Etesync Hosted Dav adapter throwing HTTP 500

[Zvezdin]

Hello,

Note: Skip the next three bullets, which are ranting about the centralisation of calendar software, if you just want the description of the issue.

I'd like to discuss the hosted DAV adapter as seen on EteSync's paid hosted service - let me know if this is the right place for it. I have been trying to setup smart scheduling for a really long time now, but there are three problems:

• Universally all scheduling services (Calendly being the biggest) exclusively support Google, Microsoft, and occasionally Apple calendars.
• If you want to use any of these scheduling services without calendar sync, you'd hope that the scheduling service would default to send you email calendar invitations when someone books with you and you'll manually import it in your calendar, and same for the booking user. You'd be very wrong - none of these services do this - they just send you an email with info on when the meeting is scheduled, and you're expected to manually add it to your calendar (same for the booking user on the other side).
• The one service which supports CalDAV integrations is Harmonizely (or what looks like a clone of it, simplymeet.me). However, it seems like Etesync's hosted Dav adapter is causing trouble.

Now for the actual issue, the DAV adapter seems slow and unstable - when I synced it locally with thunderbird, it started syncing, sent some events over, then threw HTTP 500 on a request after 603ms. Later, it again syncs some events, and ends with another 500. Similarly, Harmonizely just returns a generic message saying something is wrong with the calendar.

Any clue? It'd be great if we can find a convenient way to do smart scheduling, which is a must for any professional usecases.

[Zvezdin]

Some more background: I'm syncing calendar with 100-1000 events. Here's two of the requests which fail, both are on a url /my-username/collection-id/

with request data <?xml version="1.0" encoding="UTF-8"?> <sync-collection xmlns="DAV:"><sync-token/><sync-level>1</sync-level><prop><getcontenttype/><getetag/></prop></sync-collection> and response A server error occurred. Please contact the administrator.

The above request failed after Thunderbird had already read some data. It stopped retrieving data after that, and periodically started sending the following requests, which all fail:

Similarly:

with request data <?xml version="1.0" encoding="UTF-8"?> <D:propfind xmlns:D='DAV:' xmlns:C='urn:ietf:params:xml:ns:caldav' xmlns:CS='http://calendarserver.org/ns/'><D:prop><D:resourcetype/><D:owner/><D:current-user-principal/><D:current-user-privilege-set/><D:supported-report-set/><C:supported-calendar-component-set/><CS:getctag/></D:prop></D:propfind>