cron.sh

#!/bin/bash -l
set -eu

# export all env vars to a file which is automatically sourced inside the cron subshell
# https://gist.github.com/athlan/b6f09977e2f5cf20840ef61ca3cda932
printenv | awk -F= '{print "export " "\""$1"\"""=""\""$2"\"" }' >>/etc/profile

if [[ ${SCHEDULE} == "NONE" ]]; then
	node dist/index.js
else
	# `-l` ensures that /etc/profile is picked up by the sh subshell
	# stdout redirect ensures logs are redirected to the parent process https://snippets.aktagon.com/snippets/945-how-to-get-cron-to-log-to-stdout-under-docker-and-kubernetes
	echo "${SCHEDULE} root sh -lc 'cd ${PWD} && /usr/local/bin/node ${PWD}/dist/index.js' > /proc/1/fd/1 2>&1" >>/etc/crontab

	# debian slim does not include cron by default, this must be installed via Dockerfile
	# additionally, busybox does *not* add the cron process, so we must use the debian cron package
	cron -L 8 -f
fi