Dockerfile

FROM ruby:2.5-slim
LABEL authors="Rob Wilkinson <rob@oddball.io>, Keifer Furzland <keifer@oddball.io>"

# Set some variables
ENV REPO_DIR /home/magnifier/src
ENV GEM_DIR /home/magnifier/gems

# Set application specific environment variables
ENV PORT=3000
ENV RAILS_ENV='production'
ENV RACK_ENV='production'
ENV NODE_ENV='production'
ENV RAILS_SERVE_STATIC_FILES='true'
ENV PATH="`ruby -e 'puts Gem.user_dir'`/bin:$PATH"


# We don't need documentashun
RUN echo "gem: --no-ri --no-rdoc" | tee /etc/gemrc

# Install curl so we can install yarn (ruby-slim doesn't have curl)
RUN apt-get update -yqq && \
  apt-get install -yqq --no-install-recommends curl gnupg2 && \
  curl -sL https://deb.nodesource.com/setup_10.x | bash - && \
  curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | apt-key add - && \
  echo "deb https://dl.yarnpkg.com/debian/ stable main" | tee /etc/apt/sources.list.d/yarn.list

# Update local packages and install dependencies, clean up to keep image small
RUN apt-get update -yqq && \
  apt-get install -yqq --no-install-recommends \
  build-essential \
  libpq-dev \
  nodejs \
  yarn \
  git && \
  apt-get clean autoclean && \
  apt-get autoremove -y &&\
  rm -rf \
  /var/lib/apt \
  /var/lib/dpkg \
  /var/lib/cache \
  /var/lib/log

# Create user and group, freeze GID/UID to avoid permission issues w/ shared
# data folders mounted across multiple machines
RUN groupadd magnifier --gid 8411 && \
  useradd --home /home/magnifier --create-home --shell /bin/false --uid 8412 --gid 8411 magnifier 

# Run stuff as magnifier 
USER magnifier

# Create app folde, symlink a persisted gem folder
RUN mkdir -p $REPO_DIR $REPO_DIR/tmp ${GEM_DIR}

# Change Working dir
WORKDIR $REPO_DIR

# Install gems
COPY --chown=magnifier:magnifier Gemfile Gemfile 
COPY --chown=magnifier:magnifier Gemfile.lock Gemfile.lock 
RUN bundle install --jobs 20 --retry 5 --deployment --path ${GEM_DIR}

# Install node-modules
COPY --chown=magnifier:magnifier package.json package.json 
COPY --chown=magnifier:magnifier yarn.lock yarn.lock 
RUN bundle exec yarn

# Now copy rest of app, minus what is is in .dockerignore
COPY --chown=magnifier:magnifier . .

# Inject RAILS_MASTER_KEY
ARG RAILS_MASTER_KEY
ENV RAILS_MASTER_KEY=$RAILS_MASTER_KEY

ARG database_host
ENV DATABASE_HOST=$database_host

ARG database_user
ENV DATABASE_USER=$database_user

ARG database_password
ENV DATABASE_PASSWORD=$database_password
# Compile static assets
RUN bundle exec rake webpacker:compile

# Provide a Healthcheck for Docker risk mitigation
HEALTHCHECK --interval=30s --start-period=5s \ 
  CMD curl -f http://localhost:3000 || exit 1

# Expose port
EXPOSE $PORT

# Entrypoint for running commands, like: `docker-compose run web rake db:setup`
ENTRYPOINT ["/home/magnifier/src/docker-entrypoint.sh"]


# Default command
CMD rails s -p $PORT -b 0.0.0.0