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Re: HTTP 1.1 pipelining

From: S. Mike Dierken <mdierken@hotmail.com>
Date: Sat, 29 May 2004 00:54:40 -0700
To: "A Bagi" <ahmed.bagi@virgin.net>, "Ian Clelland" <ian@veryfresh.com>, <www-talk@w3.org>
Message-ID: <BAY16-DAV20zkjC29Yg0001f55b@hotmail.com>

The meaning of PUT in HTTP is that submitting the content more than once has
the same effect as submitting it once (it's in the HTTP spec). Hence, it is
idempotent. However, POST is not defined that way, it is not idempotent.

----- Original Message ----- 
From: "A Bagi" <ahmed.bagi@virgin.net>
To: "Ian Clelland" <ian@veryfresh.com>; <www-talk@w3.org>
Cc: "S. Mike Dierken" <mdierken@hotmail.com>
Sent: Friday, May 28, 2004 1:14 PM
Subject: Re: HTTP 1.1 pipelining


> Idempotence: the ability of a Document to be transmitted and accepted more
> than once with the same effect as being transmitted and accepted once.
This
> somehow does not mean no side-effects (web applications, GET)!
> Only idempotent requests can be pipelined, such as GET and HEAD requests
> with maximum scucess.  POST and PUT are dodgy business!!
> Ahmed Bagi
> Manchester
>
> ----- Original Message ----- 
> From: "Ian Clelland" <ian@veryfresh.com>
> To: <www-talk@w3.org>
> Cc: "S. Mike Dierken" <mdierken@hotmail.com>
> Sent: Friday, May 28, 2004 7:34 PM
> Subject: Re: HTTP 1.1 pipelining
>
>
> >
> > S. Mike Dierken wrote:
> >
> > > I'm looking into request pipelining & had a question about the kind of
> > > requests allowed.
> > > The RFC says only idempotent requests should be pipelined.
> > > This FAQ
> > > (http://www.mozilla.org/projects/netlib/http/pipelining-faq.html) from
> > > Mozilla says PUT should not be used because it isn't idempotent.
> > > Except that it is. PUT is idempotent (repeatable with deterministic
> > > results).
> > >
> > > <>Which is it?
> >
> > I'm pretty sure that the Mozilla FAQ is wrong in this case. Perhaps the
> > author is confusing being idempotent with having no side-effects. You're
> > right that the semantics of PUT do make it acceptable for pipelining.
> >
> > Of course, given the number of web applications out there these days
> > which break idempotence even for GET requests, I'd be worried about
> > assuming that property for anything on the web.
> >
> >
> > Ian Clelland
> > <ian@veryfresh.com>
> >
>
>
>
Received on Saturday, 29 May 2004 04:03:19 GMT

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