Subject: Re: Input on request for link relation

From: Joe Gregorio <[email-masked]>
Date: Thu, 12 Nov 2009 17:18:39 +1100

On Thu, Sep 17, 2009 at 5:26 PM, Mark Nottingham <[email-masked]> wrote:
>
> On 16/09/2009, at 7:46 PM, Sam Johnston wrote:
>> Would it be possible then to support multiple references so that people
>> can see at a glance that a given relation is implemented as described in
>> multiple formats (rather than just the first format that happened to
>> register it)? May well not be worth the maintenance effort.
>
> How about adding a new field for references to more information about how a
> relation is used in a particular context (scoped by context media type)?
>
> E.g.,
>
> References regarding use in specific contexts:
>    text/html: [HTML5]
>    application/atom+xml: [RFC4287]
>

Yes, that sounds like a great idea. And vaguely familiar:

   http://lists.w3.org/Archives/Public/ietf-http-wg/2009JulSep/0699.html

   Thanks,
   -joe

---

From: Sam Johnston <[email-masked]>
Date: Thu, 12 Nov 2009 11:24:11 +0100

Another requirement I've stumbled on is the ability to group links.
For OCCI for example we want to give users the ability to create their
own actions (eg start, stop, restart) which will be advertised in the
HTTP headers and/or HTML HEAD. Currently each action has it's own
(opaque URI-based) rel so I have proposed class="action" be added for
grouping. Alternatively we could do rel="[http://purl.org/occi/]
action" and refine the action with one or more custom attributes (type
is not really appropriate here, nor when advertising protocol
endpoints like SSH and RDP which is anoter problem we ran into).

Pagination (eg first, last, next, previous) is another potentially
interesting group. Though the semantics are mostly predefined one
could envisage links like "next 100", "next 1000".

Sam on iPhone

---

From: Bill de hOra <[email-masked]>
Date: Thu, 12 Nov 2009 23:00:14 +0000

> (opaque URI-based) rel so I have proposed class="action" be added for

<link rel="stop@occi"

where "occi" is registered as for use by occi.

IOW allow the link registry to define rel scopes. The url or clash thing 
sucks and I don't want someone rolling up with a curies/qnames or some 
other XML macrocrap proposal for Atom.

Bill

---

From: Richard Salz <[email-masked]>
Date: Thu, 12 Nov 2009 18:20:31 -0500

> other XML macrocrap proposal for Atom.

Yeah, it would be a huge mistake to use something that's pretty much 
already guaranteed to be part of your Atom infrastructure.  Far better to 
create yet another distributed naming scheme.

Not.

        r$

--
STSM, WebSphere Appliance Architect
https://www.ibm.com/developerworks/mydeveloperworks/blogs/soma/

---

From: Sam Johnston <[email-masked]>
Date: Fri, 13 Nov 2009 01:28:49 +0100

Bill,

On Fri, Nov 13, 2009 at 12:00 AM, Bill de hOra <[email-masked]> wrote:

> sucks and I don't want someone rolling up with a curies/qnames or some other
> XML macrocrap proposal for Atom.
>

Thanks for the feedback - this is an interesting idea, however it's not
immediately clear to me how this helps us as one of our main motivations is
that others can create their own actions without bothering us or having to
be registered.

Basically we'd be trading one opaque identifier that doesn't need to be
registered for a shorter one that does and unless we were to accept
petitions from the public it would still not be possible to identify which
relations are "actions" anyway (consider "stop@occi" vs "quiesce@vendor").
The use case is the client saying "ok all these things are actions so even
if I don't understand what "quiesce" means I can still show a button to the
user in the right place".

A reversed, dotted domain format ala "org.occi-wg.action.stop" was something
else we considered but it too would not enjoy backwards compatibility with
existing implementations. It would however provide a simple solution to the
registry "problem" and could be easily differentiated from "short" relations
by the presence of "." and URIs by ":" (or some other regexps). That is to
say, it's compatible with what we have today, infinitely scalable,
distributed, concise, basically everything you want in an identifier.

Sam

---

From: Bill de hOra <[email-masked]>
Date: Fri, 13 Nov 2009 01:50:17 +0000

> create yet another distributed naming scheme.

It would be. HTML5 would probably be done by now if it wasn't for RDFa 
curies.

Thanks for the sarcasm though, it amused me no end, although it's often 
more effective if you leave out the "Not" bit.

Bill