Subject: Re: [Doh] New query formats

From: Ben Schwartz <[email-masked]>
Date: Tue, 3 Apr 2018 14:53:45 -0400

This suggestion has now been implemented in draft-05.  Do you feel the new
text achieves your goal?

In particular, I will note the following sentences:

The DNS API server defines the URI used by the
> request through the use of a URI Template [RFC6570].  Configuration
> and discovery of the URI Template is done out of band from this
> protocol.

and

These examples use a DNS API service with a URI Template of
>    "https://dnsserver.example.net/dns-query{?dns}"

Based on this text, it seems to me that if a client is configured out of
band with a template of this kind, and the server is later upgraded to
support additional query forms, the client cannot exercise those forms
until after a new out-of-band configuration update, because it does not
have any instructions about how to map the new values into a URI.

This is in contrast to draft-04's URL-based configuration, which would
allow a client to attempt new query forms without requiring a configuration
update.

On Mon, Mar 26, 2018 at 4:30 AM, Stephane Bortzmeyer <[email-masked]>
wrote:

> On Thu, Mar 22, 2018 at 02:32:40PM +0000,
>  Martin Thomson <[email-masked]> wrote
>  a message of 45 lines which said:
>
> > 3. Specify that other parameters can be used to carry information
> > about queries.  Servers that find unknown query parameters MUST ignore
> > them.
> >
> > 4. Define a new registry for header field parameters.  (The URI
> > template would have covered this neatly, so you could avoid that.)
>
> Yes, RFC 6570 is the right way to specify these parameters.
>
> You can get some inspiration from my (old) DNS looking glass:
>
> http://www.bortzmeyer.org/dns-lg-usage.html
>
> _______________________________________________
> Doh mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/doh
>

---

From: Martin Thomson <[email-masked]>
Date: Wed, 4 Apr 2018 15:44:22 +1000

I don't know about Stephane, but I can live with this.

Yes, it kicks the can down the road a little with respect to new query
formats, but it doesn't foreclose on them.  And as I said, without a
discovery process we don't really have a good path to introducing new
query formats.

Note that mostly only applies to GET.  POST can use new content types
with all the costs associated with that, or it can do the same as
proposed for GET.

On Wed, Apr 4, 2018 at 4:53 AM, Ben Schwartz <[email-masked]> wrote:
> support additional query forms, the client cannot exercise those forms until
> after a new out-of-band configuration update, because it does not have any
> instructions about how to map the new values into a URI.
>
> This is in contrast to draft-04's URL-based configuration, which would allow
> a client to attempt new query forms without requiring a configuration
> update.
>