Re: GET on a reference

Roy T. Fielding wrote:

> >My proposal is that GET, HEAD, PUT, or POST on a reference
> >should return 302 (Moved Temporarily)
>
> That is only one of the two possible things an author might want
> to happen, the other being an internal redirect that makes it seem
> like the resource has a "copy" at that URI.

Mmm, that's possible (in the case of references on the same server), but it
doesn't sound very desirable, for two reasons.  First, if the target
resource is HTML, then relative links will be relative to the wrong URI.
Second, it would result in the resource being cached separately for each URI
that references it (the target URI and each reference).  (A 302 is not
cachable by default, but it can be marked cachable with Cache-Control:; a
DAV server could declare its referential resources cachable just like any
other document.) Caching N copies of the same document is a Bad Thing.

The only advantage I could see to an internal redirect is in cutting down on
a round trip; but, if it breaks the cache, then we have a net increase in
round trips.

> >also include some DAV-specific header, indicating that the
> >resource is a reference, so that a DAV-aware client would
> >understand that the redirection was being done through DAV
> >(as opposed to some server-specific configuration).
>
> You should elaborate as to why there needs to be any such distinction.

Mmm, because a DAV client should be able to tell the difference between
references it can manipulate and ones it can't.

> It would be nice if a reference-only resource had a property that
> distinguished it as such,

DAV:resourcetype

--
/====================================================================\
|John (Francis) Stracke    |My opinions are my own.|S/MIME supported |
|Software Retrophrenologist|=========================================|
|Netscape Comm. Corp.      | Cogito ergo Spud.  (I think, therefore  |
|francis@netscape.com      |  I yam.)                                |
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New area code for work number: 650

Received on Friday, 26 June 1998 19:02:42 UTC