WebDAV Advanced Collection Requirements

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WebDAV Advanced Collection Requirements

• Redmond, June 16, 1998

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Terminology

• Referential Member Resource A member resource
  that has no content of its own, but rather is a
  reference to another resource
• Target Resource The resource referenced by a
  referential member of a collection
• Strong Reference A reference whose referential
  integrity is guaranteed by the server
• Weak Reference A reference whose referential
  integrity is not guaranteed by the server

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Referential Members (1)

• 3.1.1 The same resource may be referenced by
  referential members of multiple collections.
• 3.1.2 The same resource may be referenced by more
  than one referential member of the same
  collection.
• 3.1.3 It is possible for the same resource to be
  an internal member of a collection and also to be
  referenced by one or more referential members of
  that same collection.

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Referential Members (2)

• 3.1.4 Operations on a referential member do not
  affect the resource it references except as
  needed to enforce referential integrity.
• 3.1.5 Operations on a resource do not affect
  references to it except as needed to enforce
  referential integrity.
• 3.1.6 For any referential member of a collection,
  it is possible to obtain the URI of the resource
  it references.

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Referential Members (3)

• 3.1.7 It is possible to add a referential member
  to a collection.
• 3.1.8 It is possible to remove a referential
  member from a collection.
• 3.1.9 It is possible for a referential member of
  a collection to carry its own properties,
  distinct from those of the resource it refers to.
• 3.1.15 A referential member of a collection is
  itself a resource.

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Referential Members (4)

• 3.1.10 A listing of members of a collection
  shows both the internal members and the
  referential members.
• 3.1.12 For any member of a collection, it is
  possible to discover whether it is an internal or
  a referential member.

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Referential Members (5)

• 3.1.11 It is possible to request creation of a
  referential member that the server will guarantee
  to have referential integrity.
• 3.1.13 It is possible to discover whether a
  referential member is a strong reference or a
  weak reference.
• 3.1.14 It is possible to discover whether a
  resource is the target of a strong reference.

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Ordered Collections (1)

• 3.2.1 Ordering is sufficiently standardized that
  different applications and servers can operate on
  the same ordering without private agreements.
• 3.2.7 It is possible to order the members of a
  collection in a client-specified way, not
  necessarily based on property values.
• 3.2.2 A collection is not required to be
  ordered.
• 3.2.3 The semantics of an ordering are
  discoverable.

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Ordered Collections (2)

• 3.2.4 Each collection member must appear in the
  ordering exactly once.
• 3.2.8 Internal and referential members may be
  intermixed in the same ordering.
• 3.2.5 An ordering must not include any resources
  that are not members of the collection.
• 3.2.n Only one ordering can be attached to a
  collection.

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Ordered Collections (3)

• 3.2.6 When a client requests a listing of the
  members of a collection, this listing is returned
  in the order specified by the collection.

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Information

• Requirements draft is at
• http//www.ics.uci.edu/ejw/authoring/collection/d
  raft-ietf-webdav-collection-reqts-01.txt
• Author can be reached at
• slein_at_wrc.xerox.com