Re: Alt-Svc + Proxy Pac

[Francesco Chemolli <[e-mail]>]

On Fri, Apr 3, 2015 at 4:35 PM, Ryan Hamilton <[e-mail]> wrote:
> Howdy Folks,
>
> I'm curious how Alt-Svc is expect to work with Proxy PAC files. Consider the
> scenario where http://www.example.com/ has an Alt-Svc that specified http/2
> on mail.example.com:443. When the browser decides to make an http/2 (over
> TLS) connection to mail.example.com, on behalf of http://www.example.com,
> what URL and host should the browser pass to the PAC file's
> FindProxyForURL() method?
>
> I can argue both cases.
>
> * It should pass in the requested url (http://www.example.com/) because that
> is the URL being requested. There is no other URL.
> * It should pass in a pseudo url (https://mail.exmaple.com/) because, for
> example, access to mail.example.com may well requires use of a proxy to
> access. By passing in the request URL, the PAC file does not have the
> opportunity to send the connection to the correct proxy.
>
> Thoughts?

Hi Ryan,
  good point.
  I favor the second option, as in current corporate environments (the
main users of pacfiles, I expect) different destinations may require
very different forwarding paths, so it's best to have the earliest
possible decision point.
I also suggest considering a third, longer-term option: seeking an
agreement among impementors about modernizing (and possibly
standardizing) the pac-file API.

-- 
    Francesco Chemolli
    Squid Developer