我需要哪个MVC？

In general there are ActionController, Repositories, Models und Views in TYPO3 Flows domain driven MVC system. In our project we use a general File model that contains the Ressource.

Now we need a special "expert" php script like an action controller that doesn't listen to certain url actions. It should get such a File object, do something internal like logging stuff or manipulate the object after a special procedure and give back an information / return falue.

What mvc thing I need for that? An interface? A manager? How you call that and how do I initialise it in TYPO3 Flow? Or is the FileController (action controller) exact the thing I have to use for that?

This "expert" shouldn't listen to url actions but should be used like an action controller like

$expertyThing = new ../../Expertything();
$expertyThing->doCoolStuff($file);

and should can use thinks like the PersistenceManager (by injection or anyhow).

Thanks for any input for that.

I would say Service but I'm not sure if I understood you correctly.

I guess you have some FileController and you have createFileAction there, which creates new File model from uploaded resource, do some validation, transformations, renaming and save it using injected FileRepository.. And you want something in middle.

So I create FileService for that My/FileManager/Domain/Service/FileService.php - inject repository and other services there. And in action or command controllers I inject those services and they do "expert" stuff (and I don't have to duplicate code), like that:

// FileController
public function createFileAction(Resource $resource) {
    try {
        $file = $this->fileService->processAndSaveFile($resource);
    } catch (\Exception $e) {
        $this->addFlashMessage($e->getMessage(), '', Message::SEVERITY_ERROR);
        $this->forwardToReferringRequest();
    }
    $this->addFlashMessage('File created');
    $this->redirect('fileList');
}

So for me FileService do expert stuff for File - it creates new File model (maybe using FileFactory), do transformations using other services like ImageService, has repository and logger injected (but you can use Aspects for cases like logging).. and if something goes wrong it throws some FileException.

And of course FileService may implement some FileServiceInterface, and you can inject this interface to your controller and define in Objects.yaml which service should be used (it makes it more flexible, so someone else could implement it and replace your FileService not touching it).

This "Service" approach may be a little bit outdated, so maybe someone will suggest better solution.. If you want follow Flow rules, just check how they handle stuff like that in official packages.