Subject: Re: Optional Backpointers from Targets to References

From: Jim Amsden <[email-masked]>
Date: Tue, 15 Sep 1998 19:20:30 -0400

This will require ACLs on individual properties, something many servers may not
do as it presents a significant administration burden compared to simple CRUD
ACLs. ACLs for every user, on every resource, for each resource property, for
every WebDAV method is not tractable. We are rapidly reaching a scaleability
problem.

[email-masked] on 09/15/98 05:51:01 PM
Please respond to [email-masked]
To: [email-masked]
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Subject: Re: Optional Backpointers from Targets to References

Jim Amsden wrote:

> And third, creating a
> reference to a resource will require modification of the target resource to
> update its properties

I don't believe that has to be a problem.  The ACLs can be set up so that they
specifically permit the backpointer property to be updated by the server.  (Come
to that, it's a live property, so write access may not mean very much in the
first place.)

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From: John Stracke <[email-masked]>
Date: Tue, 15 Sep 1998 16:27:43 -0700

Jim Amsden wrote:

> This will require ACLs on individual properties,

Nope.  The backpointer update doesn't have to pass through the same code path as
PROPPATCH; it can call directly into the code that PROPPATCH calls, but bypass the
ACL check.

>> specifically permit the backpointer property to be updated by the server.
>
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From: Jim Davis <[email-masked]>
Date: Tue, 15 Sep 1998 17:18:36 PDT

>> This will require ACLs on individual properties,

I think there is some misunderstanding.  First, the property will be server
maintained, and hence exempt from access control.  Second, no one was
proposing to use ACLs on properties, except John, and I think he retracted
that.

Everyone agrees that backpointers have to be optional.  Not all server
implementors want this feature.  But some server implementors want it very
much.  For some of them, it is both useful and cheap.  It costs WebDAV
nothing to define this property, so that all such servers can be
interoperable.

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From: John Stracke <[email-masked]>
Date: Thu, 17 Sep 1998 13:36:07 -0700

Jim Davis wrote:

> Second, no one was

Yeah, that was just sloppy language on my part.

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