Re: REFUSED_STREAM and CANCEL

Martin Thomson <martin.thomson@gmail.com> Tue, 26 March 2013 20:17 UTC

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Date: Tue, 26 Mar 2013 13:16:15 -0700
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From: Martin Thomson <martin.thomson@gmail.com>
To: "William Chan (陈智昌)" <willchan@chromium.org>
Cc: HTTP Working Group <ietf-http-wg@w3.org>
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Subject: Re: REFUSED_STREAM and CANCEL
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On 26 March 2013 12:42, William Chan (陈智昌) <willchan@chromium.org> wrote:
> REFUSED_STREAM says it was refused before any processing happened.

The temporal distinction ("before any processing happened") isn't a
useful one.  "Do not want" and "do not want any more" are so finely
graded in distinction as to be meaningless.

More importantly, given that a stream can contain frames that mutate
session state, ALL frames need to be processed to some extent.  If
this is to mean that it never surfaced above the framing layer, I
don't believe that information is actionable.

> The
> client knows that it's safe to retry the SYN_STREAM later on [...]

Presumably not for the same stream ;)


Bottom line: what do I do differently in response to a refused stream
as opposed to a cancelled one?