Developing an app where applicants schedule interviews with our team members through a third party service. Periodically we make API calls to the third party for any recent changes, generate an ICS file then email that file to our team member so they can store it in their Google Calendar.
BEGIN:VCALENDAR VERSION:2.0 PRODID:-//Google Inc//Google Calendar 70.9054//EN CALSCALE:GREGORIAN METHOD:REQUEST BEGIN:VEVENT DTSTART:20171001T180000Z DTEND:20171001T190000Z SUMMARY:Sample Event UID:5179167a74d55b6fbaf6193026af14de@example.io DTSTAMP:20171001T023000Z ORGANIZER:noreply@example.io SEQUENCE:0 END:VEVENT END:VCALENDAR
The issue I'm having is that when the team member clicks the "Add to Calendar" link that Google Mail generates. It ignores the UID I generated, 5179167a74d55b6fbaf6193026af14de@example.io, and creates it's own: 20d19q1acurfub15pe94hb1b7s@google.com.
Because of this, when updates are made to the event the UID is not the same as Google is storing, therefore it creates a whole new event rather than updating the existing event. In the example below the event was moved 1 hour ahead:
BEGIN:VCALENDAR VERSION:2.0 PRODID:-//Google Inc//Google Calendar 70.9054//EN CALSCALE:GREGORIAN METHOD:REQUEST BEGIN:VEVENT DTSTART:20171001T190000Z DTEND:20171001T200000Z SUMMARY:Sample Event UID:5179167a74d55b6fbaf6193026af14de@example.io DTSTAMP:20171001T023224Z ORGANIZER:noreply@example.io SEQUENCE:1 END:VEVENT END:VCALENDAR
So now there are two events for the same interview with two different xxx@google.com UIDs.
I have found that if I import the ICS file directly, instead of using the "Add to Calendar" link, then the UID is preserved as originally created and updating/cancelling works as expected. Since the process of importing events in Google Calendar isn't the easiest workflow and the large volume of events we're expecting, I'm hoping to retain the "Add to Calendar" method.
Any suggestions on what I'm doing wrong here?
