ARG DEBIAN_VERSION=bullseye-slim
FROM golang:1.9-alpine as confd
ARG CONFD_VERSION=0.16.0
ADD https://github.com/kelseyhightower/confd/archive/v${CONFD_VERSION}.tar.gz /tmp/
RUN apk add --no-cache \
    bzip2 \
    make && \
  mkdir -p /go/src/github.com/kelseyhightower/confd && \
  cd /go/src/github.com/kelseyhightower/confd && \
  tar --strip-components=1 -zxf /tmp/v${CONFD_VERSION}.tar.gz && \
  go install github.com/kelseyhightower/confd && \
  rm -rf /tmp/v${CONFD_VERSION}.tar.gz

FROM debian:${DEBIAN_VERSION}
COPY --from=confd /go/bin/confd /usr/local/bin/confd
RUN mkdir -p /start.d \
  && printf '#!/bin/bash\nset -e\n/usr/local/bin/confd -onetime -backend env\nrun-parts -v /start.d\nexec ${@}\n' > /entrypoint.sh \
  && mkdir -p /etc/confd/conf.d /etc/confd/templates \
  && chmod +x /usr/local/bin/confd /entrypoint.sh
ENTRYPOINT ["/entrypoint.sh"]