Subject: Re: PaceIntrospection: Is another file format really needed?

From: Asbjørn Ulsberg <[email-masked]>
Date: Thu, 01 Jul 2004 20:38:00 +0200

On Wed, 30 Jun 2004 22:58:00 -0400, Beecher Greenman  
<[email-masked]> wrote:

>> There's  no real point in reusing atom:feed and atom:entry if what  
>> we're trying to  do with them is totally different from the element's  
>> original purpose.
>
> Except that introspection exactly fits the element's original purpose. I  
> offer the following as proof:

Ok, I see your points in that the Atom feed can be overloaded, and that  
its initial «intention text» wasn't clarifying enough to separate issues  
as introspection from regular resource-subscription. I think, however,  
that it is a huge difference. No one is going to subscribe to a  
introspection file. It will probably be updated at most once a year.  
There's no dynamic information in it, so there's no need for a tool to  
re-read it once it's first read.

The use-pattern of an introspection file is completely different from that  
of an ordinary subscription-based feed, so I don't think the <feed>  
element should be overloaded. It would be nice if you could provide an  
example (on the Wiki) of how you think such a introspection feed should  
look like, though.

-- 
Asbjørn Ulsberg         -=|=-        [email-masked]
«He's a loathsome offensive brute, yet I can't look away»

---

From: Beecher Greenman <[email-masked]>
Date: Thu, 01 Jul 2004 18:07:52 -0400

>>>>>> There's no real point in reusing atom:feed and atom:entry if 
what we're trying
 >>>>>> to do with them is totally different from the element's original 
purpose.
 >>
 >>>> Except that introspection exactly fits the element's original purpose.
 >>>> I offer the following as proof:

 >> Ok, I see your points in that the Atom feed can be overloaded, and 
that its initial
 >> «intention text» wasn't clarifying enough to separate issues as 
introspection from
 >> regular resource-subscription. I think, however, that it is a huge 
difference. No one
 >> is going to subscribe to a introspection file.

I admit to not seeing much use to it myself, but I wouldn't go to such 
extremes.

Let us suppose, for example, that some large site decided to keep a list 
of its
most popular services. Depending on a huge variety of factors, this list 
could very
well change daily. Suppose they wanted to offer this list in Atom. This 
seems like
a reasonable use for a syndication feed. But this is a list of sites, 
not a list
of articles; if a feed can be used for such a purpose, then a feed must 
also be
usable for introspection as well.

 >> It will probably be updated at most once a year.
 >> There's no dynamic information in it, so there's
 >> no need for a tool to re-read it once it's first read.

Again, I would not go to these extremes. It is true that a typical 
introspection
file will seldom be updated, and so there will not be much need for a 
tool to
re-read it once it is first read. If a tool should try, then the server 
can simply
send HTTP status code 304, 'Not Modified', just as it would for a 
syndication feed.

 >> The use-pattern of an introspection file is completely different 
from that of an
 >> ordinary subscription-based feed, so I don't think the <feed> 
element should be
 >> overloaded. It would be nice if you could provide an example (on the 
Wiki) of how
 >> you think such a introspection feed should look like, though.

I sent one example to the list already, which included capabilities. 
There has recently
been some discussion on this list arguing that a service list should not 
include
capabilities; my example can be pared down to do this as well.

I will add these both to the Wiki tonight; should I add it to 
PaceIntrospection,
or should I create a new pace for it, perhaps PaceServiceList, and drop 
this out of
PaceIntrospection altogether, since there is some debate on whether this 
should be
called "introspection" anyway?

- Beecher Greenman