Re: p6: Returning the freshest response

Martin Thomson <martin.thomson@gmail.com> Mon, 01 April 2013 15:56 UTC

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References: <E56A5FA7-555D-4283-95A1-FD0030D4616A@mnot.net> <CABkgnnXbDfXN1KA-AfHcW=macw44hK346z0UuYMZYx8OXBZv4g@mail.gmail.com> <51578395.6070800@treenet.co.nz>
Date: Mon, 1 Apr 2013 08:55:09 -0700
Message-ID: <CABkgnnW6KtaLizPYi8O_gBq7jHpW9QGnZ+YxwNk96R2OMee6eA@mail.gmail.com>
From: Martin Thomson <martin.thomson@gmail.com>
To: Amos Jeffries <squid3@treenet.co.nz>
Cc: HTTP Working Group <ietf-http-wg@w3.org>
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Subject: Re: p6: Returning the freshest response
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Rather than "eliminate unwanted responses", because in Mark's example,
both were acceptable with different qvalues, how about "select
preferred responses".

On 30 March 2013 17:30, Amos Jeffries <squid3@treenet.co.nz> wrote:
> On 30/03/2013 4:47 a.m., Martin Thomson wrote:
>>
>> On 28 March 2013 20:10, Mark Nottingham <mnot@mnot.net> wrote:
>>>
>>> """
>>> If multiple selected responses are available, the cache will need to
>>> choose one to use. If a selecting header has a known mechanism for doing so
>>> (e.g., qvalues on Accept and similar request headers), it MAY be used to
>>> select one; otherwise, the most recent response (as determined by the Date
>>> header field) is used, as per Section 4.
>>> """
>>
>> This seems good.  The "it" in "it MAY be used to select one" is
>> perhaps ambiguous, but I don't see how to fix it without making it
>> even harder to parse :)
>>
>
> Perhapse this is a bit better?
>
> "
>
> If multiple selected responses are available, the cache will need to choose
> one to use. When a selecting header has a known mechanism for doing so
> (e.g., qvalues on Accept and similar request headers), that mechanism SHOULD
> be used to eliminate unwanted responses; of the remainder, the most recent
> response (as determined by the Date header field) is used, as per Section 4.
>
> "
>
> Making it clear that Date mechanism still applies, but only after the
> negotiation filtering has been done. AFAIK that is how it always gets done
> in practice anyway.
>
> Amos
>
>