A simple docker-compose file for watchtower

Here is my docker-compose file for the watchtower container. It auto-updates other containers on the host, including itself (but that often fails for some reason). It uses a pre-configured GMail-adress to send notification mails.

version: "3"
services:
  watchtower:
    image: containrrr/watchtower
    restart: unless-stopped
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock
    ports:
      - 8844:8080
    container_name: watchtower1
    environment:
      - WATCHTOWER_HTTP_API_TOKEN=userandomstring
      - TZ=Europe/Berlin
      - WATCHTOWER_CLEANUP=true
      - WATCHTOWER_HTTP_API_UPDATE=true
      - WATCHTOWER_HTTP_API_PERIODIC_POLLS=true
      - WATCHTOWER_HTTP_API_METRICS=true
      - WATCHTOWER_NOTIFICATIONS=email
      - WATCHTOWER_NOTIFICATION_EMAIL_FROM=sender@mailadre.ss
      - WATCHTOWER_NOTIFICATION_EMAIL_TO=target@mailadre.ss
      - WATCHTOWER_NOTIFICATION_EMAIL_SERVER=smtp.gmail.com
      - WATCHTOWER_NOTIFICATION_EMAIL_SERVER_PORT=587
      - WATCHTOWER_NOTIFICATION_EMAIL_SERVER_USER=sender@mailadre.ss
      - WATCHTOWER_NOTIFICATION_EMAIL_SERVER_PASSWORD=secretkey # use an app password for this!
      - WATCHTOWER_NOTIFICATION_EMAIL_DELAY=2
      - WATCHTOWER_SCHEDULE=0 15 3 * * *
    hostname: "hostname"
    
Code language: YAML (yaml)

The WATCHTOWER_SCHEDULE env variable lets watchtower check for updates every day at 03:15.
Set the hostname to have a readable hostname in e-mail notifications.