Re: [squid-users] R: [squid-users] HTTP/1.0 417 Expectation failed

>In the case of 100-continue a 417 response means that 100
> Continue interim response can not be expected to be seen and the client
> needs to resend the request only using the delay heuristics when sending
> request entities (PUT/POST etc..), and then obviously without the
> "Expect: 100-continue".

What means "using the delay heuristics" ? Why it should be necessary to send
using delays ?
Heuristics ?!

Some client can crate request with both this header and http1.0 protocol ?!

----- Original Message -----
From: "Henrik Nordström" <henrik_at_henriknordstrom.net>
To: "Riccardo Castellani" <r.castellani_at_usl6.toscana.it>
Cc: "'Amos Jeffries'" <squid3_at_treenet.co.nz>; <squid-users_at_squid-cache.org>
Sent: Friday, February 19, 2010 9:15 PM
Subject: Re: [squid-users] R: [squid-users] HTTP/1.0 417 Expectation failed

> fre 2010-02-19 klockan 14:57 +0100 skrev Riccardo Castellani:
>> I ask if Squid previous versions ignored Expect header forwarding request
>> to
>> server.
>> But now why Squid code (2.7 version) detects this header and it handles
>> it
>> as error ? Why has this Squid behaviour been modified ?
>
> Because more and more of HTTP/1.1 is getting implemented.
>
> Part of getting HTTP/1.1 implemented is proper processing of Expect,
> which includes responding with 417 if the Expect condition can not be
> fulfilled.
>
> Any software sending Expect also need to be prepared to receive a 417
> response back as response to the expectation and deal with it
> accordingly. In the case of 100-continue a 417 response means that 100
> Continue interim response can not be expected to be seen and the client
> needs to resend the request only using the delay heuristics when sending
> request entities (PUT/POST etc..), and then obviously without the
> "Expect: 100-continue".
>
> Due to the amount of broken software out there not prepared to deal with
> 417 responses Squid-2.7 has a directive to disable 100-continue
> expectation processing. ignore_expect_100
>
> Regards
> Henrik
>
Received on Sat Feb 20 2010 - 10:11:18 MST