# EGroupware CalDAV/CardDAV server and REST API

CalDAV/CardDAV is build on HTTP and WebDAV, implementing the following additional RFCs containing documentation of the protocol:
* [rfc4791: CalDAV: Calendaring Extensions to WebDAV](https://datatracker.ietf.org/doc/html/rfc4791)
* [rfc6638: Scheduling Extensions to CalDAV](https://datatracker.ietf.org/doc/html/rfc6638)
* [rfc6352: CardDAV: vCard Extensions to WebDAV](https://datatracker.ietf.org/doc/html/rfc6352)
* [rfc6578: Collection Synchronization for WebDAV](https://datatracker.ietf.org/doc/html/rfc6578)
* many additional extensions from former Apple Calendaring Server used by Apple clients and others

## Path / URL layout for CalDAV/CardDAV and REST is identical

One can use the following URLs relative (!) to https://example.org/egroupware/groupdav.php

- `/`                        base of Cal|Card|GroupDAV tree, only certain clients (KDE, Apple) can autodetect folders from here
- `/principals/`             principal-collection-set for WebDAV ACL
- `/principals/users/<username>/`
- `/principals/groups/<groupname>/`
- `/<username>/`             users home-set with
- `/<username>/addressbook/` addressbook of user or group <username> given the user has rights to view it
- `/<current-username>/addressbook-<other-username>/` shared addressbooks from other user or group
- `/<current-username>/addressbook-accounts/` all accounts current user has rights to see
- `/<username>/calendar/`    calendar of user <username> given the user has rights to view it
- `/<username>/calendar/?download` download whole calendar as .ics file (GET request!)
- `/<current-username>/calendar-<other-username>/` shared calendar from other user or group (only current <username>!)
- `/<username>/inbox/`       scheduling inbox of user <username>
- `/<username>/outbox/`      scheduling outbox of user <username>
- `/<username>/infolog/`     InfoLog's of user <username> given the user has rights to view it
- `/addressbook/` all addressbooks current user has rights to, announced as directory-gateway now
- `/addressbook-accounts/` all accounts current user has rights to see
- `/calendar/`    calendar of current user
- `/infolog/`     infologs of current user
- `/(resources|locations)/<resource-name>/calendar` calendar of a resource/location, if user has rights to view
- `/<current-username>/(resource|location)-<resource-name>` shared calendar from a resource/location
- `/mail/`   REST API only
- `/timesheet/`   REST API only
- `/smallpart/`   REST API only

Shared addressbooks or calendars are only shown in the users home-set, if he subscribed to it via his CalDAV preferences!

Calling one of the above collections with a GET request / regular browser generates an automatic index
from the data of an `allprop` PROPFIND, allow browsing CalDAV/CardDAV tree with a regular browser.

## REST API: using EGroupware CalDAV/CardDAV server with JSON
- [Addressbook](Addressbook.md)
- [Calendar](Calendar.md) 
  * currently recurring events are readonly, they are returned but can not be created or modified
- [InfoLog](Infolog.md)
- [Mail](Mail.md) 
  * currently only sending mails, 
  * opening interactive compose windows, 
  * view and reply to eml files and 
  * vacation handling
- [Timesheet](Timesheet.md)
- [ViDoTeach](https://github.com/EGroupware/smallpart/blob/master/doc/RESP-API.md)
- [Links and attachments](Links-and-attachments.md)
  * linking application entries to other application entries
  * attaching files to application entries
  * listing, creating and deleting links and attachments
- [Example iterating through a huge result-set](https://github.com/EGroupware/egroupware/blob/master/doc/REST-CalDAV-CardDAV/api-client.php#L55)
  * use empty sync-token GET parameter in first request
  * you can use the optional nresults GET parameter to control how many results you will get
  * if the response contains a "more-results" attribute with value true, request them with the given sync-token from the response

> For the REST API you always have to send an "Accept: application/json" header and for POST & PUT requests additionally 
> a "Content-Type: application/json" header, otherwise you talk to the CalDAV/CardDAV server and don't get the response you expect!

Following RFCs / drafts used/planned for JSON encoding of resources
* [rfc9553: JSContact: A JSON Representation of Contact Data](https://datatracker.ietf.org/doc/html/rfc9553) 
* [rfc9555: JSContact: Converting from and to vCard](https://datatracker.ietf.org/doc/html/rfc9555)
* [rfc8984: JSCalendar: A JSON Representation of Calendar Data](https://datatracker.ietf.org/doc/html/rfc8984)

### ToDos
- [x] Addressbook
  - [ ] update of photos, keys, attachments
- [X] InfoLog
- [X] Calendar (recurring events and alarms are readonly)
  - [ ] support creating and modifying recurring events and alarms
- [X] Mail
  - [ ] querying received mails
- [X] relatedTo, links and attachments, see [links sub-collection to add attachments and links to other application-entries](Links-and-attachments.md)
- [X] ProjectManager: only projects itself are currently supported
  - [ ] add, update & delete project-members
  - [ ] add, update & delete project-elements
  - [ ] add, update & delete mile-stones
  - [ ] add, update & delete price-lists
- [ ] storing not native supported attributes eg. localization