DiscoverContextURL performs a DNS-based CardDAV service discovery as described in RFC 6352 section 11.

Filter returns the filtered list of calendar objects matching the provided query.

Match reports whether the provided CalendarObject matches the query.

ValidateCalendarObject checks the validity of a calendar object according to the contraints layed out in RFC 4791 section 4.1 and returns the only event type and UID occuring in this calendar, or an error if the calendar could not be validated.

Client provides access to a remote CardDAV server.

Handler handles CalDAV HTTP requests.

TODO if nothing more Caldav-specific needs to be added this should be merged with carddav.PutAddressObjectOptions.

Backend is a CalDAV server backend.

https://datatracker.ietf.org/doc/html/rfc4791#section-5.3.2.1.