# Build CoreDNS from source
FROM golang:latest AS builder

RUN apt-get update && apt-get install -y git make && rm -rf /var/lib/apt/lists/*

WORKDIR /build
RUN git clone --depth 1 https://github.com/coredns/coredns.git .

# Build static binary
RUN CGO_ENABLED=0 make

# Runtime image
FROM ubuntu:latest

RUN apt-get update && apt-get install -y ca-certificates && rm -rf /var/lib/apt/lists/*

COPY --from=builder /build/coredns /usr/local/bin/coredns
COPY Corefile /etc/coredns/Corefile

EXPOSE 53/udp 53/tcp

ENTRYPOINT ["/usr/local/bin/coredns"]
CMD ["-conf", "/etc/coredns/Corefile"]