to learn calendaring technologies better, as a pet project, I was trying to implement a Calendar server backen.
So far I have an email inbox(let's call a@test.com) linked to my code using webhook.
According to my experience when I create an event in Google Calendar with a@test.com, attendee2@outlook.com, attendee3@gmail.com in the invite list, I get an invite email in inbox and in return my code recieves the RAW invite email including ICS file content, It looks good till here.
If attendee@outlook.com responds with Yes/No/Maybe, entry in Google Calenar gets updated, attendee3@gmail.com's calendar entry also reflects the updated status. However my inbox recieves nothing hence my code doesn't get updated.
Reading more I encountered more concepts like iTIP etc. and also realised once Calendar entries are added to calendar, then Calendar programs/server interact with organiser and fellow attendees' servers using some mechanism other than email for sharing participation statuses.
Here, I am trying to find some explainer around how calendar servers interact with each other, and what analogous thing can be implemented in the code.
Note:
I checked this, and so far have got some sense that either CalDav server or client implicitly communicates the updates once initially invite is mailed. https://softwareengineering.stackexchange.com/questions/369001/implementing-caldav-server-vs-sending-icals-around