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Re: please add Accept header to http request containing application/xhtml+xml

From: Etienne Miret <elimerl@gmail.com>
Date: Mon, 21 Apr 2008 20:47:30 +0200
Message-ID: <480CE142.8030502@gmail.com>
To: Alexandre Alapetite <alexandre@alapetite.net>
CC: Dean Edridge <dean@55.co.nz>, www-validator@w3.org

Hi Alexandre,

Alexandre Alapetite wrote:
> Internet Explorer (4, 5, 6, 7, 8) does send an Accept header, and it
> is not empty.
No, but according to the standard, the headers they send mean *exactly* 
the same thing as if they were not sending any Accept header. That is, 
they mean that IE accept any media-type, with none preferred over the 

> Dean Edridge wrote:
>> IMHO it is not good practise for any web server to send XHTML
>> to a user-agent without first knowing that the user-agent accepts XHTML.
>> This may seem like an odd concept to some but it is just the way things are
>> if you want to use XHTML on the web today.
> I am not aware of any user agent that does NOT send an Accept header
> at all, and to which it would be problematic to send
> application/xhtml+xml.
This is a rather special case. Instead of having a special case for IE, 
you have a special case for the few UA who send no Accept header at all, 
although it is suppose to mean the same thing as "Accept: */*".

> The following algorithm does not require any user agent sniffing, is
> not that dirty, and works with all user agents I have been able to put
> my hands on (including W3C validator):
Well, if I'm correct, Nikita The Spider sends an Accept header of "*/*", 
and with this algorithm, you would send it HTML although it is very able 
to handle XHTML.

> In PHP, it is possible to implement a full standard
> content negotiation mechanism, but it is not possible using a simple
> rewrite rule in a .htaccess.
If you do full standard content negotiation, you'll get random support 
for IE. Really random support, that's what I have on my website. Since 
IE pretends it likes XHTML as much as HTML, my server will sometime send 
HTML, and sometime send XHTML.


Etienne Miret
Ne m'envoyez pas de fichier Word SVP, je ne peux pas les lire !
Don't send me Word attachments please, I can't read them!
Received on Monday, 21 April 2008 18:48:12 UTC

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