One of:

docker pull srittau/cron:latest-copy
docker pull srittau/cron:latest-onbuild

There are two variants of the image: onbuild and copy. The onbuild requires several files in your build directory:

• A crontab file. A sample crontab is included. Python modules can be run using the /app/run-module.sh script.
• A msmtprc configuration file. If you don't want to send mail, this file can be empty. A sample file is included.

In your Dockerfile:

FROM srittau/cron:3.11-onbuild

The copy variant requires you to copy your Python modules into the image yourself. In your Dockerfile:

FROM srittau/cron:3.11-copy

COPY ./crontab /etc/crontab
COPY ./msmtprc /root/.msmtprc

Copying the .msmtprc file is optional. By default, the image will not send mail.

Your Python modules should be copied into the /app/src directory in your image. You can also copy or mount a environment file to /app/env. Shell variables in this file are added to the environment before running your scripts.