FROM eclipse-mosquitto:2 arg UID=1000 arg GID=1000 arg USER=unicorn RUN if [ ${USER} != "root" ]; then \ apk add shadow && \ groupadd -f -g ${GID} ${USER} && \ useradd -m -g ${USER} -u ${UID} ${USER}; \ fi RUN chown -R ${USER}:${USER} /mosquitto USER ${USER}