Docker cron env variables

crontab.txt

* * * * * bash -c ". /root/.env.sh; /app/bin/console some:symfony_task_here &> /tmp/app-jobs-offers-sync-active.log"

Dockerfile

FROM XXXX

#Install cron
RUN apt-get update; \
    apt-get install -y cron; \
    apt-get clean; \
    touch /var/log/cron.log

COPY crontab.txt /etc/cron.d/crontab
COPY run-cron.sh /usr/local/app/entrypoint/run-cron.sh

CMD ["/usr/local/app/entrypoint/run-cron.sh"]

run-cron.sh

#!/bin/bash

ENV_VARS_FILE="/root/.env.sh"

echo "Dumping env variables into ${ENV_VARS_FILE}"
printenv | sed 's/^\(.*\)$/export \1/g' > ${ENV_VARS_FILE}
chmod +x ${ENV_VARS_FILE}

echo "Applying crontab"
crontab /etc/cron.d/crontab

echo "Running crontab"
cron -f

printenv | sed 's/^(.*)$/export \1/g' > ${ENV_VARS_FILE}

This will be failed when there are any special characters in your environment variable values.

I suggest using the following piece of code to export environment variables.

eval $(printenv | awk -F= '{print "export " "\""$1"\"""=""\""$2"\"" }' >> /etc/profile)