Google Apps Script Calendar Service: How to store and retrieve CalendarEvents using PropertiesService?

问题

I'm referring to this question.

As this code

var cal = CalendarApp.getCalendarById("Calendar Id");
var startTime = new Date(1850, 0, 1);
var endTime = new Date(2100, 0, 1);
var events = cal.getEvents(startTime, endTime);
Logger.log(events);
var sp = PropertiesService.getScriptProperties();
sp.setProperty("events", JSON.stringify(events));
events = JSON.parse(sp.getProperty("events"));
Logger.log(events);

returns:

Info [CalendarEvent, CalendarEvent, CalendarEvent, CalendarEvent, CalendarEvent]
Info [{}, {}, {}, {}, {}]

How to store and retrieve CalendarEvents (not only their IDs) using PropertiesService?

回答1:

Workflow:

I'm thinking the best option is to do the following:

• Retrieve event IDs from previously processed events, stored in Properties (variable oldEventIDs).
• Retrieve all events in the calendar with getEvents (variable allEvents).
• Filter the events in the calendar, removing the ones already in Properties (variable newEvents).
• After processing each new event, append the event ID to oldEventIDs.
• Store oldEventIDs in Properties.

Code sample:

var sp = PropertiesService.getScriptProperties();
var oldEventIDs = sp.getProperty("events").split(",");
var cal = CalendarApp.getCalendarById("Calendar Id");
var startTime = new Date(1850, 0, 1);
var endTime = new Date(2100, 0, 1);
var allEvents = cal.getEvents(startTime, endTime);
var newEvents = allEvents.filter(event => !oldEventIDs.includes(event.getId()));
newEvents.forEach(event => {
  // Event processing
  oldEventIDs.push(event.getId());
});
sp.setProperty("events", oldEventIDs.toString());

Notes:

• You have to call getEvents in each execution no matter what. I don't see how storing the events in Properties will let you avoid that. That's the method you use to get the events from the Calendar. In any case, I assume what's taking more time is the event "processing", about which no information was given.
• You would have to edit this sample so that the execution stops before reaching time limit.

Reference:

• Calendar.getEvents(startTime, endTime)
• Class PropertiesService

来源：https://stackoverflow.com/questions/61229940/google-apps-script-calendar-service-how-to-store-and-retrieve-calendarevents-us