Re: A question on Versioning-unaware clients

Jim Whitehead (ejw@ics.uci.edu)
Wed, 4 Aug 1999 15:05:18 -0700


From: Jim Whitehead <ejw@ics.uci.edu>
To: ietf-dav-versioning@w3.org
Date: Wed, 4 Aug 1999 15:05:18 -0700
Message-ID: <NDBBIKLAGLCOPGKGADOJOEIMCCAA.ejw@ics.uci.edu>
In-Reply-To: <s7a72e2a.017@prv-mail25.provo.novell.com>
Subject: RE: A question on Versioning-unaware clients


> In draft-ietf-webdav-versioning-02 its mentioned that
>
> "Webdav versioning includes:
>
>   automatic versioning support for versioning-unaware clients"
>
> My question is:
>
> 1. Is this applicable to versioning-unaware clients which is
> accessing the file system thru' non-HTTP methods ( e.g. FTP )?

Actually, versioning-unaware clients are HTTP/DAV clients that don't
understand the versioning specification.  Its outside of our scope to
consider authoring via FTP.

However, I can imagine a server that, in addition to implementing DeltaV, it
also implements FTP, and as an implementation decision, performs automatic
versioning for FTP writes.  But, this doesn't affect the Delta-V or FTP
protocol -- it's an implementation decision for the server.

> 1.1 Do we expect all FTP servers ( and others ) to talk to the
> versioning component?

This is an implementation decision, but I'd expect most FTP/DAV server
combos to not provide automatic versioning for FTP resources.

>
> I don't think that will be acceptable solution at all..
>
> If no, then:
>
> 1.2 how does this work? If a versioning-aware client did a
> CHECKOUT on a file and versionig-unaware-non-HTTP client wants to
> open the file in "read-write" mode? Will this operation fail?

There are several choices here:

a) do a second checkout (allow parallel development)
b) fail the second checkout (allow only single line of development)

> Whatever is the case, spec is very unclear here....

We should certainly say which choice we make... (i.e., we need to fix this
in the spec.)

- Jim