Re: dont-revalidate Cache-Control header

Mark Nottingham <mnot@mnot.net> Sat, 11 July 2015 01:37 UTC

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From: Mark Nottingham <mnot@mnot.net>
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Date: Sat, 11 Jul 2015 11:33:30 +1000
Cc: Amos Jeffries <squid3@treenet.co.nz>, ietf-http-wg@w3.org
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To: Ben Maurer <ben.maurer@gmail.com>
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Subject: Re: dont-revalidate Cache-Control header
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Hi Ben,

> On 11 Jul 2015, at 3:14 am, Ben Maurer <ben.maurer@gmail.com> wrote:
> 
> 2) Create a new behavior that websites can opt in to. Ensure that UAs implement it consistently. This has less risk of breaking existing sites, though I understand the hesitance to have a header that says "no *REALLY* trust my expiration times". Perhaps the header is poorly advertising the functionality that we wish to achieve. A better name/behavior might be Cache-control: content-addressed. content-addressed would signal that the contents of the current URL is a pure function of the URL itself. IE, that the contents will never change. It would take priority over a max-age header and signal to the browser that the resource should be permanently cached. 

This seems like the crux of the matter. A CC extension is one way to do this, but I wonder if a more appropriate place might be in HTML, since this is really about how the browser behaves in reaction to user input, not how the cache behaves.

Cheers,


--
Mark Nottingham   https://www.mnot.net/