Breaking: #92853 - Method canProcessRequest has been removed

See forge#92853

Description

Method TYPO3\CMS\Extbase\Mvc\Controller\ActionController->canProcessRequest() had been called to check if the currently passed in request could be handled by the controller. This allowed to handle additional request types other than the default one Extbase delivers. This would have only be useful if a user implemented a request which didn't extend the Extbase request and therefore didn't necessarily comply with its API. This however would have only been possible if the user registered a custom request handler, violating the method signature of TYPO3\CMS\Extbase\Mvc\RequestHandlerInterface->handleRequest().

Back in 2012 this was an option to use Flow and Extbase interchangeably which was never possible, and to allow Extbase Command Controllers via a CLI Request object, which was removed in TYPO3 v10.

To unify the request/response handling and making it PSR-7 compatible, this check has simply been removed along with its exception \TYPO3\CMS\Extbase\Mvc\Exception\UnsupportedRequestTypeException.

Impact

Actually very little if this feature had been used to have the controller handle custom requests that extend the Extbase request. Custom requests with a different api than the one needed by the framework will result in fatal errors.

Affected Installations

All installations with Extbase controllers that have overridden property TYPO3\CMS\Extbase\Mvc\Controller\ActionController::$supportedRequestTypes or method TYPO3\CMS\Extbase\Mvc\Controller\ActionController->canProcessRequest() and all installations which used \TYPO3\CMS\Extbase\Mvc\Exception\UnsupportedRequestTypeException in some way.

Migration

There isn't that one code migration path. If you intend to extend (XClass) the request object to add further properties/methods, you can still do so and nothing actually changes. If you violated the api, implemented custom request builders and handlers that handled requests with a different api than the one needed by the framework, you will encounter fatal errors eventually.