Re: p2: Content-Length in HEAD responses

Zhong Yu <zhong.j.yu@gmail.com> Sat, 20 April 2013 17:21 UTC

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Date: Sat, 20 Apr 2013 12:20:12 -0500
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From: Zhong Yu <zhong.j.yu@gmail.com>
To: Mark Nottingham <mnot@mnot.net>
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Subject: Re: p2: Content-Length in HEAD responses
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On Sat, Apr 20, 2013 at 3:41 AM, Mark Nottingham <mnot@mnot.net> wrote:
> p2 4.3.2 says:
>
>     Aside from the payload header fields (Section 3.3), the server SHOULD send the same header fields in response to a HEAD request as it would have sent if the request had been a GET.

Just to be clear, this sentence *allows* payload headers to be sent, correct?

On the other hand, the wording seems to imply that if a payload header
is sent, it doesn't have to be what it would be if the request had
been a GET.

Does it actually intend to say

    the server SHOULD send the same header fields in response to a
HEAD request as it would have sent if the request had been a GET,
except that the payload header fields can be omitted.

However I don't understand the "except" clause - why not require *all*
header fields to be sent as if they would be for a GET request.

Zhong Yu

>
> The payload header fields include Content-Length, which in my testing is pretty common in HEAD responses. Was this an oversight, or intentional?
>
> (We already have an exception for HEAD responses in p1's message body length algorithm, section 3.3.3).
>
>
> --
> Mark Nottingham   http://www.mnot.net/
>
>
>
>