OOO Calendar Sync

Google Apps Script that syncs out-of-office events from team members' individual calendars into a shared team calendar. Based on Google's vacation calendar sample — see below for differences.

How it works

1. Pulls the member list from configured Google Groups (pde@vida.com, dev-offshore@vida.com)
2. Scans each member's calendar for OOO events (looking for outOfOffice event types with keywords like "pto", "ooo", "out of office")
3. Imports matching events into the shared team calendar, prefixed with the username (e.g. [jane.doe] OOO - Vacation)
4. Only syncs events that are at least 6 hours long and up to 3 months in the future
5. Uses incremental sync — on subsequent runs, only checks events modified since the last run (within a 7-day window)

Runs on a time-based trigger every 5 minutes.

Files

File	Description
Code.js	Main sync logic — group member lookup, event filtering, and calendar import
CalendarTrigger.js	Experimental calendar-change triggers (not actively used)
appsscript.json	Apps Script project manifest (runtime config, scopes, advanced services)

Setup

Prerequisites

• A Google Workspace account with access to the target Google Groups
• A shared Google Calendar to import events into
• The Calendar Advanced Service enabled in the Apps Script project

Configuration

In Code.js, set these constants:

• TEAM_CALENDAR_ID — the ID of the shared team calendar
• GROUP_EMAIL — email address(es) of the Google Group(s) containing team members
• KEYWORDS — event summary keywords to match
• MONTHS_IN_ADVANCE — how far ahead to scan

First run

Run the setup() function from the Apps Script editor to create the time-based trigger and run the initial sync.

Development

This project uses clasp to sync between the local repo and Google Apps Script.

npm install -g @google/clasp
clasp login
clasp pull    # download latest from Apps Script
clasp push    # upload local changes to Apps Script. Immediately live!

Differences from the Google sample

This project is based on Google's vacation-calendar sample. Key changes:

• Incremental sync guard — If lastRun is more than 7 days old, it resets to a full sync to avoid the Calendar API's "modification time lies too far in the past" error
• New-user detection — Tracks known users in script properties; when a new member joins a group, their first sync does a full scan instead of incremental
• Keyword filter in shouldImportEvent — The original imports all outOfOffice events unconditionally (the KEYWORDS constant is defined but unused). This version actually filters events by summary keywords (pto, ooo, out of office)
• Minimum duration filter — Only syncs OOO events that are at least 6 hours long (filters out short focus-time blocks, etc.)
• Attendee acceptance check — For events the user didn't create, only imports if the user has accepted the invite
• delete event.sequence in importEvent — Strips the sequence number before importing to avoid conflicts with the target calendar
• Removed ONLY_DIRECT_MEMBERS flag — The sample supports toggling between direct/indirect member lookup; this version always uses indirect (recursive) lookup
• Explicit OAuth scopes and Calendar advanced service — The sample's manifest has no scopes or advanced services declared; this version pins them in appsscript.json
• Error handling in getUsersFromGroups — Wraps each group lookup in try/catch so one inaccessible group doesn't break the entire sync
• findEvents error handling — Changed continue to break on API errors to prevent an infinite retry loop when pagination fails
• CalendarTrigger.js — Experimental code for per-user calendar change triggers (not used in production due to trigger limits)

Required OAuth scopes

• calendar.readonly — read team members' calendars
• calendar — write events to the shared calendar
• script.scriptapp — manage triggers
• groups — read Google Group membership