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

Tony Finch <> Sun, 18 March 2018 11:03 UTC

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Date: Sun, 18 Mar 2018 11:03:55 +0000
From: Tony Finch <>
To: Patrick McManus <>
cc: Ted Hardie <>,
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Subject: Re: [Doh] A question on the mix of DNS and HTTP semantics
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Patrick McManus <> wrote:
> we should have a look at section 4.6 of bcp56bis - which warns against
> defining a laundry list of error codes in application protocols like DoH.
> For each of these cases HTTP has an appropriate code, which can be consumed
> by other HTTP clients in the HTTP ecosystem to mean the same thing. There
> might be more than one way to express something at the HTTP layer and, as
> long as the consumers follow the HTTP definitions, that's ok and doesn't
> need specification by DoH.

Right, that makes sense. Regarding "more than one way to express
something", the DoH draft describes two fairly specific ways to express a
DoH request, so it seems to me that it would be right to be equally
specific about the error cases, as well as the success case. Maybe there
is some way to explain what to do without being as verbose as I was :-)

Re. Accept:

> so the server certainly has the option of just returning 200+wireformat.
> Realistically given the size of wireformat that's probably the right thing
> to do both paths seem legal.

Being lazy, I'm happy that you say I don't need to implement any Accept:
processing :-)

Thanks for the helpful reply!

f.anthony.n.finch  <>  -  I xn--zr8h punycode
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