Re: p6: Returning the freshest response

Amos Jeffries <squid3@treenet.co.nz> Sun, 31 March 2013 00:32 UTC

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Date: Sun, 31 Mar 2013 13:30:13 +1300
From: Amos Jeffries <squid3@treenet.co.nz>
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Subject: Re: p6: Returning the freshest response
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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