I have created a subscription to my Outlook calendar. When a specific instance of a recurring event is edited in Outlook, the notification that is sent to my notification url is for the series master event (not the particular instance that was updated).
I am trying to determine if the change was to the series or to a specific instance.
Is there any way to find out from the notification (or the series master) what caused the notification?
When you get the instances for an event (using the Graph API), the exceptions come back first (before the occurrences).
Therefore, if the series master did not change, I check to see if there are any instances where Type == "Exception". If there are, I delete them from outlook so they don't come back the next time I query for the event instances.
NOTE- I am still trying to find a solution to retrieve cancelledOccurrences, those instances of a recurring event that are deleted (or declined) from Outlook and therefore are not returned when querying the Graph API for event instances (https://learn.microsoft.com/en-us/graph/api/event-list-instances?view=graph-rest-1.0&tabs=http).