Subject: comments spec: id URIs in @href, vs 301 Moved

From: Eric Scheid <[email-masked]>
Date: Fri, 05 Aug 2005 12:41:29 +1000

A question...

If I have a store of entries, which of course contain many <link>s, and at
some point I retrieve various of those links and find that some of them
respond with 301 Moved and a new Location ... should I then be updating the
<link>s in my store? What if those particular <links> had
@rel="in-reply-to", and per that spec would be the <id> URIs. Would updating
those URIs be wrong?

Of course if updating the store at all would be wrong then all bets are off.

e.

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From: "A. Pagaltzis" <[email-masked]>
Date: Fri, 5 Aug 2005 05:30:36 +0200

* Eric Scheid <[email-masked]> [2005-08-05 04:55]:
> What if those particular <links> had @rel="in-reply-to", and
> per that spec would be the <id> URIs. Would updating those URIs
> be wrong?

If an atom:id happened to be a dereferencable HTTP URI and
dereferencing produced 301, what would you do?

The same answer (ie, nothing at all) applies to “in-reply-to.”
Those aren’t links to a web resource. They’re IDs, and as such
eternal.

Regards,
-- 
Aristotle Pagaltzis // <http://plasmasturm.org/>

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From: Eric Scheid <[email-masked]>
Date: Fri, 05 Aug 2005 13:50:14 +1000

On 5/8/05 1:30 PM, "A. Pagaltzis" <[email-masked]> wrote:

> The same answer (ie, nothing at all) applies to ³in-reply-to.²
> Those aren¹t links to a web resource. They¹re IDs, and as such
> eternal.

ah, but how do you know those URIs are id's?

or more specifically, is the following URI an id or a location?

    <link rel="something-you-don't-know" href="..." />

e.

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From: "A. Pagaltzis" <[email-masked]>
Date: Fri, 5 Aug 2005 06:06:44 +0200

>     <link rel="something-you-don't-know" href="..." />

You don’t know. Just goes to show once again that Antone was
right all along to rail against abusing atom:link for that
purpose.

Of course you could say that consumers should disregard links
with relationships they don’t understand – which, incidentally,
is equivalent to disambiguating whether atom:link/@href is just
any URI or supposed to be dereferencable. Other than those of us
discussing the threading extension, noone has opined about that
matter.

Regards,

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From: James M Snell <[email-masked]>
Date: Thu, 04 Aug 2005 21:38:37 -0700

>    <link rel="something-you-don't-know" href="..." />
It's entirely dependent on the type of link. If a link relation is used 
that you're not familiar with, you cannot make any assumptions about 
whether or not the href is dereferenceable or not.  You must treat is as 
an opaque identifier.

- James

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From: James M Snell <[email-masked]>
Date: Thu, 04 Aug 2005 21:41:43 -0700

>discussing the threading extension, noone has opined about that
I'm all for taking the approach of having consumers disregard link 
relations they're not familiar with only I would word it differently.  
If a consumer comes across a link relation it is not familiar with, the 
consumer should treat the href URI as an opaque identifier and not 
assume that it is dereferenceable.  Otherwise, the definition of the 
link relation should unambiguously indicate whether or not the href URI 
is or is not dereferenceable.

- James