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Re: [Fwd: Re: PUT vs strong ETags]

From: Julian Reschke <julian.reschke@gmx.de>
Date: Fri, 09 Dec 2005 10:50:49 +0100
Message-ID: <43995379.8050501@gmx.de>
To: Wilfredo Sánchez Vega <wsanchez@wsanchez.net>
CC: Jim Whitehead <ejw@soe.ucsc.edu>, Lisa Dusseault <lisa@osafoundation.org>, WebDAV <w3c-dist-auth@w3.org>

Wilfredo Sánchez Vega wrote:
> 
> On Dec 8, 2005, at 12:50 PM, Julian Reschke wrote:
> 
>> But with the current algorithm, the server can't return a strong ETag, 
>> unless it blocks updates of that content for one second. That may be 
>> unacceptable for some resources.
> 
>   Why couldn't it?  Just append a suffix or prefix?  What HTTPd does 

But where would it get the suffix from? If it had any way to store it, 
we wouldn't have the problem in the first place...

> right now is use the same ETag string but prefixes it with 'W/' to make 
> it weak.  This accomplishes the goal of making the first-second etag 
> different, but I think it should do that without making the tag weak, 
> which implies something that isn't the case.

It also accomplishes that clients will not be "forced" to sync multiple 
times within a second.

Consider a resource that changes 10 times per second, then is stable. A 
hypothetical client that does conditional GET requests will get an 
arbitrary version of the resource from within the first second, and then 
later the stable one. Seems to me that this is a good trade-off somehow.

Best regards, Julian
Received on Friday, 9 December 2005 10:29:37 GMT

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