Schedule rake redmine:send_reminders to run periodically.

Dockerfile

@@ -1,5 +1,21 @@
 FROM redmine:5-bullseye
 
 COPY plugins/ plugins/
+COPY pre-entrypoint.sh /pre-entrypoint.sh
 
-RUN bundle check || bundle install
+ENV REDMINE_SEND_REMINDERS_DAYS=0 \
+	REDMINE_SEND_REMINDERS_CRON_EXPR="0 7 * * 1-5"
+
+RUN apt-get update && \
+	apt-get install -y cron && \
+	# Clean-up \
+	&& apt-get clean \
+	&& rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/* ~/.cache && \
+	# Remove default cron mess
+	rm -f /etc/cron.daily/* && \
+	rm -f /etc/cron.d/* && \
+	# Install plugin dependencies \
+	bundle check || bundle install && \
+	chmod +x /pre-entrypoint.sh
+
+ENTRYPOINT ["/pre-entrypoint.sh"]

pre-entrypoint.sh

@@ -0,0 +1,9 @@
+#!/usr/bin/env bash
+set -Eeo pipefail
+
+echo "0 7 * * * root cd /usr/src/redmine && rake redmine:send_reminders days=$REDMINE_SEND_REMINDERS_DAYS RAILS_ENV=production" > /etc/cron.d/redmine
+chmod 0644 /etc/cron.d/redmine
+
+set -- /docker-entrypoint.sh "$@"
+
+exec "$@"