Feature: #99746 - New PSR-14 SlugRedirectChangeItemCreatedEvent 

Description 

A new PSR-14 event \TYPO3\CMS\Redirects\Event\SlugRedirectChangeItemCreatedEvent has been added to TYPO3 Core. This event is fired in the \TYPO3\CMS\Redirects\RedirectUpdate\SlugRedirectChangeItemFactory and allows extension authors to manage the redirect sources for which redirects should be created.

The event features the following methods:

• getSlugRedirectChangeItem() : Returns the current \TYPO3\CMS\Redirects\RedirectUpdate\SlugRedirectChangeItem
• setSlugRedirectChangeItem() : Can be used to set a new or changed SlugRedirectChangeItem

TYPO3 already implements the \TYPO3\CMS\Redirects\EventListener\AddPlainSlugReplacementSource listener. It is used to add the plain slug value based source type, which provides the same behaviour like before. Implementing this as a Core listener gives extension authors the ability to remove the source added by AddPlainSlugReplacementSource , when their listeners are registered and executed afterwards. See the example below.

It is required for custom source class implementations to implement the \TYPO3\CMS\Redirects\RedirectUpdate\RedirectSourceInterface . Using the interface allows to detect custom source class implementations automatically. Additionally, this allows to transport custom information and data.

Registration of the event in your extension's Services.yaml:

MyVendor\MyExtension\Redirects\MyEventListener:
  tags:
    - name: event.listener
      identifier: 'my-extension/redirects/add-redirect-source'
      after: 'redirects-add-plain-slug-replacement-source'

The corresponding event listener class:

namespace MyVendor\MyExtension\Redirects;

use MyVendor\MyExtension\Redirects\CustomSource;
use TYPO3\CMS\Redirects\Event\SlugRedirectChangeItemCreatedEvent;
use TYPO3\CMS\Redirects\RedirectUpdate\PlainSlugReplacementRedirectSource;
use TYPO3\CMS\Redirects\RedirectUpdate\RedirectSourceCollection;

final class MyEventListener {
    public function __invoke(SlugRedirectChangeItemCreatedEvent $event): void
    {
        // Retrieve change item and sources
        $changeItem = $event->getSlugRedirectChangeItem();
        $sources = $changeItem->getSourcesCollection()->all();

        // remove plain slug replacement redirect source from sources
        $sources = array_filter(
            $sources,
            fn ($source) => !($source instanceof PlainSlugReplacementRedirectSource)
        );

        // add custom source implementation
        $sources[] = new CustomSource();

        // replace sources collection
        $changeItem = $changeItem->withSourcesCollection(
            new RedirectSourceCollection(...array_values($sources))
        );

        // Update changeItem in the event
        $event->setSlugRedirectChangeItem($changeItem);
    }
}

Custom source implementation (example):

namespace MyVendor\MyExtension\Redirects;

use TYPO3\CMS\Redirects\RedirectUpdate\RedirectSourceInterface;

final class CustomSource implements RedirectSourceInterface
{
    public function getHost(): string
    {
        return '*';
    }

    public function getPath(): string
    {
        return '/some-path';
    }

    public function getTargetLinkParameters(): array
    {
        return [];
    }
}

Impact 

With the new SlugRedirectChangeItemCreatedEvent , it is possible to manage the redirect sources for which redirects should be created. It furthermore allows to influence existing Core functionality.