RE: Frag Ids in location headers

Hello Thomas,

> Stuart,
> 
> On Mon, Nov 27, 2006 at 05:43:19PM -0000, Williams, Stuart 
> (HP Labs, Bristol) wrote:
> > I'd had a look at the "Best Practice Recipes for Publishing RDF 
> > Vocabularies" [1] and was troubled by one small thing in receipe #4.

> > In the third diagram [2] does a redirect with a Location header that

> > includes a fragment in the redirection.
> > 
> > It's not at all clear to me that the http specs allows the inclusion

> > of a fragment id in a redirection. I know that the redirections on 
> > http://purl.org/dc/elements/1.1/title etc. do something similar 
> > (curiously, the last time I looked there was no 'target' in the 
> > resulting representation corresponding the location URI 
> > http://dublincore.org/2006/08/28/dces.rdf#title).
> 
> On this last point...:
> 
> As written, the recipes in section 4 call for the use of HTML 
> anchors in the HTML document about the vocabulary, but not 
> for the use of corresponding targets in the RDF serializations [1].

Ok... yes I missed that the rewrite rules and the diagrams were only
adding fragIds in the HTML redirection cases. I can also see the utility
of this approach in terms of 'positioning' a browser at the relevant
text in a larger document. I guess it works (haven't tried myself) and
that the browser would throw away all but the last frag id if there were
multiple redirections with frag ids.

On the question of frag id in Location headers there is an errata to the
http spec at: http://skrb.org/ietf/http_errata.html#location-fragments
which indicates that they are allowed - so that basically resolves this
thead. The errata leaves open the correct way to handle multiple fragId
in a sequence of redirections, however it notes that current behaviour
is to retain the most recent frag id (in the redirection chain).

> Tom
> 
> [1] 
> http://www.w3.org/TR/2006/WD-swbp-vocab-pub-20060314/#recipe4example

Thanks

Stuart
--

Received on Tuesday, 28 November 2006 15:56:50 UTC