Re: Cache control in trailers?

On Wed, Feb 03, 2021 at 09:44:10AM +0000, Poul-Henning Kamp wrote:
> --------
> Martin Thomson writes:
> > On Wed, Feb 3, 2021, at 19:22, Poul-Henning Kamp wrote:
> > > If we want enable that, we should move *all* headers and status to the 
> > > trailer, so that no confusion is possible.
> >
> > Oddly, I agree, though this comes with a whole lot of problems with message processing at intermediaries and whatnot.
> 
> I'm not sure I see any _major_ problems.
> 
> If the client has indicated it can do 142, a non-policy intermediary can just
> pass stuff along, and that realizes the full production/transmission overlap.

Please, look at what I proposed before, consisting in letting the origin
server mark the response as non-cacheable first, and announcing that this
might change in the trailers. Non-compatible intermediaries will simply not
cache, compatible ones will be able to decide at the end. We could imagine
supporting more options like short duration by default, long duration once
complete, etc. No need for abusing every corner case and making sure to break
every single intermediary in the middle.

Willy

Received on Wednesday, 3 February 2021 10:17:24 UTC