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[Fwd: Re: PUT vs strong ETags]

From: Julian Reschke <julian.reschke@gmx.de>
Date: Tue, 29 Nov 2005 22:12:01 +0100
Message-ID: <438CC421.3020600@gmx.de>
To: WebDAV <w3c-dist-auth@w3.org>


-------- Original Message --------

Wilfredo Sánchez Vega wrote:
>   Question for you.
>   Apache HTTPD emits a weak etag for a file resource if the timestamp on 
> the file is the same as the current time (one second accuracy) and a 
> strong etag otherwise.
>   The reason for that logic, as I understand it, is that because the 
> etag generation depends on the timestamp and that the file may change 
> multiple times within a one-second period, an etag generated from a 
> timestamp matching the current time isn't reliable.

Finally a good explanation.

>   But your post caused me to re-read the spec, and this logic doesn't 
> seem consistent with the spec.  The weak etag would be the same for all 
> changes in a one-second period but the documents may not be semantically 
> similar.  So that seems like a bug.  Perhaps HTTPD should instead omit 
> the etag in that case, since the etag isn't weak; it's simply not 
> correctly calculable using the timestamp.
>   That sound right?

I think this is correct, and getting this question answered is essential
on how the working group tackles the various (new) ETag issues in

May I forward this mail to the WebDAV mailing list?

Best regards, Julian
Received on Tuesday, 29 November 2005 21:14:02 UTC

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