ARG BASETAG=alpine
FROM postgres:$BASETAG

ARG GOCRONVER=v0.0.8
ARG TARGETOS
ARG TARGETARCH
RUN set -x \
	&& apk update && apk add ca-certificates curl \
	&& curl -L https://github.com/prodrigestivill/go-cron/releases/download/$GOCRONVER/go-cron-$TARGETOS-$TARGETARCH-static.gz | zcat > /usr/local/bin/go-cron \
	&& chmod a+x /usr/local/bin/go-cron \
	&& apk del ca-certificates

ENV POSTGRES_DB **None** \
    POSTGRES_DB_FILE **None** \
    POSTGRES_HOST **None** \
    POSTGRES_PORT 5432 \
    POSTGRES_USER **None** \
    POSTGRES_USER_FILE **None** \
    POSTGRES_PASSWORD **None** \
    POSTGRES_PASSWORD_FILE **None** \
    POSTGRES_EXTRA_OPTS '-Z9' \
    SCHEDULE '@daily' \
    BACKUP_DIR '/backups' \
    BACKUP_KEEP_DAYS 7 \
    BACKUP_KEEP_WEEKS 4 \
    BACKUP_KEEP_MONTHS 6 \
    HEALTHCHECK_PORT 8080

COPY backup.sh /backup.sh

VOLUME /backups

ENTRYPOINT ["/bin/sh", "-c"]
CMD ["exec /usr/local/bin/go-cron -s \"$SCHEDULE\" -p \"$HEALTHCHECK_PORT\" -- /backup.sh"]

HEALTHCHECK --interval=5m --timeout=3s \
  CMD curl -f "http://localhost:$HEALTHCHECK_PORT/" || exit 1