[NNTP] Optional LIST commands (was: LIST EXTENSIONS (again))

[Russ Allbery]

Clive D W Feather <clive at demon.net> writes:
> Ken Murchison said:

>> I like the idea of advertising whether MODE READER is required and
>> which optional LIST commands are supported, but I don't see where our
>> new token needs to be used as part of this.

> These are features of the core protocol, not extensions. Therefore, in
> my opinion, they belong with the support information for the core
> extension.  Note how we have "OVER MSGID" rather than separate "OVER"
> and "OVER-MSGID" capabilities.

So, here's a question.  Why *aren't* they extensions?  If it's just
because they were in RFC 977, I don't think that's a very good reason;
we've already eliminated one command that no one used (SLAVE), and I'm
happy to take other little-used commands and move them into the extension
category.

Here's a proposal:  Why don't we make LIST NEWSGROUPS mandatory (pretty
much everyone implements it, even if they don't have any data to return,
and the case of not having any data to return is already supported in the
description of the command), and make LIST ACTIVE.TIMES, LIST
DISTRIB.PATS, and LIST DISTRIBUTIONS separate extensions?

(Actually, I'd be quite happy if we dropped LIST DISTRIBUTIONS entirely,
but that may be too much hassle at this point.  It's a rather pointless
command that could be replaced by a web page at sites that care.)

They're optional commands, we want to advertise them in LIST EXTENSIONS,
we have a well-defined way of doing that for actual extensions... I think
this would be the simplest approach.

>> Is it realistic to assume that if a server supports one of the optional
>> LIST commands, that it would support all of them?  I don't know,

> Nor do I.

They're unrelated.  Many servers support one of them and not the others.

-- 
Russ Allbery (rra at stanford.edu)             <http://www.eyrie.org/~eagle/>