Re: [Doh] A question on the mix of DNS and HTTP semantics

Stephane Bortzmeyer <bortzmeyer@nic.fr> Sun, 18 March 2018 16:56 UTC

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Date: Sun, 18 Mar 2018 16:53:57 +0000
From: Stephane Bortzmeyer <bortzmeyer@nic.fr>
To: Tony Finch <dot@dotat.at>
Cc: Ted Hardie <ted.ietf@gmail.com>, doh@ietf.org
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Subject: Re: [Doh] A question on the mix of DNS and HTTP semantics
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On Sun, Mar 18, 2018 at 10:11:41AM +0000,
 Tony Finch <dot@dotat.at>; wrote 
 a message of 62 lines which said:

> If the request is not HEAD/GET/POST, I return 405 Method Not Allowed
> with a browser-friendly body.
> 
> For POST requests with an unknown Content-Type, or GET requests with
> an unknown or missing `ct=` parameter, my server returns 415
> Unsupported Media Type with a browser-friendly body.
> 
> If the `dns=` parameter is missing from a GET request, the best
> response seems to be a browser-friendly 400 Bad Request.

> If the request's Accept: header doesn't allow
> `application/dns-udpwireformat` then the response should be a
> browser-friendly 406 Not Acceptable.

I agree with all this (and my hackathon-developed server does the
same) but, to follow Patrick McManus' idea of not restating everything
which is in HTTP, may be this could go in a non-normative appendix
such as "Implementation suggestions for non-HTTP experts"? With
lowercase "should" (specially for the last one: today, all the DoH
servers completely ignore Accept:)