11. Free-busy queries

Freebusy queries are used to obtain freebusy information for a calendar-collection or principals. The result contains information only for events to which the current principal has sufficient access.

When targeted at a calendar collection the result is based only on the calendaring entities contained in that collection. When targeted at a principal freebusy URL the result will be based on all information which affect the principals freebusy status, for example availability.

The possible targets are:

• A calendar collection URL

• The XRD link with relation CalWS/current-principal-freebusy

• The XRD link with relation CalWS/principal-freebusy with a principal given in the request.

The query follows the specification defined in CalConnect CC/S 0903:2009 with certain limitations. As an authenticated user to the CalWS service scheduling read-freebusy privileges must have been granted. As an unauthenticated user equivalent access must have been granted to unauthenticated access.

Freebusy information is returned by default as xcalendar VFREEBUSY components, as defined by Internet-Draft draft-daboo-et-al-icalendar-in-xml-11. Such a component is not meant to conform to the requirements of VFREEBUSY components in IETF RFC 5546. The VFREEBUSY component SHOULD conform to section “4.6.4 Free/Busy Component” of IETF RFC 5545. A client SHOULD ignore the ORGANIZER field.

Since a Freebusy query can only refer to a single user, a client will already know how to match the result component to a user. A server MUST only return a single VFREEBUSY component.