Watchtower

Watchtower is a tool for automatically updating running Docker containers. It monitors your containers and checks for updates to their images, allowing you to keep your services up-to-date without manual intervention.

docker-compose.yaml

services:
  watchtower:
    image: containrrr/watchtower:latest
    container_name: watchtower
    environment:
      # WATCHTOWER_DISABLE_CONTAINERS: "" # will ignore labels set. It is worth checking out labels as that can be a more scalabe solution (automatic)
      WATCHTOWER_SCHEDULE: "0 0 4 * * *" # check and update containers daily at 4:00 AM
      WATCHTOWER_CLEANUP: true # remove the old image after restarting a container with a new image
      WATCHTOWER_TIMEOUT: 30s # timeout before the container is forcefully stopped. When set, this option will change the default (10s) wait time to the given value
      WATCHTOWER_REMOVE_VOLUMES: true # remove all anonymous volumes from the container before restarting with a new image. Named volumes will not be removed!
      WATCHTOWER_HTTP_API_TOKEN: ${WATCHTOWER_HTTP_API_TOKEN} # sets an authentication token to HTTP API requests
      WATCHTOWER_HTTP_API_METRICS: true # enables a metrics endpoint, exposing prometheus metrics via HTTP. See Metrics for details.
      WATCHTOWER_NOTIFICATIONS: gotify
      WATCHTOWER_NOTIFICATION_GOTIFY_URL: ${WATCHTOWER_GOTIFY_URL}
      WATCHTOWER_NOTIFICATION_GOTIFY_TOKEN: ${WATCHTOWER_GOTIFY_TOKEN}
      WATCHTOWER_NOTIFICATIONS_HOSTNAME: "watchtower"
      TZ: "Europe/Zurich"
    ports:
      - 8081:8080
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock
    restart: unless-stopped

Configuration

You can configure Watchtower by setting environment variables in the docker-compose.yaml file. The example above includes several common configurations, such as scheduling updates, cleaning up old images, and enabling notifications via Gotify.

Usage

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References

• Watchtower