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RE: RFC2518 issue: requiring ETags (Atlanta wg mtg)

From: Julian Reschke <julian.reschke@gmx.de>
Date: Wed, 26 Feb 2003 02:27:14 +0100
To: "Lisa Dusseault" <lisa@xythos.com>, "'Clemm, Geoff'" <gclemm@rational.com>, "'Webdav WG'" <w3c-dist-auth@w3c.org>
Message-ID: <JIEGINCHMLABHJBIGKBCGEGAGJAA.julian.reschke@gmx.de>

Lisa,

I agree with the statement that etags are useful. Etags on their own are
useful. ETags in conjunction with locking are even more useful. I doubt
anybody disagrees.

The issue we've been debating recently whether this justifies to *require*
etags. My recent tests with IIS and Apache/Moddav show that upon a PUT, all
you get is a weak etag, which clearly demonstrates that it is non-trivial to
produce robust etags when your backend is a filesystem. So, IMHO, we really
*can't* require strong etags, and weak etags really do not help.

So yes, there must be a safe way for a client to discover the server's etag
support (supported live properties, allprop, propname and GET/HEAD behaviour
MUST match), but that's it.

If a client doesn't want to communicate with a resource that doesn't provide
strong etags, it certainly can (and should be able) to do so. I think that's
all RFC2518bis should say.

Julian

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Received on Tuesday, 25 February 2003 20:27:51 GMT

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