Re: "Timeout" request header to tell server to wait for resource to become available

Brendan Long <self@brendanlong.com> Sun, 29 March 2015 15:38 UTC

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Date: Sun, 29 Mar 2015 10:34:14 -0500
From: Brendan Long <self@brendanlong.com>
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To: Martin Thomson <martin.thomson@gmail.com>
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Subject: Re: "Timeout" request header to tell server to wait for resource to become available
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I don't think the semantics I want are the same. RFC 7240's "wait"
indicates how long a client is willing to wait for a server to finish
processing, but what I'm looking for is a way to tell the server that we
want it to wait, even though it could respond now.

Maybe the "Wait-Until: available" or "Wait-Until: etags-change" variant
makes this more clear?

I don't think millisecond granularity of the timeout is particularly
important. I picked milliseconds because they're a common unit, but
seconds would be fine too. The main advantage of setting a timeout in
the header is that it makes altering clients to support this easier
(since they'll eventually get a valid response instead of a connection
error).

On 03/27/2015 08:46 PM, Martin Thomson wrote:
> 2015-03-27 17:13 GMT-05:00 Brendan Long <self@brendanlong.com>:
>> hTmftQ6t4pJNuAjYvl8l49hAE7QYpyVi0/bvxnbU27QG9agVq4g53cWouIU+9uKF
>> H39lF0vJJ8J3DQCXzgRirdaLoXZ+ZJZ0Jtu90FYE38afR763pPEVN02N6w7dgm+k
>> SI7bSJeep2dG7LzffTg+qzzpJeYJO2KnezE6YOIcDvoHxd80qJCb8zhqQkfSw0AR
>> OCVIgTG2x7f0i58Ls+/mcGSDnLWg1nZ8PACvuMte7V9B66fWvN9CCM8awcfdZ6w5
> I believe that what you want is accomplished by RFC 7240:
>
> Prefer: wait=5
>
> The units are perhaps suboptimal for your use case (seconds instead of
> milliseconds), but we might be able to make a change to support finer
> grained timing.