Add PSR-7 TagHandler::tagResponse()

[ddeboer]

Currently, we only have tagResponse() in the bundle (for Symfony responses). Now PSR-7 has been accepted, however, we could also add this method to the library, setting tags on a PSR-7 response.

It’s then up for debate whether we want to override this in the bundle, or use Symfony’s PSR-7 bridge to convert between the two response types.

[dbu]

ah, indeed. this will become tricky with type hinting in the method however. best would be if we find a way that works for both PSR 7 and symfony. in a non-surprising way. maybe no typehint but instanceof checks?

[ddeboer]

Well, so far the library does not depend on Symfony requests/responses. I suggest we keep it that way and implement tagResponse() in the library (PSR-7 response) and override/decorate it in the bundle (Symfony response).

[dbu]

agreed. but we need to not have a type hint on `tagResponse` or we get into a conflict with https://github.com/FriendsOfSymfony/FOSHttpCacheBundle/blob/master/Handler/TagHandler.php#L20 (will need to change the bundle method signature too, of course). then in the bundle we check instanceof symfony Response and if so handle it, otherwise call the lib, which checks instanceof psr7 Response and handles or fails on anything else.