PSR-14 events

Target group: Developers

Table of Contents

Introduction

You can enhance the functionality in the schema extension with PSR-14 event listeners. An event listener receives an event that provides methods for retrieving and setting dedicated properties.

Render additional types

The event allows to add markup in cases where no controller is available, for example, if you want to enrich a page with structured data depending on the doktype of a page.

The event \Brotkrueml\Schema\Event\RenderAdditionalTypesEvent provides the following methods:

getRequest(): \Psr\Http\Message\ServerRequestInterface: Returns the PSR-7 request object.

addType(TypeInterface ...$type): void: Add one or more type models.

addMainEntityOfWebPage(TypeInterface $mainEntity): void: Add a main entity.

Example

In the following example we add structured data markup depending on the doktype of the page:

EXT:my_extension/Classes/EventListener/AddMarkupToArticlePages.php

<?php

declare(strict_types=1);

namespace MyVendor\MyExtension\EventListener;

use Brotkrueml\Schema\Event\RenderAdditionalTypesEvent;
use Brotkrueml\Schema\Type\TypeFactory;
use TYPO3\CMS\Core\Attribute\AsEventListener;
use TYPO3\CMS\Frontend\Page\PageInformation;

#[AsEventListener(
    identifier: 'my-extension/add-markup-to-article-pages',
)]
final readonly class AddMarkupToArticlePages
{
    public function __construct(
        private TypeFactory $typeFactory,
    ) {}

    public function __invoke(RenderAdditionalTypesEvent $event): void
    {
        // The "frontend.page.information" attribute is available since TYPO3 v13.
        // Use the "frontend.controller" attribute (TSFE) in older TYPO3 versions
        // to retrieve the page record.
        /** @var PageInformation $pageInformation */
        $pageInformation = $event->getRequest()->getAttribute('frontend.page.information');
        $page = $pageInformation->getPageRecord();
        if ($page['doktype'] !== 12345) {
            return;
        }

        // Only for doktype 12345
        $article = $this->typeFactory->create('Article');
        $article->setProperty('name', $page['title']);
        // ... and set some other properties

        $event->addType($article);
    }
}

The method __invoke() implements the logic for rendering additional types. It receives the RenderAdditionalTypesEvent. You can add as many types as you like.