deck-chores 0.2rc2

Job scheduler for Docker containers, configured via container labels.

deck-chores
===========

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

* Documentation: https://deck-chores.readthedocs.io/en/latest/
* 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 ``arm`` 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*:

.. code-block:: yaml

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 <https://apscheduler.readthedocs.io>`_ for managing jobs
* `cerberus <http://python-cerberus.org>`_ for processing metadata
* `docker <https://docker-py.readthedocs.io>`_ for Docker interaction
* `flake8 <http://flake8.pycqa.org/>`_, `mypy <http://mypy-lang.org>`_,
`pytest <http://pytest.org>`_ and `tox <https://tox.readthedocs.io>`_ for testing
* `Python <https://python.org>`_


Roadmap
-------

0.3
...

- parse time units for interval triggers
- handle a global limit on concurrent jobs
- print jobs when receiving SIGUSR1
- randomization of interval triggered events
- maybe add a randomize expression for cron triggers


0.4
...

- keep output of job executions
- a rudimentary web ui


Authors
-------

- Frank Sachsenheim (maintaining)


History
-------

0.2-rc2 (2017-08-05)
~~~~~~~~~~~~~~~~~~~~

* *changed*: arm builds base on `arm32v6/python <https://hub.docker.com/r/arm32v6/python/>`_
* *changed*: therefore ``arm32v6`` replaces the ``arm``-suffix in image tags
* *changed*: there are no more images that get tagged with ``latest-$architecture``

0.2-rc1 (2017-07-01)
~~~~~~~~~~~~~~~~~~~~

* *refactoring*: uses the Python Docker SDK 2 (#14)
* *removed*: ``ASSERT_FINGERPRINT`` environment variable
* *renamed*: ``DOCKER_DAEMON`` to ``DOCKER_HOST`` to comply with the SDK
* *fix*: check on fixed labels (#18 by @aeri4list)
* documentation updates


0.1 (2017-03-02)
~~~~~~~~~~~~~~~~

* *fix*: docker-py returns ``None`` for labels of images that were created with
older Docker versions (#7)

0.1.beta3 (2017-01-22)
~~~~~~~~~~~~~~~~~~~~~~

* *new*: there's now a build for arm architectures
* *new*: an architecture agnostic manifest is pushed to the image registry for
release images

0.1.beta2 (2016-12-08)
~~~~~~~~~~~~~~~~~~~~~~

* *new:* set log format per :envvar:LOG_FORMAT
* *new:* an options label to set behavioural flags
* *new:* containers can be identified as a service by configurable labels
* *new:* job definitions for further containers of a service are ignored
(default, opt-out can be configured)
* *new:* image labels can also be parsed for job definitions
(default, opt-out can be configured)

0.1.beta1 (2016-12-04)
~~~~~~~~~~~~~~~~~~~~~~

* First release with full documentation