ietf-nntp HDR replacement text

[Russ Allbery]

Clive D W Feather <clive at demon.net> writes:
> Russ Allbery said:

>> Hm.  Good point.  Having it just return an empty result is consistent
>> with how XHDR is currently implemented in INN and also seems consistent
>> with XOVER.  It's *not* consistent with the OVER text currently in the
>> draft, however, which states:

>>     If no articles are in the range specified, the server returns a 420
>>     error response.

>> I prefer that all of your examples above do the same thing,

> So do I.

>> and that all of them return a 423 error code.

> Note that it makes little difference to the client - both an error code and
> an empty list are easy to detect.

This is true.

I don't think we've yet reached any conclusions about this.  Could other
people please weigh in?  When all the articles in a specified range for
HDR or OVER are not present, should the server return an empty list, or an
error code?

Specifying an individual number and specifying a range should result in
the same behavior.

> I've got one practical issue. Can the server easily tell, at the start
> of processing the command, whether there are any articles in the range ? 
> For some implementations, sure. But for others I can see the code having
> to be along the lines of:

>     respond = true;
>     for (art = low_bound; art <= high_bound; art++)
>         if (article_exists (art))
>         {
>             if (respond)
>             {
>                 send_response (223);
>                 respond = false;
>             }
>             send_bits_of_article (art);
>         }
>     if (respond)
>         send_response (423);
>     else
>         send_final_dot ();

> instead of the much simpler:

>     send_response (223);
>     for (art = low_bound; art <= high_bound; art++)
>         if (article_exists (art))
>             send_bits_of_article (art);
>     send_final_dot ();

> Do we care ?

I'm not sure.

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