Subject: Re: Optional Backpointers from Targets to References

From: Jim Amsden <[email-masked]>
Date: Tue, 15 Sep 1998 21:49:50 -0400

But client applications relying on the option won't interoperate with servers
that don't support it, so there isn't interoperability across WebDAV servers. I
suggest a better solution is for those servers built on repository managers
that can or need to support backpointers likely have specific client
applications that choose to use them. These clients should use and maintain
their own dead properties for this application specific function. That's what
properties are for. This is really an issue of factoring out variability,
separating it from the common protocol, and allowing client applications to
implement and exploit it as necessary.

Servers are also free to maintain whatever state they require in their
persistent repositories in order to maintain their integrity. This does not
need to, and often should not be exposed to client applications.

Having said all this, I'm not all that opposed specifically to backpointers
etc. I'm just concerned that WebDAV is rapidly reaching its complexity limit
and we should make every effort to make sure we are only adding what is
absolutely necessary. Servers are free to advertise their added value through
additional live properties. But I don't think the protocol should attempt to
standardize on a bunch of optional ones, especially based on speculation of how
they might be used. Lets get some experience with DAV clients and servers
before we add this stuff.

[email-masked] on 09/15/98 08:19:24 PM
Please respond to [email-masked]
To: [email-masked], [email-masked]
cc:
Subject: Re: Optional Backpointers from Targets to References

At 04:27 PM 9/15/98 PDT, John Stracke wrote:
>Jim Amsden wrote:
>
>> 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.

---

From: John Stracke <[email-masked]>
Date: Thu, 17 Sep 1998 13:37:05 -0700

Jim Amsden wrote:

> applications that choose to use them.

Choke.  And what happens when one of these clients tries to coexist with a client
that doesn't support backpointers?

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