initialSync method
Get the display name and the ctag. This ctag works like a change id. Every time the ctag has changed, you know something in the calendar has changed too.
Implementation
Future<CalResponse> initialSync(String path, {int? depth, bool syncToken = true}) {
var syncTokenTag = '\n<d:sync-token />';
var body = '''
<d:propfind xmlns:d="DAV:" xmlns:cs="http://calendarserver.org/ns/">
<d:prop>
<d:displayname />
<cs:getctag />${syncToken ? syncTokenTag : ''}
</d:prop>
</d:propfind>
''';
return propfind(path, body, depth: depth);
}