Re: Review of new HTTPbis text for 303 See Other

On Thu, Jul 9, 2009 at 7:16 PM, Roy T. Fielding<fielding@gbiv.com> wrote:
> On Jul 9, 2009, at 6:17 AM, J Ross Nicoll wrote:
>
>> Roy T. Fielding wrote:
>>
>>>> That just seems plain false. A 303 does not indicate that something
>>>> does not exist. It simply indicates that the server, for reasons which
>>>> may be entirely opaque and nobody is under any obligation to explain,
>>>> has decided to redirect the query elsewhere.
>>>
>>> No, we have other redirect codes for that.
>>
>> As I understand it, 301 (moved permanently), 302 (found) and 307 (not
>> modified) all indicate a different location for the resource, never for
>> an alternative to it. 304 is "Not modified", and 305/6 are
>> deprecated/reserved respectively. So, I don't think there is any other
>> redirect code for "Instead of the resource you requested, please see
>> this resource instead"...
>
> The only reason for a server to say "see this other resource
> instead" to a GET request is that the person who configured
> the server knows that this other resource is not the same as
> the requested resource (i.e., not a 301/302/307) and yet wants
> the client directed to that resource because it is more responsive
> to the client's request than responding with a 404 or 410.

> The only way a server can be responsive to the client's original
> GET request (i.e., not broken or lying) is if the 303 response
> points to a resource that describes the originally requested
> resource.  Any other result would be pointlessly random, which
> would be silly because 302 is already provided for pointlessly
> random redirects.

"describes", "is about", "has topic" - there are a number of names for
the relation of the 303 response to the originally requested resource.
I agree with your assessment here and would welcome stronger language
in the specifications that make clear this expectation about 303
responses.

-Alan
>
> ....Roy
>
>

Received on Saturday, 11 July 2009 23:29:21 UTC