FROM golang:1.17 as build

RUN git clone https://github.com/coredns/coredns.git /coredns

COPY plugin.cfg /coredns/plugin.cfg.new
RUN mv /coredns/plugin.cfg.new /coredns/plugin.cfg

RUN cd /coredns && make

FROM debian:stable-slim as cert

RUN apt-get update && apt-get -uy upgrade
RUN apt-get -y install ca-certificates && update-ca-certificates

FROM scratch

COPY --from=cert /etc/ssl/certs /etc/ssl/certs
COPY --from=build /coredns/coredns /coredns

EXPOSE 53 53/udp
ENTRYPOINT ["/coredns"]