Re: WebDAV Versioning Scenarios

From: jamsden@us.ibm.com
Date: Wed, Mar 29 2000

  • Next message: Sankar Virdhagriswaran: "Re: WebDAV Versioning Scenarios"

    From: jamsden@us.ibm.com
    To: ietf-dav-versioning@w3.org
    Message-ID: <852568B1.002F99AF.00@d54mta03.raleigh.ibm.com>
    Date: Wed, 29 Mar 2000 03:39:52 -0500
    Subject: Re: WebDAV Versioning Scenarios
    
    
    
    
    
    I agree with Geoff. I only want to make sure we don't design workspaces is
    such a way that dynamic workspace would be ruled out, or significantly
    different than static workspaces. So that's why I would like to keep the
    revision selection rule in the workspace, even if the revisions are
    selected with an explicit REFRESH method. Dynamic workspace would be
    exactly the same except the REFRESH wouldn't be required an would be
    ignored.
    |------------------------+------------------------>
    |                        |   "Geoffrey M. Clemm"  |
    |                        |   <geoffrey.clemm@ratio|
    |                        |   nal.com>             |
    |                        |   Sent by:             |
    |                        |   ietf-dav-versioning-r|
    |                        |   equest@w3.org        |
    |                        |                        |
    |                        |   03/28/2000 11:54 PM  |
    |                        |                        |
    |------------------------+------------------------>
      >------------------------|
      |                        |
      |           To:          |
      |   ietf-dav-versioning@w|
      |   3.org                |
      |           cc:          |
      |           Subject:     |
      |   Re: WebDAV Versioning|
      |   Scenarios            |
      >------------------------|
    
    
    
    
    
    
    
    
       From: jamsden@us.ibm.com
    
       I think there is a real simple way to describe the new workspace
      semantics that is fully consistent and conpatible with existing
      semantics. It goes something like this:
    
       A workspace describes dynamic or variable a set of revisions. It
      represents a place where a client or group of clients does work by
      making changes to resources directed at some desired end result. A
      workspace has a revision selection rule that describes the revisions
      that were selected by the workspace creator. A workspace MAY
      dynamically update its contents based on changes in the revision
      selection rule, or changes to resources managed by the server, e.g.,
      creation of new versioned resources, labeling revisions, checking in
      working resources in an activity, updating a configuration,
      etc.
    
    The key problem here is the "MAY".  Basically, any MAY is a headache
    for a client writer, since it means the client writer can't count on
    that aspect of server behavior.  I believe advanced versioning is too
    complicated to introduce a "MAY" in something as central as revision
    selection.
    
    I do know of one high-end CM company that supports both dynamic
    and static workspaces (I work for it, in fact :-), so
    I can personally vouch for how hard it is to actually
    implement dynamic workspaces that support non-trivial version
    selection rules, and how much work it is to write clients that allow
    a user to sensibly deal with both dynamic and static workspaces.
    
    I believe the practical result will be some clients that support
    only static workspaces, some that support only dynamic, and most
    that won't support workspaces at all since they can't count on
    consistent semantics from servers.
    
    So as cool as dynamic revision selection is, I believe we should
    excercise self-restraint and commit to static revision selection
    for the first version of the versioning protocol.
    Once that is widely implemented, and implementors are just dying
    to do something more challenging (:-), I'd be happy to consider
    adding in dynamic revision selection.
    
    Cheers,
    Geoff