[FR]: Add CalDAV Two-Way Sync Support

[Archetype444]

Feature Description

It would be great if Tasknotes could sync with a CalDAV server (e.g., Nextcloud, iCloud, or other CalDAV-compatible services).

Why this would be useful:

Keeps tasks and deadlines unified across devices and apps.

Allows integrating Obsidian notes with existing calendar setups.

Avoids duplicating effort by re-entering tasks in multiple places.

[aubreyz]

What happens when the notes are large - say 10K+
Each Caldav server sets its own limits

This would be a whole duplication of Sync, with all the issues that involves, but using a highly novel transfer mechanism...

[Archetype444]

ok maybe not the notes then, I just mean tasknotes tasks with scheduled dates

[aubreyz]

ok maybe not the notes then, I just mean tasknotes tasks with scheduled dates

But the tasks are the notes. That is the whole point of the plugin..... Without the note there is no task at all. Otherwise you might as well use obsidian tasks as

• [ ]

And what would happen to the rest of the note apart from the properties in this process - would it be eliminated, or would it somehow remember which body belonged to which header where that header (ie. the file title/name) had been changed (or deleted) elsewhere? It would need some sort of unique reference assigned to each note to join them up.

[callumalpass]

Thanks for the suggestion @Archetype444 . I'm hoping to add better calendar integration options. For the moment you can sync from an ics subscription, and regularly export an ics file.

[joellti]

I was looking for something similar but it doesn't have to be two-way sync. I just want to let Tasknotes pull events from an account on a private CalDAV server. The account requires user/pass to login. Right now I don't think Tasknotes can handle that yet but hope it can be supported soon.

[someromans]

The integration should be similar to the current Google Calendar integration. Events are editable and movable within Obsidian and then linked to a note. To overcome the uniqueness, maybe an identifier can be injected into the calendar event description.

[slipstyle]

I was considering creating something very similar for this... My goal was to have Home Assistant monitor my vault which is synced to its file-system, and parse the TaskNotes files to pull dates and create reminders via my Nextcloud calendar (by creating calendar events).

Using Home Assistant, I could receive events when either the calendar event or the note on disk was changed, and then compare and sync the change between the two. The note and the calendar event would need to share and store a unique ID that links them. This ID would be created upon seeing a new TaskNote that doesn't yet have an ID and calendar events would only be created when an ID is present...

In regards to syncing and sync conflicts, since my Obsidian Notes syncs files in near-real-time, so HA would be able to evaluate the changes in near-real-time too, so for my use case, I was fine with just letting Obsidian/TaskNotes be the master in the event of changes on both sides occurring during the same sync period.

I haven't gone through with actually implementing this, I have only gotten to the planning stage, partially because the ICS export feature now allows us to use the task's Estimated Time as the duration for the calendar events, which solved the biggest issue I had with it before, making the ICS export feature actually somewhat usable for my use case now (but it still not quite what I'd like, ie: it outputs tasks without any scheduled dates, for example).
Also, through the various TaskNotes updates recently, it seems like events and tasks created FROM connected CalDav are receiving a unique ID, so I was kinda hoping that this feature was already being implemented by more competent developers.
I also considered using the TaskNotes HTTP API for reminders (which was only considered because I was able to get Obsidian running 24/7 and synced locally on Home Assistant) however, parsing the notes directly from the FS seemed like a more universal method and I could build on it to do other things with other note types, so I dropped the HTTP API idea for now).

So instead of writing a whole new plugin for HA (something I've never done before), I'm going to first try and contribute some additional options to the ICS export feature, which seems more achievable, and would, at least for my use case, allow me to receive reminders for my Tasks, which is one of the only issues I have with Obsidian overall.

[zeknurn]

A great idea. Adding direct CalDAV support to TaskNotes would make it much simpler to keep multiple calendars in sync compared to using hacks relying on the ICS export feature.

[rk-kontur]

Yes, CalDAV two-way sync is essential. It opens up a LOT of possibilities.

[TomSmith-cvs]

could we support this FR via https://buymeacoffee.com or similar? I'd love to contribute something to this, because i try not to use Google and/or Microsoft services these days...

[ilMike42]

I've just started handling my tasks using this fantastic plugin and I have to say: the only piece missing for me is notifications/reminders. So I'd love to see CalDAV synchronization and fill the gap!