Subject: Re: 300 Multiple Choices and safe methods

From: Henrik Nordström <[email-masked]>
Date: Sun, 09 May 2010 21:35:45 +0200

ons 2010-03-10 klockan 19:58 -0800 skrev Robert Brewer:
> I noticed while working on an automated client today that,
> while 301, 302, 303, and 307 have a lot to say about whether
> a UA may automatically redirect a request other than GET or
> HEAD, the 300 response doesn't make any mention of methods:
> 
>    If the server has a preferred choice of representation, it SHOULD
>    include the specific URI for that representation in the Location
>    field; user agents MAY use the Location field value for automatic
>    redirection.  This response is cacheable unless indicated
> otherwise.
> 
> Should it?

I would assume the intention is that 300 inicates where the different
resources matching the requested URI can be found and that the intention
is that the same method should be retried on the selected choice, just
as it is for most of the other 3xx redirection responses.

Actually if you read the 301 and 302 specifications they do not
explicitly say how other methods than GET/HEAD should be handled except
for the note that many user agents are broken and automatically switches
to GET.

303 & 307 do explicitly mention how they are supposed to be handler, but
this is quite natural as these were added to address the issue that many
implementations is not conforming to the 301 & 302 specifications,
enabling the world to move forward to a well known state without
breaking existing applications more than they already are.

Regards
Henrik