please note that for brevity the doc comments and some methods have been removed. Find the full example at EXT:blog_example/Classes/BlogController.php:

Classes/BlogController.php
 <?php

 namespace FriendsOfTYPO3\BlogExample\Controller;
 use FriendsOfTYPO3\BlogExample\Domain\Model\Blog;

 class BlogController
       extends \TYPO3\CMS\Extbase\Mvc\Controller\ActionController {

     public function indexAction(): void
     {
         $this->view->assign('blogs', $this->blogRepository->findAll());
     }

     public function newAction(Blog $newBlog = null): void
     {
         $this->view->assign('newBlog', $newBlog);
         $this->view->assign('administrators', $this->administratorRepository->findAll());
     }

     public function createAction(Blog $newBlog): void
     {
         $this->blogRepository->add($newBlog);
         $this->redirect('index');
     }

     public function editAction(Blog $blog): void
     {
         $this->view->assign('blog', $blog);
         $this->view->assign('administrators', $this->administratorRepository->findAll());
     }

     public function updateAction(Blog $blog): void
     {
         $this->blogRepository->update($blog);
         $this->redirect('index');
     }

     public function deleteAction(Blog $blog): void
     {
         $this->blogRepository->remove($blog);
         $this->redirect('index');
     }

 }

The method indexAction() within the BlogController is responsible for showing a list of blogs. We also could have called it showMeTheListAction(). The only important point is, that it ends with Action in order to help Extbase to recognize it as an action. newAction() shows a form to create a new blog. The createAction() then creates a new blog with the data of the form. The pair editAction() and updateAction() have a similar functionality for the change of an existing blog. The job of the deleteAction() should be self explaining.

Tip

Those who already worked with the model view controller pattern will notice, that the controller has only a little amount of code. Extbase aims for the slim controller approach . The controller is exclusively responsible for the control of the process flow. Additional logic (especially business or domain logic) needs to be separated into classes in the subfolder Domain.

The request determines which controller action combination will be called. The dispatching and matching of actions happens in the Dispatcher and in \TYPO3\CMS\Extbase\Mvc\Controller\ActionController. The BlogController inherits all methods from it, by deriving it from this class.

<?php
declare(strict_types = 1);

namespace FriendsOfTYPO3\BlogExample\Controller;

use TYPO3\CMS\Extbase\Mvc\Controller\ActionController;

class BlogController extends ActionController
{
    // ...
}

If no specific action information is given, the default action will be called; in our case the indexAction(). The indexAction() contains only one line in our example (as shown above), which looks like this:

<?php
declare(strict_types = 1);

namespace FriendsOfTYPO3\BlogExample\Controller;

use FriendsOfTYPO3\BlogExample\Domain\Repository\BlogRepository;
use TYPO3\CMS\Extbase\Mvc\Controller\ActionController;

class BlogController extends ActionController
{
    protected $blogRepository;

    public function __construct(BlogRepository $blogRepository)
    {
        $this->blogRepository = $blogRepository;
    }

    public function indexAction()
    {
        $allAvailableBlogs = $this->blogRepository->findAll();
        $this->view->assign('blogs', $allAvailableBlogs);
    }
}

In the first line of the indexAction the repository is asked to fetch all available blogs. In the second line those blogs are assigned to the view to be displayed. So the repository is responsible for fetching the data, the view is responsible for displaying it and the controller connects and “controls” these parts.