Dockerfile

ARG ELIXIR_VERSION=1.18
ARG OTP_VERSION=27.3
ARG DEBIAN_VERSION=bookworm-20250929-slim
ARG BUILDER_IMAGE="hexpm/elixir:${ELIXIR_VERSION}-erlang-${OTP_VERSION}-debian-${DEBIAN_VERSION}"
ARG RUNNER_IMAGE="debian:${DEBIAN_VERSION}"

# Robusta: reuse the prebuilt pgdelta + libpg-query artifacts from the
# upstream supabase/realtime image instead of running the heavy
# pgdelta-builder stage (saves ~2GB peak RAM during the build).
FROM supabase/realtime:v2.96.0 AS pgdelta-source

FROM ${BUILDER_IMAGE} AS builder

ENV MIX_ENV="prod"

RUN apt-get update -y \
    && apt-get install curl -y \
    && apt-get install -y build-essential git \
    && apt-get clean

RUN set -uex; \
    apt-get update; \
    apt-get install -y ca-certificates curl gnupg; \
    mkdir -p /etc/apt/keyrings; \
    curl -fsSL https://deb.nodesource.com/gpgkey/nodesource-repo.gpg.key \
    | gpg --dearmor -o /etc/apt/keyrings/nodesource.gpg; \
    NODE_MAJOR=24; \
    echo "deb [signed-by=/etc/apt/keyrings/nodesource.gpg] https://deb.nodesource.com/node_$NODE_MAJOR.x nodistro main" \
    > /etc/apt/sources.list.d/nodesource.list; \
    apt-get -qy update; \
    apt-get -qy install nodejs;

# prepare build dir
WORKDIR /app

# install hex + rebar
RUN mix local.hex --force && \
    mix local.rebar --force

# install mix dependencies
COPY mix.exs mix.lock ./
COPY beacon beacon
RUN mix deps.get --only $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/${MIX_ENV}.exs config/
RUN mix deps.compile
COPY priv priv
COPY lib lib
COPY assets assets

# compile assets with esbuild and npm
RUN cd assets \
    && npm install \
    && cd .. \
    && 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

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

ENV SLOT_NAME_SUFFIX="${SLOT_NAME_SUFFIX}" \
    LANG="en_US.UTF-8" \
    LANGUAGE="en_US:en" \
    LC_ALL="en_US.UTF-8" \
    MIX_ENV="prod" \
    ECTO_IPV6="true" \
    ERL_AFLAGS="-proto_dist inet6_tcp"

# Robusta: upgrade base packages so security fixes published after the
# pinned debian snapshot are included (e.g. gnutls, openssl, python3.11).
RUN apt-get update -y && \
    apt-get upgrade -y --no-install-recommends && \
    apt-get install -y --no-install-recommends \
      libstdc++6 openssl libncurses5 locales iptables sudo tini curl awscli jq xz-utils && \
    apt-get clean && rm -rf /var/lib/apt/lists/*

# Robusta: pgdelta artifacts copied from the upstream realtime image.
COPY --from=pgdelta-source /usr/local/share/pgdelta/pgdelta.xz /usr/local/share/pgdelta/pgdelta.xz
COPY --from=pgdelta-source /usr/local/bin/pgdelta /usr/local/bin/pgdelta
COPY --from=pgdelta-source /build/node_modules/.bun/@libpg-query+parser@17.6.3/node_modules/@libpg-query/parser/wasm/libpg-query.wasm /build/node_modules/.bun/@libpg-query+parser@17.6.3/node_modules/@libpg-query/parser/wasm/libpg-query.wasm

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

WORKDIR "/app"

RUN chown nobody:root /app && chmod g=u /app && \
    mkdir -p /app/.pgdelta-cache && chown nobody:root /app/.pgdelta-cache && chmod g=u /app/.pgdelta-cache

COPY --from=builder --chown=nobody:root /app/_build/${MIX_ENV}/rel/realtime ./
COPY run.sh run.sh
# Robusta fork: make everything under /app group-accessible so OpenShift's
# arbitrary-UID model (random UID + supplemental gid 0) can read/execute
# the release and write to pgdelta-cache.
RUN chgrp -R 0 /app && chmod -R g=u /app
RUN ls -la /app
ENTRYPOINT ["/usr/bin/tini", "-s", "-g", "--", "/app/run.sh"]
CMD ["/app/bin/server"]