Fresh: Keeping your docker stacks up to date

Fresh was written to scratch an itch. It works by querying the respective repositories for the various manifests in order to determine if the images have been changed. If so it can do a combination of things:

• Set the exitcode to indicate the freshness, 0 means up-to-date and 1 outdated.
• Pull the updated images with docker-compose, and optionally recreate the containers with docker-compose up.
• Run a script before and after updating, f.ex. to enable maintenance mode or update permission on volumes.
• Notify webhooks when updating. Currently only Slack and Mattermost are supported.

Fresh is designed to be invoked using cron or systemd timers, and as such provides a light-weight easy-to-use alternative to more complex toolkits.