Cron image.

crond/.dockerignore

+*
+!crontab

crond/Dockerfile

+FROM docker:18.09 as docker
+
+FROM adarnimrod/cron as supersonic
+COPY --from=docker /usr/local/bin/docker /usr/local/bin/
+COPY --chown=root:root crontab /crontab
+USER root

crond/README.md

+# crond
+
+> Cron container image.
+
+## Description
+
+This container runs Cron jobs for training SpamAssassin's Bayesian classifier
+and for updating ClamAV's virus database. The jobs run in the other containers,
+so the `dockerd` socket is bind mounted to this container and the commands are
+executed via `docker exec` in the other containers. Thus, outside of the context
+of this setup this container doesn't make much sense.
+
+## License
+
+This software is licensed under the MIT license (see `LICENSE.txt`).
+
+## Author Information
+
+Nimrod Adar, [contact me](mailto:nimrod@shore.co.il) or visit my [website](
+https://www.shore.co.il/). Patches are welcome via [`git send-email`](
+http://git-scm.com/book/en/v2/Git-Commands-Email). The repository is located
+at: <https://www.shore.co.il/git/>.

crond/crontab

+@daily docker exec mail_clamd_1 clamd-update
+@daily docker exec mail_spamd_1 spamd-learn