--- version: "3.8" services: app: entrypoint: /docker-entrypoint.mailrelay.sh environment: - SMTP_HOST=${SMTP_HOST} - SMTP_PORT=${SMTP_PORT:-25} - MAIL_FROM=${MAIL_FROM} configs: - source: mstmp_conf target: /etc/msmtprc - source: entrypoint_mailrelay_conf target: /docker-entrypoint.mailrelay.sh mode: 0555 configs: mstmp_conf: name: ${STACK_NAME}_mstmp_conf_${MSMTP_CONF_VERSION} file: msmtp.conf.tmpl template_driver: golang entrypoint_mailrelay_conf: name: ${STACK_NAME}_entrypoint_mailrelay_${ENTRYPOINT_MAILRELAY_CONF_VERSION} file: entrypoint.mailrelay.sh.tmpl template_driver: golang