Re: Alt-Svc + Proxy Pac

[Ryan Hamilton <[e-mail]>]

On Fri, Apr 3, 2015 at 11:03 AM, Patrick McManus <[e-mail]>
wrote:

> I agree with martin's suggested resolution.
>
> fwiw the original netscape documentation says that the host argument is
> the host extracted from the url for convenience (what else could it say?).
> I think making existing pacs do indeterminate things based on which
> argument they are looking at is a mistake.
>
> separately - there has been some talk about standardizing modern pac - One
> thing we could do in that space is make the list of alternatives available
> to the PAC file though a separate variable, argument, or helper function.
> The PAC is really about routing afterall. It could not only select a proxy
> with that information, it could also implement alternate selection (through
> some new return mechanism) and return DIRECT.
>

​Something like that would be great. If there are several alternative
available for a given request, a browser probably won't attempt to connect
to all of them at once, instead it will likely pick one and connect to
that. This makes me think that we'd want an method like:

function FindProxyForUrl(url, alternative)


​Where |alternative|​ is the alternative service being used. For example:

FindProxyForUrl("http://internal.example.com",

                {"h2", "external.example.com", 443});

FindProxyForUrl("https://external.example.com",
                {"QUIC", "external.example.com", 443});


​Or some such...

Cheers,

Ryan
​