ARG ELIXIR_VERSION=1.17.2
ARG OTP_VERSION=27.0.1
ARG DEBIAN_VERSION=bookworm-20240812-slim

ARG BUILDER_IMAGE="hexpm/elixir:${ELIXIR_VERSION}-erlang-${OTP_VERSION}-debian-${DEBIAN_VERSION}"
ARG RUNNER_IMAGE="debian:${DEBIAN_VERSION}"

FROM ${BUILDER_IMAGE} AS builder

# install build dependencies
RUN apt-get update -y \
  && apt-get install -y \
    build-essential \
    git \
    nodejs \
  && apt-get clean \
  && rm -f /var/lib/apt/lists/*_*

# prepare build dir
WORKDIR /app

# install hex + rebar
RUN mix do local.hex --force, local.rebar --force

# set build ENV
ARG BUILD_MIX_ENV=prod
ENV MIX_ENV=${BUILD_MIX_ENV}

# install mix dependencies
COPY mix.exs mix.lock ./
RUN mix deps.get --only ${BUILD_MIX_ENV}
RUN mkdir config

# copy compile-time config files before we compile dependencies
# to ensure any relevant config change will trigger the dependencies
# to be re-compiled.
COPY config/config.exs config/${BUILD_MIX_ENV}.exs config/
RUN mix deps.compile

COPY priv priv

COPY lib lib

COPY assets assets

# compile assets
RUN mix assets.deploy

# Compile the release
RUN mix compile

# Changes to config/runtime.exs don't require recompiling the code
COPY config/runtime.exs config/

COPY rel rel
RUN mix release

EXPOSE 4000

# start a new build stage so that the final image will only contain
# the compiled release and other runtime necessities
FROM ${RUNNER_IMAGE}

RUN apt-get update -y \
  && apt-get install -y \
    ca-certificates \
    libncurses5 \
    libstdc++6 \
    locales \
    openssl \
    tini \
  && apt-get clean \
  && rm -f /var/lib/apt/lists/*_*

# Set the locale
RUN sed -i '/en_US.UTF-8/s/^# //g' /etc/locale.gen \
  && locale-gen

ENV LANG en_US.UTF-8
ENV LANGUAGE en_US:en
ENV LC_ALL en_US.UTF-8

WORKDIR "/app"
RUN chown nobody /app

# set runner ENV
ARG BUILD_MIX_ENV=prod
ENV MIX_ENV=${BUILD_MIX_ENV}

# Only copy the final release from the build stage
COPY --from=builder --chown=nobody:root /app/_build/${BUILD_MIX_ENV}/rel/slax ./

USER nobody

# If using an environment that doesn't automatically reap zombie processes, it is
# advised to add an init process such as tini via `apt-get install`
# above and adding an entrypoint. See https://github.com/krallin/tini for details
EXPOSE 4000
ENTRYPOINT ["tini", "--"]
CMD ["/app/bin/server"]