WSD WG Attributes Task Force
14 Jul 2003
See also: IRC log
Attendees
Present:
Steve Graham GGF William Vambenepe Hewlett-Packard Umit Yalcinalp Oracle David Snelling GGF Jim Amsden IBM (Invited WebDAV expert)
Regrets:
Scribe: sgg
Contents
Jim Amsden Presents on WebDAV
There
were no slides presented with this material.
... WebDAV
is a mechanism of communication, its a protocol, not
an implementation
... WebDAV grew up out
of HTTP (an extension of HTTP for authoring resources)
... WebDAV predated
SOAP, Web services etc.
...WebDAV
is a repository integration for distributed authoring
... set of IETF specs
... see: www.webdav.org
... collaborative development: adds collections to manage namespaces
... WebDav
defines several facets:
... 1) a particular resource
called: collection, operations like creation (make)
... add/remove things from a
collection
umit: how to associate identity with a collection?
jim: the collection is
identified by a URI
... 2) metadata support:
properties
... out of source information
... information about a resource, that is not contained in the resource itself
... create, remove and query properties of a resource
... particularly source links to other resources
... properties support 3 (really 2?) new
methods
…... a) proppatch verb - allows name/value pairs
to be specified to a resource
……... set add or remove property values
……... name of a property is a uri
……... value is an XML fragment
……... WebDAV does not specify how
properties are stored or accessed
william: is there support for metaData on
attributes?
jim: no, granularity is
resources
jim: there was discussion about standardizing
property sets for some interoperability
…... b) propfind verb - access properties
……... which properties to find (including all properties)
……... specify a depth header (if applied to a collection -recurse down)
……... or request just the property names
……... note: getting members of a collection is implemented as a propfind
... 3) concurrency
control in distributed authoring
... eg simple resource locking
... locking is at resource level, not property level
... 4) security issues
... webdav uses digest authentication schemes
... access control is not in level 1 or level 2
... access control will be discussed after internationalization
... 5) internationalization
... uses XML heavily
... header size restrictions do pose some concerns
Other areas that WebDAV concern itself with:
... advanced collections (adds server side support for ordering of collections)
... access control: read and modify acls
…... granularity at resource level
…... discussed property ACLs but Jim is not
sure what the current standing is
... search for resources using a query language similar to XQL
…... selection based on property values or resource contents
…... search returns same thing as a propfind
verb
umit: how would a client formulate and post a query? what is the target?
jim: search method takes an
entity request body and a uri. uri specifies the context for the search.
... distributed
notification is a current discussion area, with some interest
…... MSFT has an extension to WebDAV for
distributed notification
... versioning extensions: allows versions of resources to be created
…... version histories and recovery mechanisms
... activities: context in which change is made
... configuration management: collecting together consistent, immutable set of
resources
... why
is webDAV important and how it is being used
…... Apache server is a WebDAV server
…... most of MSFT tools are webdav clients
…... use of WebDAV for Web services metadata
…... determine what the properties are through propfind
and changing through proppatch and searching through
the search
Summary of
Action Items
$Date: 2002/02/19