Re: p2: Content-Length in HEAD responses

Mark Nottingham <mnot@mnot.net> Sat, 20 April 2013 10:02 UTC

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From: Mark Nottingham <mnot@mnot.net>
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Date: Sat, 20 Apr 2013 20:01:04 +1000
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To: Willy Tarreau <w@1wt.eu>
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Subject: Re: p2: Content-Length in HEAD responses
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On 20/04/2013, at 7:22 PM, Willy Tarreau <w@1wt.eu> wrote:

> On Sat, Apr 20, 2013 at 07:11:57PM +1000, Mark Nottingham wrote:
>> 
>> On 20/04/2013, at 7:06 PM, Willy Tarreau <w@1wt.eu> wrote:
>> 
>>> On Sat, Apr 20, 2013 at 06:41:01PM +1000, Mark Nottingham 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.
>>>> 
>>>> The payload header fields include Content-Length, which in my testing is
>>>> pretty common in HEAD responses. Was this an oversight, or intentional?
>>> 
>>> In my opinion it was intentional, as it's the only way for a client
>>> to know the payload size in advance without retrieving the file.
>> 
>> I was asking if it was intentional that, as currently specified, we say that
>> C-L should be *omitted* from HEAD responses.
> 
> This is not what I'm seeing in p1/3.3.2 :
> 
>   A server MAY send a Content-Length header field in a response to a
>   HEAD request (Section 4.3.2 of [Part2]); a server MUST NOT send
>   Content-Length in such a response unless its field-value equals the
>   decimal number of octets that would have been sent in the payload
>   body of a response if the same request had used the GET method.
> 
> Maybe I'm missing something or there are inconsistencies with other parts ?


I think it's an inconsistency between that and <https://svn.tools.ietf.org/svn/wg/httpbis/draft-ietf-httpbis/latest/p2-semantics.html#HEAD>.

Let's call this editorial and have the editors flip it back to design if they disagree.


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