From cdbfbbe7501dec976bf007b41111e99aa2251bdf Mon Sep 17 00:00:00 2001
From: Lennart <18233294+lennart-k@users.noreply.github.com>
Date: Fri, 2 Aug 2024 20:36:45 +0200
Subject: [PATCH] Update README.md

---
 README.md | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/README.md b/README.md
index e4f4d99..ab537e8 100644
--- a/README.md
+++ b/README.md
@@ -27,18 +27,27 @@ a calendar server
 - [ ] Testing such that I'm confident enough to use it myself :)
 - [ ] WebDAV sync extension [RFC 6578](https://www.rfc-editor.org/rfc/rfc6578)
   - [ ] implement getctag [see](https://github.com/apple/ccs-calendarserver/blob/master/doc/Extensions/caldav-ctag.txt)
+  - [ ] implement WebDAV If header
 - [ ] Ensure proper routing
 - [x] Trash bin
   - [x] Hiding calendars instead of deleting them
   - [ ] Restore endpoint
+- [ ] Frontend
 
 ## Relevant RFCs
 
 - Versioning Extensions to WebDAV: [RFC 3253](https://datatracker.ietf.org/doc/html/rfc3253)
+
   - provides the REPORT method
+
 - Calendaring Extensions to WebDAV (CalDAV): [RFC 4791](https://datatracker.ietf.org/doc/html/rfc4791)
 - Scheduling Extensions to CalDAV: [RFC 6638](https://datatracker.ietf.org/doc/html/rfc6638)
   - not sure yet whether to implement this
 - Collection Synchronization WebDAV [RFC 6578](https://datatracker.ietf.org/doc/html/rfc6578)
   - We need to implement sync-token, etc.
 - This is important for more efficient synchronisation
+
+## Sync-token
+
+- a returned version of a resource is marked with a sync token
+- the client can send the sync token to find out about changes after this sync token