Re: Last-Modified header in 304 and 206 responses

Mark Nottingham <mnot@mnot.net> Wed, 25 April 2012 05:18 UTC

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Date: Wed, 25 Apr 2012 15:16:56 +1000
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Subject: Re: Last-Modified header in 304 and 206 responses
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Resent-Date: Wed, 25 Apr 2012 05:17:37 +0000

Thanks for noticing. This appears to be a leftover from <http://trac.tools.ietf.org/wg/httpbis/trac/ticket/345>, which I've just reopened.

Cheers,


On 07/04/2012, at 9:28 AM, Zhong Yu wrote:

> In RFC2616, Last-Modified header was not allowed in 304 and 206(to an
> If-Range request)
> 
>  http://tools.ietf.org/html/rfc2616#section-10.3.5
>  http://tools.ietf.org/html/rfc2616#section-10.2.7
> 
> In draft 19, Last-Modified is allowed/required in 206/If-Range, but
> still forbidden in 304
> 
>  http://tools.ietf.org/html/draft-ietf-httpbis-p4-conditional-19#section-4.1
>  http://tools.ietf.org/html/draft-ietf-httpbis-p5-range-19#section-3.1
> 
> Any reason for the asymmetry?
> 
> Furthermore, why must we exclude other entity headers in 304 and
> 206/If-Range? There are only 3 of them: Content-Encoding,
> Content-Language, Content-Type. They can't have any meaningful impact
> on performance if they are included in the response. Do they really
> deserve a "SHOULD NOT be included"?
> 
> Zhong Yu
> 

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