deck-chores

A job scheduler for Docker containers, configured via container labels.

• Documentation: https://deck-chores.readthedocs.io
• Image repository: https://hub.docker.com/r/funkyfuture/deck-chores
• Code repository: https://github.com/funkyfuture/deck-chores
• Issue tracker: https://github.com/funkyfuture/deck-chores/issues
• Free software: ISC license

Features

• define regular jobs to run within a container context with container and optionally with image labels
• use date, interval and cron-like triggers
• set a maximum of simultaneously running instances per job
• restrict job scheduling to one container per service
• multi-architecture image supports amd64 and armv7l platforms, no emulator involved

Example

Let's say you want to dump the database of a Wordpress once a day. Here's a docker-compose.yml that defines a job that will be handled by deck-chores:

version: '2'

services:
  wordpress:
    image: wordpress
  mysql:
    image: mariadb
    volumes:
      - ./database_dumps:/dumps
    labels:
      deck-chores.dump.command: sh -c "mysqldump --all-databases > /dumps/dump-$$(date -Idate)"
      deck-chores.dump.interval: daily

It is however recommended to use scripts with a proper shebang for such actions. Their outputs to stdout and stderr as well as their exit code will be logged by deck-chores.

Limitations

At the moment deck-chores is designed to run on a single Docker node, not within a cluster of these. Code and documentation contribution covering this are highly encouraged.

Acknowledgements

It wouldn't be as charming to write this piece of software without these projects:

• APScheduler for managing jobs
• cerberus for processing metadata
• docker-py for Docker interaction
• flake8, mypy, pytest and tox for testing
• Python

Roadmap

0.3

• parse time units for interval triggers
• handle a global limit on concurrent jobs
• print jobs when receiving SIGUSR1
• support for configuring APScheduler's jitter option on Cron- & IntervalTrigger

0.4

• keep output of job executions
• a rudimentary web ui

Authors

• Frank Sachsenheim (maintaining)
• aeri4list
• alpine-digger
• Brynjar Smári Bjarnason