Dockerfile

ARG ALPINE_VERSION
FROM alpine:${ALPINE_VERSION} AS build
ARG ALPINE_MIN_VERSION
ARG ERLANG_VERSION

# Important!  Update this no-op ENV variable when this Dockerfile
# is updated with the current date. It will force refresh of all
# of the base images and things like `apt-get update` won't be using
# old cached versions when the Dockerfile is built.
ENV REFRESHED_AT=2022-08-30 \
    LANG=C.UTF-8 \
    HOME=/opt/app/ \
    TERM=xterm \
    ALPINE_MIN_VERSION=${ALPINE_MIN_VERSION} \
    ERLANG_VERSION=${ERLANG_VERSION}

# Add tagged repos as well as the edge repo so that we can selectively install edge packages
RUN \
    echo "@main http://dl-cdn.alpinelinux.org/alpine/v${ALPINE_MIN_VERSION}/main" >> /etc/apk/repositories && \
    echo "@community http://dl-cdn.alpinelinux.org/alpine/v${ALPINE_MIN_VERSION}/community" >> /etc/apk/repositories && \
    echo "@edge http://dl-cdn.alpinelinux.org/alpine/edge/main" >> /etc/apk/repositories

# Upgrade Alpine and base packages
RUN apk --no-cache --update-cache --available upgrade

# Install bash and Erlang/OTP deps
RUN \
    apk add --no-cache --update-cache \
      bash \
      curl \
      ca-certificates \
      libgcc \
      lksctp-tools \
      pcre \
      zlib-dev

# Install Erlang/OTP build deps
RUN \
    apk add --no-cache --virtual .erlang-build \
      dpkg-dev \
      dpkg \
      gcc \
      g++ \
      libc-dev \
      linux-headers \
      make \
      autoconf \
      ncurses-dev \
      openssl-dev \
      unixodbc-dev \
      lksctp-tools-dev \
      tar

WORKDIR /tmp/erlang-build

# Download OTP
RUN \
    curl -sSL "https://github.com/erlang/otp/releases/download/OTP-${ERLANG_VERSION}/otp_src_${ERLANG_VERSION}.tar.gz" | \
      tar --strip-components=1 -xzf -

# Configure & Build
RUN \
    export ERL_TOP=/tmp/erlang-build && \
    export CPPFLAGS="-D_BSD_SOURCE $CPPFLAGS" && \
    ./otp_build autoconf && \
    ./configure \
      --build="$(dpkg-architecture --query DEB_HOST_GNU_TYPE)" \
      --prefix=/usr/local \
      --sysconfdir=/etc \
      --mandir=/usr/share/man \
      --infodir=/usr/share/info \
      --without-javac \
      --without-wx \
      --without-debugger \
      --without-observer \
      --without-jinterface \
      --without-et \
      --without-megaco \
      --enable-threads \
      --enable-shared-zlib \
      --enable-ssl=dynamic-ssl-lib && \
    make -j$(getconf _NPROCESSORS_ONLN)

# Install to temporary location
RUN \
    make DESTDIR=/tmp install && \
    cd /tmp && rm -rf /tmp/erlang-build && \
    find /tmp/usr/local -regex '/tmp/usr/local/lib/erlang/\(lib/\|erts-\).*/\(man\|doc\|obj\|c_src\|emacs\|info\|examples\)' | xargs rm -rf && \
    find /tmp/usr/local -name src | xargs -r find | grep -v '\.hrl$' | xargs rm -v || true && \
	find /tmp/usr/local -name src | xargs -r find | xargs rmdir -vp || true && \
    # Strip install to reduce size
	scanelf --nobanner -E ET_EXEC -BF '%F' --recursive /tmp/usr/local | xargs -r strip --strip-all && \
	scanelf --nobanner -E ET_DYN -BF '%F' --recursive /tmp/usr/local | xargs -r strip --strip-unneeded && \
    runDeps="$( \
		scanelf --needed --nobanner --format '%n#p' --recursive /tmp/usr/local \
			| tr ',' '\n' \
			| sort -u \
			| awk 'system("[ -e /tmp/usr/local/lib/" $1 " ]") == 0 { next } { print "so:" $1 }' \
	)" && \
    ln -s /tmp/usr/local/lib/erlang /usr/local/lib/erlang && \
    /tmp/usr/local/bin/erl -eval "beam_lib:strip_release('/tmp/usr/local/lib/erlang/lib')" -s init stop > /dev/null && \
    (/usr/bin/strip /tmp/usr/local/lib/erlang/erts-*/bin/* || true) && \
    apk add --no-cache \
        $runDeps \
        lksctp-tools

### Final Image

ARG ALPINE_VERSION
FROM alpine:${ALPINE_VERSION}
ARG ALPINE_MIN_VERSION

MAINTAINER Paul Schoenfelder <paulschoenfelder@gmail.com>

ENV LANG=C.UTF-8 \
    HOME=/opt/app/ \
    # Set this so that CTRL+G works properly
    TERM=xterm \
    ALPINE_MIN_VERSION=${ALPINE_MIN_VERSION}

# Copy Erlang/OTP installation
COPY --from=build /tmp/usr/local /usr/local

WORKDIR ${HOME}

RUN \
    # Create default user and home directory, set owner to default
    adduser -s /bin/sh -u 1001 -G root -h "${HOME}" -S -D default && \
    chown -R 1001:0 "${HOME}" && \
    # Add tagged repos as well as the edge repo so that we can selectively install edge packages
    echo "@main http://dl-cdn.alpinelinux.org/alpine/v${ALPINE_MIN_VERSION}/main" >> /etc/apk/repositories && \
    echo "@community http://dl-cdn.alpinelinux.org/alpine/v${ALPINE_MIN_VERSION}/community" >> /etc/apk/repositories && \
    echo "@edge http://dl-cdn.alpinelinux.org/alpine/edge/main" >> /etc/apk/repositories && \
    # Upgrade Alpine and base packages
    apk --no-cache --update-cache --available upgrade && \
    # Install bash and Erlang/OTP deps
    apk add --no-cache --update-cache \
      bash \
      libstdc++ \
      ca-certificates \
      ncurses \
      openssl \
      pcre \
      unixodbc \
      zlib && \
    # Update ca certificates
    update-ca-certificates --fresh

CMD ["bash"]