Re: Erik Kline's No Objection on draft-ietf-httpbis-header-structure-18: (with COMMENT)

[Mark Nottingham <[e-mail]>]

Hi Erik,

Thanks for the feedback; responses below.

> On 18 May 2020, at 10:20 am, Erik Kline via Datatracker <[e-mail]> wrote:
> 
> * It's documented as possible for field definitions to place constraints on
>  cardinality; what about constraints on order as well in certain situations?
> 
>  This came to mind again when I got to section 3.2 and read that index-based
>  access was required for dictionaries.  Is it possible for a field definition
>  to place requirements on the order of things in a dictionary?

Yes (although I think this would be somewhat unusual). When I looked at the text to address this, I found that talking about cardinality of dictionary members and parameters didn't make sense, because they're required to be unique. So, see:
  <https://github.com/httpwg/http-extensions/commit/d585c4b4339>

>  The phrase "ordered <thing>" appears repeatedly, and Appendix B has important
>  notes about order-preserving structures.  Did I perhaps miss some text early
>  on about this, or should/could this be highlighted in non-appendix text?

I'm struggling to find something to say; is "ordered" not clear enough? The text in the appendix was put there to make it more likely to be noticed. If you can suggest fitting text elsewhere, I'd be grateful. 

> * [ section 4.1.2 ]
>  Should items 3, 3.1, .. 5.2 be indented and renumbered under 2 after 2.1?

Already fixed in source; please confirm at <https://httpwg.org/http-extensions/draft-ietf-httpbis-header-structure.html#ser-dictionary>.

> * [ section 4.1.8 ]
>  Just to confirm: does serializing an empty byte sequence result in ::?
>  (assuming a context where the entire structured field would not otherwise
>  have been left unserialized)
> 
>  My reading of 4.2.7 is that :: would parse correctly as a 0-length byte
>  sequence.

Yes.

> [[ random ]]
> * The named ABNF productions are all sh-*, which I assume is for "structured
>  header".  I assume it's too late at this point, but sf-* for "structured
>  field" seemed like a logical choice to me.  Not the least bit important,
>  though!

That's a good point; we forgot to convert these when we moved to more correct terminology. I don't think it's too late; updated in <https://github.com/httpwg/http-extensions/commit/b9ef2abb333>.

Cheers,

--
Mark Nottingham   https://www.mnot.net/