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Re: [XRI] Back to XRI

From: John Bradley <john.bradley@wingaa.com>
Date: Thu, 11 Sep 2008 12:54:11 -0700
Cc: "elharo@metalab.unc.edu" <elharo@metalab.unc.edu>, "www-tag@w3.org" <www-tag@w3.org>
Message-Id: <9C79F449-30FC-4472-AB99-B47E09A8EB61@wingaa.com>
To: "Booth, David (HP Software - Boston)" <dbooth@hp.com>
Thanks David,

Certainly we want any http: subscheme to be completely backwards  
compatible with existing agents.

In the case of a XRI like =jbradley where the XRI is a "identifier for  
an abstract object",  me in this case.
(Though thinking of myself as abstract still strikes me as a bit odd.)

The question of what is returned when cast as a http: URI becomes  
interesting.

In conversation with TAG members using Link headers to point at the  
URI for the XRDS meta-data seems reasonable.
We currently use a 302 redirect to point at some appropriate html  
representation for compatibility reasons.  In my case a contact page.

Stuart Williams has pointed out that using a 303 redirect would make  
it clear that the resource http://xri.net/=jbradley itself is "an  
identifier for an abstract object" and not a resource that has  
temporarily moved.

The XRI TC originally selected the 302 redirect for compatibility with  
pre http 1.1 browsers.
Changing to 303 redirects may brake some clients but it unlikely to be  
a significant issue.

I understand that some people will feel that using redirects is  
inefficient,  however it seems the only way to communicate the desired  
qualities of the identifier in http:

This still allows XRI aware applications from directly requesting the  
XRDS meta-data if they recognize the subscheme.

I will also mention that some people seem to prefer the term "http:  
profile" as a way to describe the qualities of a sub scheme.

Regards
John Bradley


On 11-Sep-08, at 12:10 PM, Booth, David (HP Software - Boston) wrote:

>
>>> On 9-Sep-08, at 8:21 AM, Elliotte Harold wrote:
>>      John Bradley wrote:
>>      [ . . . ]
>>              Do you have any feelings on integrating XRI
>> into http via the HXRI mechanism we have been discussing
>> elsewhere on this list?
>>
>>>    Not really, but I would object to anything that
>>> requires different resolution strategies for HTTP. If you
>>> give me an HTTP URL, I want to go get a representation (bit
>>> stream) without any further inspection of the path or query
>>> string or fragment ID. As long as I can do that, you're free
>>> to put anything in the URL or at the other end that you feel like.
>
> Just to be clear, a key point behind the Booth-Bradley approach[1]  
> of using an http: subscheme for XRI identifiers is that they would  
> not *require* agents to use any different resolution strategy.   
> Agents that are XRI aware could recognize the special prefix and use  
> a different resolution strategy, but other agents knowing and caring  
> little about XRIs could still use good old HTTP.
>
> 1. http://lists.w3.org/Archives/Public/www-tag/2008Jul/0093.html
>
>
> David Booth, Ph.D.
> HP Software
> +1 617 629 8881 office  |  dbooth@hp.com
> http://www.hp.com/go/software
>
> Statements made herein represent the views of the author and do not  
> necessarily represent the official views of HP unless explicitly so  
> stated.




Received on Thursday, 11 September 2008 19:54:51 GMT

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