# syntax = docker/dockerfile:1 # This Dockerfile is designed for production, not development. Use with Kamal or build'n'run by hand: # docker build -t my-app . # docker run -d -p 80:80 -p 443:443 --name my-app -e RAILS_MASTER_KEY=<value from config/master.key> my-app # Make sure RUBY_VERSION matches the Ruby version in .ruby-version ARG RUBY_VERSION=3.3.4 FROM docker.io/library/ruby:$RUBY_VERSION-slim AS base # Rails app lives here WORKDIR /rails # Install base packages RUN apt-get update -qq && \ apt-get install --no-install-recommends -y curl libjemalloc2 libvips sqlite3 && \ rm -rf /var/lib/apt/lists /var/cache/apt/archives # Set production environment ENV RAILS_ENV="production" \ BUNDLE_DEPLOYMENT="1" \ BUNDLE_PATH="/usr/local/bundle" \ BUNDLE_WITHOUT="development" # Throw-away build stage to reduce size of final image FROM base AS build # Install packages needed to build gems and node modules RUN apt-get update -qq && \ apt-get install --no-install-recommends -y build-essential git node-gyp pkg-config python-is-python3 && \ rm -rf /var/lib/apt/lists /var/cache/apt/archives # Install JavaScript dependencies ARG NODE_VERSION=21.7.3 ARG YARN_VERSION=1.22.22 ENV PATH=/usr/local/node/bin:$PATH RUN curl -sL https://github.com/nodenv/node-build/archive/master.tar.gz | tar xz -C /tmp/ && \ /tmp/node-build-master/bin/node-build "${NODE_VERSION}" /usr/local/node && \ npm install -g yarn@$YARN_VERSION && \ rm -rf /tmp/node-build-master # Install application gems COPY Gemfile Gemfile.lock ./ RUN bundle install && \ rm -rf ~/.bundle/ "${BUNDLE_PATH}"/ruby/*/cache "${BUNDLE_PATH}"/ruby/*/bundler/gems/*/.git && \ bundle exec bootsnap precompile --gemfile # Install node modules COPY package.json yarn.lock ./ RUN yarn install --frozen-lockfile # Copy application code COPY . . # Precompile bootsnap code for faster boot times RUN bundle exec bootsnap precompile app/ lib/ # Precompiling assets for production without requiring secret RAILS_MASTER_KEY RUN SECRET_KEY_BASE_DUMMY=1 ./bin/rails assets:precompile RUN rm -rf node_modules # Final stage for app image FROM base # Copy built artifacts: gems, application COPY --from=build "${BUNDLE_PATH}" "${BUNDLE_PATH}" COPY --from=build /rails /rails # Run and own only the runtime files as a non-root user for security RUN groupadd --system --gid 1000 rails && \ useradd rails --uid 1000 --gid 1000 --create-home --shell /bin/bash && \ chown -R rails:rails db log storage tmp USER 1000:1000 # Entrypoint prepares the database. ENTRYPOINT ["/rails/bin/docker-entrypoint"] # Start the server by default, this can be overwritten at runtime EXPOSE 3000 CMD ["./bin/rails", "server"]