Subject: Re: [Uri-review] Request for review of "ab:" URI scheme

From: Graham Klyne <[email-masked]>
Date: Sun, 01 May 2011 11:19:48 +0100

Barry,

My apologies, I've been a bit unwell of late and haven't got round to going over
your materials in detail.

This is mainly a "holding" message until I can properly look over that material, 
and to let you know I'm not ignoring your request.

On reflection, my general sense at this time is that an addrbook: URI scheme
might be an interesting and useful development, but I'm not yet seeing that the
requirements of Sieve alone justify introducing a new URI scheme.

I recognize this probably isn't what you want to hear.

I also recognize that you have a need in Sieve for a URI that can be used to 
denote a common notion of lists of addresses defined locally in some unspecified 
fashion.

Under the circumstances, I would agree that my earlier suggestion of using http: 
is problematic and confusing, as one might expect dereferencing of the URI to 
yield a list of addresses (or a list of entries containing addresses), which 
would not be satisfiable using the pre-existing http: dereference semantics.

Some alternative suggestions I have that might meet the immediate requirements 
of Sieve include:
- Use the existing URN namespace for IETF parameters (e.g. 
urn:ietf:param:sieve:addrbook:default).  I mentioned this previously, and 
recognize the concern mentioned by Alexey that this could be awkward for 
hand-written Sieve code, but feel that it is otherwise a technically reasonable 
approach.
- Register a new URN namespace for addrbook (or even just ab) - this could yield 
URIs like: urn:addrbook:default (or urn:ab:default)
- I think the about: scheme has extension points that might be used, yielding 
something like about:addrbook:default.  (I haven't researched this properly, so 
there could be problems here.)

These suggestions do not preclude the possibility of subsequent work to 
introduce an addrbook: scheme that serves the wider needs we've discussed.  But 
if there really does exist a desire to address those wider goals, I feel they'd 
be better addressed without being constrained by the timetable for your Sieve 
work.  While I see potential value for an addrbook: scheme, I would say the jury 
is still out regarding whether that value would justify the development of a new 
URI scheme.

#g
--

Barry Leiba wrote:
>> So, reinvention aside, I think what Barry sketches above is prima facie a
>> reasonable approach.  If there's any real advantage to an addrbook: scheme,
>> I think it is in part that it can abstract away from a particular protocol
>> or mechanism and leave just the essential capabilities exposed.
> 
> Graham, where are we on this?  Should we proceed with the Sieve
> document as it is, with the addrbook URI?  Or do we still need more
> discussion?  We're otherwise ready to send the document to the IESG.
> 
> Barry
> _______________________________________________
> Uri-review mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/uri-review
>

---

From: Barry Leiba <[email-masked]>
Date: Fri, 13 May 2011 13:20:30 -0400

Graham said...
> Some alternative suggestions I have that might meet the immediate
> requirements of Sieve include:
> hand-written Sieve code, but feel that it is otherwise a technically
> reasonable approach.

We have taken this approach, along with using a shorthand indicator to
eliminate the need for the "urn:ietf:params:sieve" part when using
these URNs.  So we're withdrawing the request to register the
"addrbook" URI scheme.  Thanks, everyone, for taking the time to do
thoughtful and useful reviews.  Your comments improved the document,
even though we aren't ultimately using this URI scheme.

Barry