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Re: naive question: why prefer absolute URIs to # URIs for linked data?

From: Ian Davis <me@iandavis.com>
Date: Wed, 31 Aug 2011 21:52:17 +0100
Message-ID: <CA+Zbc2pHfTkVTMb6nvMJcdjQ6DD48N4o-+dh18FPFZG1F7+xtA@mail.gmail.com>
To: Jonathan Rees <jar@creativecommons.org>
Cc: Harry Halpin <hhalpin@ibiblio.org>, Manu Sporny <msporny@digitalbazaar.com>, www-tag@w3.org
I think there are a number of contributing factors:

1) architecturally the meaning of the fragment is determined by the media
type of the representation. Thus meaning of a hash URI depends on how you
access it.

2) Fragments are not sent to the server when they are dereferenced which
means the server has to guess what information to send. If you're storing
data for that URI in a database you have to key it against the hashless
version of the URI along with all other URIs that share that hashless part.
Also the server can't log accesses to the full URI which means you don't get
accurate analytics.

3) You can't use HTTP headers or status codes to refer to a hash URI. For
example you can't 404 a hash URI or redirect it.

4) The role of the fragment is changing in modern web development practice.
Its becoming a bearer of state and/or part of the interaction architecture
of an application. See #! URLs or javascript techniques for tabbed pages.

Ian
On 28 Aug 2011 18:27, "Jonathan Rees" <jar@creativecommons.org> wrote:
> Question to the broader www-tag readership (and beyond):
>
> I don't want to start another argument, I just want to understand the
> position that it is necessary to use absolute (i.e. hashless) URIs
> instead of hash URIs for semantic web / linked data purposes, and
> record the reasons for this position somewhere. I attempted this in
> http://www.w3.org/2001/tag/awwsw/issue57/20110625/#hash but I feel
> the case I made against # URIs there is not convincing.
>
> That is, suppose you want a URI to use in RDF as a reference (name,
> "identifier", whatever) for something other than the web page
> (document, "information resource", whatever) at that URI. Why is it so
> important that the URI be absolute, instead of one containing # ? So
> important that the defense of this right would precipitate storms of
> email messages, many containing quite strong language?
>
> This question is at the root of the httpRange-14 / ISSUE-57 dispute,
> since if # URIs worked for everyone there would be no pressure to use
> absolute URIs, and therefore no fight about whether you can use 200 or
> are required to use 303. So I'd like to understand this better than I
> do.
>
> Please be as specific and concrete as possible. I promise to do my
> best to listen patiently, treat all reasons as legitimate, and report
> impartially.
>
> Thanks for your help,
>
> Jonathan
Received on Wednesday, 31 August 2011 20:52:45 GMT

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