Re: Server Push Error Codes

Martin Thomson <> Wed, 24 August 2016 05:35 UTC

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From: Martin Thomson <>
Date: Wed, 24 Aug 2016 15:30:28 +1000
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To: Mark Nottingham <>
Cc: HTTP Working Group <>
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Subject: Re: Server Push Error Codes
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These seem mostly reasonable.

On 24 August 2016 at 14:26, Mark Nottingham <> wrote:

We are looking to provide solutions that make this unnecessary (absent
outright errors), but I think that it's a good code to have.


This seems like it could be overly specific.  PUSH_NOT_ACCEPTABLE
might be used to cover Accept as well as Accept-Encoding.  Unless you
want both.

For content-encoding, it seems unlikely that the server will get this
wrong.  The server might reasonably assume that the value for
Accept-Encoding is constant and it will usually be right.  If not,
read on.

For Accept, a server might get it wrong, but it is probably the case
that the right machinery for determining whether a response is
acceptable isn't engaged when the push arrives.  That usually requires
a bunch of other context.  The same applies if Accept-Encoding isn't