NNTP syntax (Was: [NNTP] Draft 26 pre-1)

[Clive D.W. Feather]

Ken Murchison said:
> I realize that its late in the game, but I've been staring at the ABNF 
> (again) and a couple things still bother me.

Thanks for this, even if I don't agree with what follows.

> First, the syntax doesn't specify that IHAVE and POST take an 
> encoded-article as an argument, and by extension, forces a similar 
> problem on AUTHINFO SASL and TAKETHIS.

Um, section 9.2:

     command-continuation = ihave-continuation /
           post-continuation
     
     ihave-continuation = encoded-article
     post-continuation = encoded-article
   
     encoded-article = multi-line-data-block
       ; after undoing the "byte-stuffing", this MUST match <article>

> So, I'd like to propose that a 
> paragraph such as the following be inserted between p.2 and p.3 of 
> section 3.1:

I've added a shorter paragraph just before "Each response MUST start ...":

    In some cases a command involves more data than just a single line.
    The further data may be sent either immediately after the command
    line (there are no instances of this in this specification, but
    there are in extensions such as [NNTP-STREAM]) or following a
    request from the server (indicated by a 3xx response).

> In conjunction with this, I'd propose that the ABNF for commands be 
> changed to something like the following (note that this is not complete 
> with all commands and terminals):

I don't see the point of this change; it actually makes things *less* clear
in my view. The bulleted list at the start of section 9 splits the
transaction into easily digested pieces for syntax purposes.

> Second, the syntax for responses is incorrect because it allows simple 
> responses such as 111 and 223 to be followed by a multi-line-data-block 
> and doesn't show which response codes go with each multi-line-response. 

This is the sort of semantic issue which I'm not sure is well-addressed
in the syntax, but I will think carefully about it.

> Additionally, shouldn't we indicate that the ARTICLE and BODY 
> responses (and perhaps others) need to be dot-stuffed

   9.3.3  Multi-line response contents
  
   This syntax defines the content of the various multi-line responses;
   more precisely, it defines the part of the response in the multi-line
   data block after any "byte-stuffing" has been undone.

> and that the 
> VERSION capability MUST be first in the capabilities response?

Good point. Fixed.

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Clive D.W. Feather  | Work:  <clive at demon.net>   | Tel:    +44 20 8495 6138
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