Issue Summary

If you have Team Calendars with an Jira Event that uses JQL. You'll be unable to subscribe to the ics CalDav URL provided if a single events JQL search has an invalid content (i.e. a field that doesn't exist).

Steps to Reproduce

1. Create Team Calendar
2. Add Jira Issue Event with custom JQL that attempts to load a project with an issue/event that doesn't exist
3. Grab the ics CalDav URL
4. Attempt to navigate to the URL in the browser OR attempt to set up 2 way sync through mail client.

I attached the below video to show the behavior experienced:

• Screen Recording 2022-08-12 at 1.54.23 PM.mov 

Expected Results

Should be able to subscribe to a calendar with CalDav.

Actual Results

If you navigate to the URL you'll get the below message in the Browser Network Console:

Request URL: https://ispann3.atlassian.net/wiki/rest/calendar-services/1.0/calendar/export/subcalendar/private/c98e77fc27c91eaa57c7bb0a6bdd7f234d4fbcc0.ics
Request Method: GET
Status Code: 500 
Remote Address: 104.192.140.20:443
Referrer Policy: strict-origin-when-cross-origin

If you attempt to use the CalDav URL in a mail client it'll never sync.

Workaround

There are 2 possible ways to fix this:

• Update the Calendar events to use JQL that returns valid results

OR

• Delete the event (with the broken JQL) from the calendar