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

From: Tim Berners-Lee <timbl@w3.org>
Date: Fri, 2 Sep 2011 15:41:36 -0400
Cc: Jonathan Rees <jar@creativecommons.org>, Harry Halpin <
hhalpin@ibiblio.org>, Manu Sporny <msporny@digitalbazaar.com>,
www-tag@w3.org
Message-Id: <97CDCA3F-5482-4504-A67C-C4D80B692313@w3.org>
To: Ian Davis <me@iandavis.com>

On 2011-08 -31, at 16:52, Ian Davis wrote:

[snip]

> Also the server can't log accesses to the full URI which means you don't
get accurate analytics.
>

With the #it method above it can as there is a 1-1 correspondence.


The lack of the hash doesn't allow you to distinguish between those
requesting the full NIR URI with the hash and those requesting the document
URI. This may result in the same resource being served but as both are valid
URIs and may appear in different datasets for different purposes it does
limit the analytics that are possible.


> 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.

With the #it method above it can as there is a 1-1 correspondence.


There is a case where you can't and that is where URIs have been incorrectly
formed. A request to http://example.com/#it and a request
http://example.com/#not_it will appear the same and result in a response of
200 and a document describing #it in both cases, where the ideal is to be
able to return a 404 for #not_it as the resource is not found,

> 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.

The fact that people are building on the fragid in one way doesn't mean we
shouldn't
also build on it in this way.

It makes it harder to work with Linked Data in combination with a stateful
javascript site if the # is used both for stateful functionality with the
script and to indicate a NIR URI. You cannot use URIs that do both as only
one frag is allowed.


>
> Ian
>


Tim


-- 
rob

Rob Styles
Senior Technical Consultant
http://consulting.talis.com/rob-styles