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diff --git a/vendor/sabre/dav/docs/caldav-ctag.txt b/vendor/sabre/dav/docs/caldav-ctag.txt deleted file mode 100644 index 4787ca260..000000000 --- a/vendor/sabre/dav/docs/caldav-ctag.txt +++ /dev/null @@ -1,336 +0,0 @@ - - - -Calendar Server Extension C. Daboo - Apple - May 3, 2007 - - - Calendar Collection Entity Tag (CTag) in CalDAV - caldav-ctag-02 - -Abstract - - This specification defines an extension to CalDAV that provides a - fast way for a client to determine whether the contents of a calendar - collection may have changed. - - -Table of Contents - - 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 2. Conventions Used in This Document . . . . . . . . . . . . . . . 2 - 3. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 3.1. Server . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 3.2. Client . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 4. New features in CalDAV . . . . . . . . . . . . . . . . . . . . 3 - 4.1. getctag WebDAV Property . . . . . . . . . . . . . . . . . . 4 - 5. Security Considerations . . . . . . . . . . . . . . . . . . . . 4 - 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 5 - 7. Normative References . . . . . . . . . . . . . . . . . . . . . 5 - Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . . 5 - Appendix B. Change History . . . . . . . . . . . . . . . . . . . . 5 - Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 6 - - - - - - - - - - - - - - - - - - - - - -Daboo [Page 1] - - CalDAV Proxy May 2007 - - -1. Introduction - - In CalDAV [RFC4791] calendar data is stored in calendar collection - resources. Clients need to "poll" calendar collections in order to - find out what has changed since the last time they examined it. - Currently that involves having to do a PROPFIND Depth:1 HTTP request, - or a CALDAV:calendar-query REPORT request. When a calendar - collection contains a large number of calendar resources those - operations become expensive on the server. - - Calendar users often configure their clients to poll at short time - intervals. So polling traffic to the server will be high, even - though the frequency at which changes actually occur to a calendar is - typically low. - - To improve on performance, this specification defines a new "calendar - collection entity tag" (CTag) WebDAV property that is defined on - calendar collections. When the calendar collection changes, the CTag - value changes. Thus a client can cache the CTag at some point in - time, then poll the collection only (i.e. PROPFIND Depth:0 HTTP - requests) and determine if a change has happened based on the - returned CTag value. If there is a change, it can then fall back to - doing the full (Depth:1) poll of the collection to actually determine - which resources in the collection changed. - - This extension also defines CTag's on CalDAV scheduling - [I-D.desruisseaux-caldav-sched] Inbox and Outbox collections. - - -2. Conventions Used in This Document - - The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", - "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this - document are to be interpreted as described in [RFC2119]. - - When XML element types in the namespaces "DAV:" and - "urn:ietf:params:xml:ns:caldav" are referenced in this document - outside of the context of an XML fragment, the string "DAV:" and - "CALDAV:" will be prefixed to the element type names respectively. - - The namespace "http://calendarserver.org/ns/" is used for XML - elements defined in this specification. When XML element types in - this namespace are referenced in this document outside of the context - of an XML fragment, the string "CS:" will be prefixed to the element - type names respectively. - - - - - - -Daboo [Page 2] - - CalDAV Proxy May 2007 - - -3. Overview - -3.1. Server - - For each calendar or scheduling Inbox or Outbox collection on the - server, a new CS:getctag WebDAV property is present. - - The property value is an "opaque" token whose value is guaranteed to - be unique over the lifetime of any calendar or scheduling Inbox or - Outbox collection at a specific URI. - - Whenever a calendar resource is added to, modified or deleted from - the calendar collection, the value of the CS:getctag property MUST - change. Typically this change will occur when the DAV:getetag - property on a child resource changes due to some protocol action. It - could be the result of a change to the body or properties of the - resource. - -3.2. Client - - The client starts off with an empty string as the initial value for - the cached CTag of a calendar or scheduling Inbox or Outbox - collection that it intends to synchronize with. - - When polling a calendar or scheduling Inbox or Outbox collection, the - client issues a PROPFIND Depth:0 HTTP request, asking for the CS: - getctag property to be returned. - - If the returned value of CS:getctag property matches the one - currently cached for the calendar or scheduling Inbox or Outbox - collection, then the collection contents have not changed and no - further action is required until the next poll. - - If the returned value of CS:getctag property does not match the one - found previously, then the contents of the calendar or scheduling - Inbox or Outbox collection have changed. At that point the client - should re-issue the PROPFIND Depth:1 request to get the collection - changes in detail and the CS:getctag property value corresponding to - the new state. The new CSgetctag property value should replace the - one currently cached for that calendar or scheduling Inbox or Outbox - collection. - - -4. New features in CalDAV - - - - - - - -Daboo [Page 3] - - CalDAV Proxy May 2007 - - -4.1. getctag WebDAV Property - - Name: getctag - - Namespace: http://calendarserver.org/ns/ - - Purpose: Specifies a "synchronization" token used to indicate when - the contents of a calendar or scheduling Inbox or Outbox - collection have changed. - - Conformance: This property MUST be defined on a calendar or - scheduling Inbox or Outbox collection resource. It MUST be - protected and SHOULD be returned by a PROPFIND DAV:allprop request - (as defined in Section 12.14.1 of [RFC2518]). - - Description: The CS:getctag property allows clients to quickly - determine if the contents of a calendar or scheduling Inbox or - Outbox collection have changed since the last time a - "synchronization" operation was done. The CS:getctag property - value MUST change each time the contents of the calendar or - scheduling Inbox or Outbox collection change, and each change MUST - result in a value that is different from any other used with that - collection URI. - - Definition: - - <!ELEMENT getctag #PCDATA> - - Example: - - <T:getctag xmlns:T="http://calendarserver.org/ns/" - >ABCD-GUID-IN-THIS-COLLECTION-20070228T122324010340</T:getctag> - - -5. Security Considerations - - The CS:getctag property value changes whenever any resource in the - collection or scheduling Inbox or Outbox changes. Thus a change to a - resource that a user does not have read access to will result in a - change in the CTag and the user will know that a change occurred. - However, that user will not able to get additional details about - exactly what changed as WebDAV ACLs [RFC3744] will prevent that. So - this does expose the fact that there are potentially "hidden" - resources in a calendar collection, but it does not expose any - details about them. - - - - - - -Daboo [Page 4] - - CalDAV Proxy May 2007 - - -6. IANA Considerations - - This document does not require any actions on the part of IANA. - - -7. Normative References - - [I-D.desruisseaux-caldav-sched] - Desruisseaux, B., "Scheduling Extensions to CalDAV", - draft-desruisseaux-caldav-sched-03 (work in progress), - January 2007. - - [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate - Requirement Levels", BCP 14, RFC 2119, March 1997. - - [RFC2518] Goland, Y., Whitehead, E., Faizi, A., Carter, S., and D. - Jensen, "HTTP Extensions for Distributed Authoring -- - WEBDAV", RFC 2518, February 1999. - - [RFC3744] Clemm, G., Reschke, J., Sedlar, E., and J. Whitehead, "Web - Distributed Authoring and Versioning (WebDAV) Access - Control Protocol", RFC 3744, May 2004. - - [RFC4791] Daboo, C., Desruisseaux, B., and L. Dusseault, - "Calendaring Extensions to WebDAV (CalDAV)", RFC 4791, - March 2007. - - -Appendix A. Acknowledgments - - This specification is the result of discussions between the Apple - calendar server and client teams. - - -Appendix B. Change History - - Changes from -01: - - 1. Updated to RFC4791 reference. - - 2. Added text indicating that ctag applies to schedule Inbox and - Outbox as well. - - Changes from -00: - - 1. Relaxed requirement so that any type of change to a child - resource can trigger a CTag change (similar behavior to ETag). - - - - -Daboo [Page 5] - - CalDAV Proxy May 2007 - - -Author's Address - - Cyrus Daboo - Apple Inc. - 1 Infinite Loop - Cupertino, CA 95014 - USA - - Email: cyrus@daboo.name - URI: http://www.apple.com/ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -Daboo [Page 6] - |