RE: [xri] Demoting 'priority' requirement

[Eran Hammer-Lahav <eran@hueniverse.com>]

> -----Original Message-----
> From: Will Norris [mailto:will@willnorris.com]
> Sent: Thursday, August 20, 2009 12:31 PM
> To: XRI TC
> Subject: Re: [xri] Demoting 'priority' requirement
> 
> 
> On Aug 20, 2009, at 12:01 PM, Eran Hammer-Lahav wrote:
> 
> > I would like to change the use of the 'priority' attribute from
> > 'should' to 'may' as in:
> >
> > "When these elements appear more than once within the same parent,
> > XRD publishers *MAY* use the priority attribute to prioritize
> > selection of these element instances."
> >
> > The 'priority' attribute is the one thing about XRD I hear the most
> > complaints about.
> 
> What is the actual complaint?  Concern about the extra processing?

No. The extra work by publishers when it makes no actual difference. This is about publishers, not clients.

> > While it is an important and powerful feature, I am not sure what
> > value is gained by making it a 'should'. The sentence above also
> > fails to point that multiple Links with different Rel values have no
> > use of priority if the Rel values do not repeat across links.
> > Changing it to 'may' solves that.
> 
> Then we should change the sentence to reflect that fact if need be.
> The section on resource selection seems to do a pretty good job of
> pointing out that Links are first filtered based on a selection
> criteria and *then* sorted by priority.  This is indeed an important
> feature, and the softer we word it, the more likely are to see it
> implemented inconsistently.  If the XRD publisher goes to the effort
> of explicitly specifying a priority preference, then I do think that
> consumers **should** respect that priority.

Again, I am only talking about the publisher part. The client should still respect that explicit priorities set by the publisher.
 
EHL