checkSessions method
Implementation
FutureOr<int> checkSessions() {
var now = DateTime.now();
return expiredSessions(now).resolveMapped((expired) {
var expiredIDs = expired.map((e) => e.id).toList();
return _resolveSharedSessions()
.removeAll(expiredIDs)
.resolveWithValue(expired.length);
});
}