SyncPersonalCalendar

appsscript.json

{
  "timeZone": "America/New_York",
  "dependencies": {
    "enabledAdvancedServices": [
      {
        "userSymbol": "Calendar",
        "version": "v3",
        "serviceId": "calendar"
      }
    ]
  },
  "exceptionLogging": "STACKDRIVER",
  "runtimeVersion": "V8",
  "oauthScopes": [
    "https://www.googleapis.com/auth/calendar"
  ]
}

Code.gs

/**
 * Sync personal events with your work calendar.
 *
 * Setup:
 *  1. From your personal calendar, add your work account in Calendar Settings > Share with specific people, you need at least "See all event details" access
 *  2. Create an Apps Script project in your work Google account: https://script.google.com/u/0/home
 *  3. Add this file and the appsscript.json file and customize the email addresses and other variables.
 *  4. Add a trigger for the `sync` function:
 *     - Event source: From calendar
 *     - Event calendar details: Calendar updated
 *     - Calendar owner email: [your personal email address]
 *
 * @ref https://medium.com/@willroman/auto-block-time-on-your-work-google-calendar-for-your-personal-events-2a752ae91dab
 *
 * @todo create Out Of Office events when the API is available: https://issuetracker.google.com/issues/112063903
 * @todo Use sync token: https://developers.google.com/apps-script/advanced/calendar#synchronizing_events
 */

const { GuestStatus, Visibility } = CalendarApp;

const fromEmail = "personal@example.com"; // email of the personal calendar to pull events from
const toEmail = "you@work.example.com"; // work email
const daysOut = 30; // how many days in advance to monitor and block off time
const skipWeekends = true; // syncing should ignore events on weekends
const officeHours = {
  start: 8, // start hour (8am)
  end: 16, // end hour (4pm)
};
const label = 'Out of Office'; // label to prepend to copied events
const acceptCalendars = [fromEmail, 'friend@example.com']; // Only process events from these calendars (prevents spam)

function sync() {
  const toCal = CalendarApp.getDefaultCalendar();
  const fromCal = CalendarApp.getCalendarById(fromEmail);
  const today = new Date();
  const enddate = new Date(); enddate.setDate(today.getDate()+daysOut);
  const fromEvents = fromCal.getEvents(today,enddate);
 
  for (let i = 0; i < fromEvents.length; i++) {
    const ev = fromEvents[i];
    const startTime = ev.getStartTime();
    const endTime = ev.getEndTime();
    
    // Ignore events that don't come from the accepted calendars
    const fromEventCal = ev.getOriginalCalendarId();
    if (!acceptCalendars.includes(fromEventCal)) continue;

    // Ignore events that I have not responded YES to or am not the owner of
    // NOTE: Can't use getMyStatus() because that would only work for the main calendar (toEmail)
    // NOTE: If guestList is empty I guess it's my own event?
    const guestList = ev.getGuestList(true);
    if (guestList.length) {
      const myEvent = guestList.filter((guest) => {
        return guest.getEmail() === fromEmail || guest.getEmail() === toEmail;
      }).reduce((mine, guest) => {
        return mine || (guest.getGuestStatus() == GuestStatus.OWNER || guest.getGuestStatus() == GuestStatus.YES);
      }, false);
      if (!myEvent) continue;
    }
    
    // Ignore all-day events (for now)
    if (ev.isAllDayEvent()) continue;
    
    // Check if event is on weekend
    const dow = startTime.getDay(); // day of week
    if (skipWeekends && (dow < 1 || dow > 5)) continue;
    
    // Check if event is during work day
    if (startTime.getHours() >= officeHours.end || endTime.getHours() <= officeHours.start) continue;
    
    // If the secondary event has already been blocked in the primary calendar, ignore it
    let alreadyBooked = false;
    const existing = toCal.getEvents(startTime, endTime);
    for (let j = 0; j < existing.length; j++) {
      const ex = existing[j];
      if (ex.getStartTime().getTime() == startTime.getTime() && ex.getEndTime().getTime() == endTime.getTime()) {
        console.log(`Skipping event from ${fromEventCal} scheduled for booked timeslot on ${toCal.getId()}: ${ex.getStartTime().toISOString()}–${ex.getEndTime().toISOString()}`);
        alreadyBooked = true;
        break;
      }
    }
    if (alreadyBooked) continue;

    // Check if the timeslot is marked "busy" on my personal calendar
    const checkBusy = {
      items: [{id: fromEmail, busy: 'Active'}],
      timeMin: ev.getStartTime().toISOString(),
      timeMax: ev.getEndTime().toISOString(),
    };
    const busyResponse = Calendar.Freebusy.query(checkBusy);
    // If there are no entries in the busy array, don't add to work calendar
    if (busyResponse.calendars[fromEmail].busy.length === 0) {
      console.log(`Skipping event marked "free" from ${fromEventCal}: ${ev.getTitle()}`);
      continue;
    }

    const visibility = ev.getVisibility();
    const public = visibility == Visibility.PUBLIC;

    console.log(`Syncing ${public ? 'public' : 'private'} event from ${fromEventCal}: ${ev.getTitle()}`);
    
    const newEvent = toCal.createEvent(public ? ev.getTitle() : label, startTime, endTime);
    // alternative version below that copies the exact secondary event information into the primary calendar event
    // var newEvent = toCal.createEvent(ev.getTitle(),ev.getStartTime(),ev.getEndTime(), {location: ev.getLocation(), description: ev.getDescription()});  

    // Remove all notifications from new event
    newEvent.removeAllReminders();
  }
}