Dockerfile for building a release for Amazon Linux on EC2

Dockerfile

# Building an Phoenix (Elixir) Release targeting Amazon Linux for EC2
# By https://github.com/treygriffith
# Original by the Phoenix team: https://hexdocs.pm/phoenix/releases.html#containers
#
# Note: Build context should be the application root
# Build Args:
# OTP_VERSION - the OTP version to target, like 23.0
# ELIXIR_VERSION - the Elixir version to target, like 1.10.4
#
# If you have other environment variables in config/prod.secret.exs, add them as `ARG`s in this file

FROM amazonlinux:2 AS build

# https://gist.github.com/techgaun/335ef6f6abb5a254c66d73ac6b390262
RUN yum -y groupinstall "Development Tools" && \
    yum -y install openssl-devel ncurses-devel

# Install Erlang
ARG OTP_VERSION
WORKDIR /tmp
RUN mkdir -p otp && \
    curl -LS "http://erlang.org/download/otp_src_${OTP_VERSION}.tar.gz" --output otp.tar.gz && \
    tar xfz otp.tar.gz -C otp --strip-components=1
WORKDIR otp/
RUN ./configure && make && make install

# Install Elixir
ARG ELIXIR_VERSION
ENV LC_ALL en_US.UTF-8
WORKDIR /tmp
RUN mkdir -p elixir && \
    curl -LS "https://github.com/elixir-lang/elixir/archive/v${ELIXIR_VERSION}.tar.gz" --output elixir.tar.gz && \
    tar xfz elixir.tar.gz -C elixir --strip-components=1
WORKDIR elixir/
RUN make install -e PATH="${PATH}:/usr/local/bin"

# Install node
RUN curl -sL https://rpm.nodesource.com/setup_12.x | bash - && \
    yum install nodejs -y

# prepare build dir
WORKDIR /app

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

# set build ENV
ENV MIX_ENV=prod

# install mix dependencies
COPY mix.exs mix.lock ./
COPY config config
RUN mix do deps.get, deps.compile

# build assets
COPY assets/package.json assets/package-lock.json assets/
RUN npm --prefix ./assets ci --progress=false --no-audit --loglevel=error

COPY priv priv
COPY assets assets
RUN npm run --prefix ./assets deploy
RUN mix phx.digest

# compile and build release
COPY lib lib
# uncomment COPY if rel/ exists
# COPY rel rel
RUN mix do compile, release