Subject: http://www.intertwingly.net/wiki/pie/PaceAllowDuplicateIDs

From: "Bob Wyman" <[email-masked]>
Date: Wed, 4 May 2005 21:20:43 -0400

+1 with a comment:

If this Pace is accepted (and I hope it will be) the issue of Duplicate IDs
should probably be dealt with in Mark's Implementation Guide.[1] 

Atom supports the publishing of "newer versions" of an entry which use the
same atom:id as earlier versions of the same entry. It is not required that
atom:updated be modified when a newer version is written. 

If the PaceAllowDuplicateIDs is accepted, it will be permitted to have
multiple entries with the same atom:id in a single feed. However, the Pace
language says processors "SHOULD" regard as feed generation errors any
entries which duplicate both the atom:id and atom:updated of another entry
in the same feed. Thus, feed authors who wish to publish feeds with
duplicate atom:ids should ensure that any entry which duplicates an entry
already in the feed has a different value for atom:updated. This constraint
is not a requirement of the language, but it is a clear derivative of it.

Basically, you don't have to update atom:updated unless you think it makes
sense OR you are publishing to a feed that already has an entry with the
same atom:id as the atom:id of the entry you are currently publishing.

      bob wyman

[1] http://diveintomark.org/rfc/draft-ietf-atompub-impl-guide-00.html

---

From: Tim Bray <[email-masked]>
Date: Wed, 04 May 2005 19:44:32 -0700

On May 4, 2005, at 6:20 PM, Bob Wyman wrote:

> +1 with a comment:
>  
> If this Pace is accepted (and I hope it will be) the issue of 
> Duplicate IDs should probably be dealt with in Mark’s Implementation 
> Guide.[1]

Er, I had planned to refine this a bit and then announce it to the 
group with some explanations and some other background research I did; 
so how about I promise to do that later this evening; and please 
consider waiting for that before you all pile in, pro or contra. -Tim

---

From: Graham <[email-masked]>
Date: Thu, 5 May 2005 09:56:11 +0100

On 5 May 2005, at 2:20 am, Bob Wyman wrote:

> Basically, you don’t have to update atom:updated unless you think  
> it makes sense OR you are publishing to a feed that already has an  
> entry with the same atom:id as the atom:id of the entry you are  
> currently publishing.
Or someone downstream is publishing one, of course. Which means you  
must always change atom:updated, just in case. No harm done, Tim.  
None at all.

Graham