Feature: #96147 - New PSR-14 RedirectWasHitEvent

See Issue #96147

Description

A new PSR-14 event \TYPO3\CMS\Redirects\Event\RedirectWasHitEvent has been added to TYPO3 Core. This event is fired in the \TYPO3\CMS\Redirects\Http\Middleware\RedirectHandler middleware and allows extensions to further process the matched redirect and to adjust the PSR-7 response.

The event features the following methods:

  • getRequest(): Returns the current PSR-7 Request
  • getResponse(): Returns the current PSR-7 Response
  • setResponse(): Can be used to set / update the PSR-7 Response
  • getMatchedRedirect(): Returns the matched redirect record
  • setMatchedRedirect(): Can be used to set / update the matched redirect record
  • getTargetUrl(): Returns the resolved redirect target

TYPO3 already implements the IncrementHitCount listener. It is used to increment the hit count of the matched redirect record, if the feature is enabled. In case you want to prevent the increment in some cases, e.g. when the request was initiated by a monitoring tool, you can either implement your own listener with the same identifier (redirects-increment-hit-count) or add your custom listener before and dynamically set the records disable_hitcount flag.

Registration of the Event in your extensions’ Services.yaml:

MyVendor\MyPackage\Redirects\MyEventListener:
  tags:
    - name: event.listener
      identifier: 'my-package/redirects/validate-hit-count'
      before: 'redirects-increment-hit-count'

The corresponding event listener class:

use TYPO3\CMS\Redirects\Event\RedirectWasHitEvent;

class MyEventListener {

    public function __invoke(RedirectWasHitEvent $event): void
    {
        $matchedRedirect = $event->getMatchedRedirect();

        // This will disable the hit count increment in case the target
        // is the page 123 and the request is from the monitoring tool.
        if (str_contains($matchedRedirect['target'], 'uid=123')
            && $event->getRequest()->getAttribute('normalizedParams')->getHttpUserAgent() === 'my monitoring tool'
        ) {
            $matchedRedirect['disable_hitcount'] = true;
            $event->setMatchedRedirect(
                $matchedRedirect
            );

            // Also add a custom response header
            $event->setResponse(
                $event->getResponse()->withAddedHeader('X-Custom-Header', 'Hit count increment skipped')
            );
        }
    }
}

Impact

This event can be used to further process the matched redirect and to adjust the PSR-7 Response. It furthermore allows to influence core functionality, e.g. the hit count increment.