Automatically Delete Old Google Calendar Events

Here’s a script that deletes the old events on all your Google calendars.

All the code can be found on my GitHub.

https://github.com/zjrubin/clean_calendar

Background

I use Google Calendar to schedule and track my various commitments. I've been using Google Calendar since about 2014 and I've noticed that Google has tons of data on my day-to-day schedule and whereabouts. I decided to write this script to automatically delete old Google Calendar events because I don't want Google to have any more data on me than what is relevant for the services I use.

The Python Script

The business logic of the python script is straightforward. The main function gives us a high level overview of what the script does:

 1def main():
 2    creds = handle_authentication()
 3
 4    service = build("calendar", "v3", credentials=creds)
 5
 6    calendars = get_calendars(service)
 7
 8    for calendar in calendars:
 9        events = get_old_events(service=service, calendar_id=calendar["id"])
10
11        delete_events(service=service, calendar=calendar, events=events)

• handle_authentication() acquires authentication credentials to access your calendars. You will need to log into your Google account for the script to proceed.
• build() creates the service object that we can use to interact with the Google Calendar API
• get_calendars() gets a list of all the calendars you have write access to For each calendar, get_old_events() gets a list of all the events on that calendar that are 30 or more days in the past from today.
• delete_events() deletes each of the old events one-by-one. It also prints out the timestamp and summary of each event it deletes.

Setup & Running the script

The repository includes the file README.md that has information on how to setup and run the script. Please refer to this README for the most up-to-date information on how to setup and run this script.

README

Running the Script Automatically

In the repository I included clean_calendar.sh, a shell script to activate the python virtual environment with the required packages for the script and run the script:

1#!/usr/bin/env bash
2
3set -euo pipefail
4# set -x
5
6DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" >/dev/null 2>&1 && pwd)"
7source "$DIR/env/bin/activate"
8
9python3 "$DIR/clean_calendar.py"

This script assumes that the virtual environment is in env/ , a subdirectory of the repository.

I then added an entry to my crontab to call this shell script once a day:

1# Remove old Google Calendar events
20 15 * * * /home/zach/.dotfiles/scripts/user_scripts/clean_calendar/clean_calendar.sh

With this entry, cron will run this script to delete old Google calendar events once a day at 3PM.