Support CalDAV Calendar Event Color Sync

[ToToR65]

Hello,
I wonder if it was possible to have Event Color Sync for external CalDAV calendar. It was made possible for Google Calendar only in Support Google Calendar Event Color Sync #427 but I would like to have this function for my Baikal/NextCloud external calendar if it's possible.
Great work. Thank you.

[ulsklyc]

Event colour sync for CalDAV already works, and has since v0.84.0 - it is not Google-only. The ICS parser reads the RFC 7986 COLOR property and the sync gives it precedence over the calendar colour, so a CalDAV event that carries its own colour keeps it here instead of inheriting the calendar's.

The reason you don't see it is on the other end: Nextcloud and Baikal don't write that property. Baikal only stores what the client sends, and Nextcloud's calendar has no per-event colour to send. If you set COLOR on an event with a client that does support it, Yuvomi will pick it up on the next sync.

What genuinely is missing is the way back: Yuvomi does not write COLOR into the events it pushes out, so a colour set here stays here. That is worth doing, and I'll keep this thread open for it rather than closing as "already works".

[ToToR65]

By the way, I made test from my side on Yuvomi.

To be honest I use an old NextCloud instance for my calendar, that I mainly use it creating events with my DAVx⁵ and Fossify Calendar on Android. Then I exported events from NextCloud and imported through Fossify and DAVx⁵ to Baikal for test purpose. And with all of that, my events have different color I choose at creation and they have been kept on Baikal import. That is for my technical context.

And when I connect NextCloud and Baikal (which have the event color both ok on Fossify) to Yuvomi and assign them to my user on Yuvomi, all event got the user color on Yuvomi.
But if I assign to none user, the event from Baikal and NextCloud have the right color each on Yuvomi.

I don't understand well what I could do with user assignment on Yuvomi, I'm new to the app and keep on exploring it.

That's all I saw. I don't know yet if I need to assign calendar to user, but I would like to keep color event on calendar if I do if it's possible. From now, I'll just assign to none and see if I need a assignment later.

Thanks for your work 🙏👍

[ulsklyc]

You were right and I was wrong - thank you for testing it properly.

The colour sync works, exactly as you found: your events carry their own colour, Yuvomi reads it, and it shows correctly as long as the calendar is assigned to nobody. My earlier answer looked for the cause on the server side; it was here all along, in a display rule.

What was happening. Yuvomi resolved an event's colour as: assignee first, then the event's own colour, then the calendar colour. That rule threw two very different things into the same bucket. A calendar colour is inherited - every event in that calendar carries it, so it says nothing about any single one. An event colour is set on that event, either by hand here or as an RFC 7986 COLOR from your server. Treating both as equally overridable meant an explicit statement lost to a derived one.

Fixed on main, in the next release. The order is now: the event's own colour → the assignee → the calendar colour → neutral grey. An assigned event without its own colour still takes the person's colour, so nothing changes for calendars that never carried event colours. Who the event belongs to is still shown next to it in the avatar stack - that was always the way multiple assignees were communicated anyway, so the colour was never the only signal for it.

On user assignment - it is worth keeping, and it does more than colour. An assigned event shows that person's avatar on the entry, counts toward "who has something on today" in the overview and on the wall display, and can be filtered per member. Assigning a whole calendar to yourself is the usual setup when you sync a personal calendar into a shared household - it marks those events as yours without you having to touch each one. With this fix you can now do both: assign the calendar and keep the per-event colours.

Still open, as mentioned before: the way back. Yuvomi does not yet write COLOR into the events it pushes out, so a colour you set here will not reach Nextcloud or Baikal. That is tracked separately from this thread.

[ulsklyc]

Shipped in v2.36.0 - about half an hour after my comment above, which is why it did not say so at the time.

The order is now the event's own colour, then the assignee, then the calendar colour, then neutral grey. Your setup is the one this was measured against: a Nextcloud or Baikal calendar assigned to a member, whose events carry their own COLOR. Those colours now survive the assignment, and the avatar stack keeps saying who the event belongs to.

Thanks again for testing it properly and pushing back on my first answer. It was wrong, and the thread only got to the real cause because you did not leave it there.

One thing I said above needs correcting: I wrote that the way back was "tracked separately", and it was not - there is no such thread. Yuvomi still does not write COLOR into the events it pushes out, so a colour you set here will not reach Nextcloud or Baikal. If that matters for your setup, open a discussion for it and it will be tracked properly this time.

Closing this one as done.

[ToToR65]

Hello,

Wouaw, just tested right now, it seems to work.

Thanks A LOT for the amazing work you do. Don't worry about being wrong or right, what matter is to go ahead together ;)