railties/lib/rails/generators/rails/app/templates/Dockerfile.tt

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# syntax = docker/dockerfile:1

# Note: This Dockerfile is optimized for production deployment and isn't a good base
# for development enviroments.

# Make sure RUBY_VERSION matches the Ruby version in .ruby-version
ARG RUBY_VERSION=<%= gem_ruby_version %>
FROM registry.docker.com/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 <%= dockerfile_base_packages.join(" ") %>

# 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<%= using_node? ? " and node modules" : "" %>
RUN apt-get install --no-install-recommends -y <%= dockerfile_build_packages.join(" ") %>

<% if using_node? -%>
# Install JavaScript dependencies
ARG NODE_VERSION=<%= node_version %>
ARG YARN_VERSION=<%= dockerfile_yarn_version %>
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

<% end -%>
<% if using_bun? -%>
ENV BUN_INSTALL=/usr/local/bun
ENV PATH=/usr/local/bun/bin:$PATH
ARG BUN_VERSION=<%= dockerfile_bun_version %>
RUN curl -fsSL https://bun.sh/install | bash -s -- "bun-v${BUN_VERSION}"

<% end -%>
# Install application gems
COPY Gemfile Gemfile.lock ./
RUN bundle install && \
    rm -rf ~/.bundle/ "${BUNDLE_PATH}"/ruby/*/cache "${BUNDLE_PATH}"/ruby/*/bundler/gems/*/.git<% if depend_on_bootsnap? -%> && \
    bundle exec bootsnap precompile --gemfile<% end %>

<% if using_node? -%>
# Install node modules
COPY package.json yarn.lock ./
RUN yarn install --frozen-lockfile

<% end -%>
<% if using_bun? -%>
# Install node modules
COPY package.json bun.lockb ./
RUN bun install --frozen-lockfile

<% end -%>
# Copy application code
COPY . .

<% if depend_on_bootsnap? -%>
# Precompile bootsnap code for faster boot times
RUN bundle exec bootsnap precompile app/ lib/

<% end -%>
<% unless dockerfile_binfile_fixups.empty? -%>
# Adjust binfiles to be executable on Linux
<%= "RUN " + dockerfile_binfile_fixups.join(" && \\\n    ") %>

<% end -%>
<% unless options.api? || skip_asset_pipeline? -%>
# Precompiling assets for production without requiring secret RAILS_MASTER_KEY
RUN SECRET_KEY_BASE_DUMMY=1 ./bin/rails assets:precompile

<% end -%>

<% if using_node? -%>
RUN rm -rf node_modules
<% end %>

# Final stage for app image
FROM base

# Clean up installation packages to reduce image size
RUN rm -rf /var/lib/apt/lists /var/cache/apt/archives

# 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 <%= dockerfile_chown_directories.join(" ") %>
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"]