[whatwg] Gears caching at identical URIs (was: Gears design goals)

[Robert Sayre]

On 6/26/07, Aaron Boodman <boogs at youngpup.net> wrote:
> ---------- Forwarded message ----------
> From: Robert O'Callahan <robert at ocallahan.org>
> > - One major issue that we found here was that lots of existing
> > applications serve different resources at the same URI depending on
> > who is logged in. We could ask these applications to redesign so that
> > they don't do that, but we would prefer to not have to.
> >
> Understood, but this seems to add substantial complexity to the model.
> Is it really a big deal to restrict users to one login available
> offline? A browser can of course support multiple profiles or
> something similar to address that use case without complicating the
> development model.

To me, it looks like the caching mechanisms in HTTP 1.1 can satisfy
this requirement. I think Rob is correct that it adds substantial
complexity, but it is already required. I've been viewing offline
resources as things that are too expensive to revalidate. On the
server, this is the stuff you would generate with a cron job instead
of checking whether you needed to regenerate the output.

Basically, I think offline caches should respect the Vary: HTTP
header, and maybe more. Applications will need to do this right
anyway, if they want to function correctly in the presence of ISP HTTP
proxies (AOL, TMobile, etc),  corporate firewalls, and server-side
stuff like Citrix Netscalers.

-- 

Robert Sayre

"I would have written a shorter letter, but I did not have the time."