RSVP-able ICS Sync in Google Calendar

My calendar is my central place for managing my time and commitments — from all kinds of sources. And I love using RSVP to keep track of events that I actually plan to attend versus those that I just want to be aware of. Some of these event streams come as ICS feeds over event invitations. This is why I use the script I’m sharing here to automatically ingest these events into my Google Calendar and enable RSVP for them.

While this script is made specifically for TUM’s event title format, it might be helpful to you even if you’re not at TUM by adapting the title mutation logic.

1. Simply paste the script below into a new Apps Script Project.
2. Create a new calendar in your Google Calendar and copy its ID from the calendar settings (Calendar ID at the bottom), then hide it.
3. Update CALENDAR_ID in the script to the value you just copied. Update INVITE_CALENDAR_ID to the calendar id of your personal calendar (same procedure as before).
4. Update ICS_URL to the ICS feed you want to ingest.
5. Select and run the setupTrigger method in the top toolbar.

You will now be invited to events present in the ICS stream by your hidden calendar. Please note that responding to these invites is only for personal organization and will not send a response to the original organizer. ICS simply doesn’t support that.