Dockerfile.rails-next

FROM ruby:2.7-slim-buster

WORKDIR /rails_app

RUN apt-get update && apt-get -y upgrade && \
    apt-get install --no-install-recommends -y \
    build-essential \
    git \
    libpq-dev \
    postgresql-client-11 \
    tmpreaper \
    && \
    apt-get clean

# set MRI memory allocator to mimic jemalloc memory savings
ENV MALLOC_ARENA_MAX=2

# set a default RAILS_ENV for the build scripts
# this is required for the `rake assets:precompile` script
# to write assets to target dir set in `config.assets.prefix`
ARG RAILS_ENV=production
ENV RAILS_ENV=$RAILS_ENV

ADD ./Gemfile.next /rails_app/
ADD ./Gemfile.next.lock /rails_app/

# ensure we use the rails-next gemfile setup to ensure we boot the upgraded libaries
ENV BUNDLE_GEMFILE=Gemfile.next

RUN bundle config --global jobs `cat /proc/cpuinfo | grep processor | wc -l | xargs -I % expr % - 1` && \
    bundle install

ADD ./ /rails_app

RUN (cd /rails_app && mkdir -p tmp/pids && rm -f tmp/pids/*.pid)
RUN (cd /rails_app && SECRET_KEY_BASE=1a bundle exec rake assets:precompile)

CMD ["/rails_app/scripts/docker/start.sh"]