Re: AW: AW: XHTML 2.0 and hreflang

> [Original Message]
> From: Christian Wolfgang Hujer <Christian.Hujer@itcqis.com>
> To: <ernestcline@mindspring.com>; W3C HTML List <www-html@w3.org>
> Date: 11/17/2003 6:33:37 AM
> Subject: Re: AW: AW: XHTML 2.0 and hreflang
>
>
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> Hi Ernest, dear list members,
>
>
> Am Freitag, 14. November 2003 16:09 schrieb Ernest Cline:
> > Note: You seem to be using "user" for two distinct things.
> > (1) The consumer of a document
> > (2) The creator of a document
> > I use "user" only for (1) and "author" for (2) to avoid confusion.
> >
> > If, as you seem to be indicating, that it is important that an author
> > should be able to specify a language specific version of a document,
> > that would seem to call for using a URL that refers to just that
version.
> >
> > If for example, there existed on a server:
> >  doc.en.xhtml, doc.de.xhtml, and doc.pl.xhtml
> > Then it  should be possible to have doc.pl.xhtml always refer
> > the Polish version and doc.xhtml return anyone of the three
> > according to the user agent settings as set by the user, and
> > perhaps influenced by a context menu that offered a choice
> > of any of the three to the user.
> Obviously you never had a 406 response yet.
> As soon as the negotiation is only using the language dimension,
requesting 
> doc.de.xhtml with an Accept-Language: en header is okay. But as soon as 
> content negotiation gets another dimension and is used for more than just
the 
> language such negotiating requests will result in 406 responses.
Requesting 
> doc.de for choosing between doc.de.xhtml as application/xhtml+xml and 
> doc.de.html as text/html with Accept: application/xhtml+xml and 
> Accept-Language: en gives a 406 response.
>
> That's why I want @hreflang to override or extend the user agent's
default 
> Accept-Language header.

Well of course.  Given what you've described, here is what should happen
in such a case.

1) The UA sends the request with:
   Accept: application/xhtml+xml
   Accept-Language: en
2) The server sends back the 406 response which ideally should contain
    (if I'm interpreting RFC 2616 correctly, which I may not):
   Accept: application/xhtml+xml, text/html
   Accept-Language: de
3) The user agent decides whether to request a German language
   version of the resource.  Perhaps the user agent informs the user
   and gets his input  Perhaps the user agent has a backup set of
   accept headers it uses when its initial 

(Alternatively, the UA first sends an OPTIONS request to determine
what the document supports, and then decides what to request.  This
has the downside of causing more traffic for the usual case, but has
the advantage of not sending what could be a very user specific set
of Accept headers out with every request.

In any case, having an author to be able to override the user's chosen
preference to not download the German language version strikes me
as a bad idea.  The user could have chosen a Accept-Language
field of "en,de;q=0.001" or "en,*;q=0.001" to indicate that if an
English language version of the document is not available, it should
accept a German version.  One can argue that existing user agents
do not do a good job of implement Accept headers and explaining
their consequences, but I am convinced that giving the author
the ability to override user settings is not desirable.

> By the way, most servers (including Apache HTTP 1.3.x, I didn't test this
> on 2.x yet) will not allow configuring requesting a URL doc.*.xhtml using
> a URI ending on doc.xhtml.

The specific format of the internal filename is irrelevant. So long as
it has some method of deciding that the particular version of a resource
has some particular set of characteristics.

Received on Monday, 17 November 2003 11:49:04 UTC