ics export EXDATE invalid date-time #1102
Description
Checklist
- I can reproduce the bug with the latest version given here.
- I made sure that there are no existing issues - open or closed - to which I could contribute my information.
- I made sure that there are no existing discussions - open or closed - to which I could contribute my information.
- I have read the FAQs inside the app (Menu -> About -> FAQs) and my problem isn't listed.
- I have taken the time to fill in all the required details. I understand that the bug report will be dismissed otherwise.
- This issue contains only one bug.
- I have read and understood the contribution guidelines.
Affected app version
1.10.3
Affected Android/Custom ROM version
Android 16 / GrapheneOS 2026030201
Affected device model
Pixel 7
How did you install the app?
F-Droid / IzzyOnDroid
Which calendar service or provider do you use, if any?
No response
Which sync adapter app do you use for calendar synchronization, if any?
No response
Steps to reproduce the bug
- Menu > Settings > Export to ics file
- included export events, export tasks, export part entries too, selected one calendar
- Attempted to import the ics file via radicale's web interface.
Expected behavior
I expected that the fossify exported ics file would import successfully in radicale.
Actual behavior
Noted the error on the interface and the logs stating: '20250429' is not a valid DATE-TIME at the line with EXDATE.
I then opened an issue on radicale, assuming it was an issue with their import Kozea/Radicale#2008 but per the reading of the rfc https://icalendar.org/iCalendar-RFC-5545/3-8-5-1-exception-date-times.html it seems that the exported ics file might be invalid.
My novice reading of the rfc is that EXDATE can either be in the form EXDATE;VALUE=DATE:20250429, EXDATE;VALUE=DATE-TIME:19960402T010000Z, or EXDATE:19960402T010000Z but I'm not 100% confident.
After taking the exported ics and removing unrelated events, here is the minimal file:
BEGIN:VCALENDAR
PRODID:-//Fossify//NONSGML Event Calendar//EN
VERSION:2.0
BEGIN:VEVENT
SUMMARY:Chess ✨
UID:540b1f50c0674021ba838e3d602c0fb41742356467766
X-FOSSIFY-CATEGORY-COLOR:-16434009
CATEGORIES:Chess wizard
LAST-MODIFIED:20251205T074226Z
TRANSP:OPAQUE
DTSTART:20250401T210000Z
DTEND:20250401T210000Z
X-FOSSIFY-MISSING-YEAR:0
DTSTAMP:20260302T055208Z
CLASS:PUBLIC
STATUS:CONFIRMED
RRULE:FREQ=WEEKLY;INTERVAL=1;COUNT=9;BYDAY=TU
EXDATE:20250429
END:VEVENT
END:VCALENDAR
Using the icalendar validator https://icalendar.org/validator.html states that the file is valid so we attempted to submit an issue with their feedback form but it failed.
Screenshots/Screen recordings
No response
Additional information
No response