Dockerfile

# Make sure RUBY_VERSION matches the Ruby version in .ruby-version
ARG RUBY_VERSION=3.4.1
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 postgresql-client && \
    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:test"

# Throw-away build stage to reduce size of final image
FROM base AS build

# Install packages needed to build gems
RUN apt-get update -qq && \
    apt-get install --no-install-recommends -y build-essential git libpq-dev pkg-config && \
    rm -rf /var/lib/apt/lists /var/cache/apt/archives

# 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

# Copy application code
COPY . .

# Precompile bootsnap code for faster boot times
RUN bundle exec bootsnap precompile app/ lib/

# Set dummy secret key for asset compilation
ENV SECRET_KEY_BASE_DUMMY=1

# Create necessary directories with proper permissions
RUN mkdir -p public/assets app/assets/builds tmp/cache && \
    chmod -R 755 public app/assets tmp

# Build TailwindCSS first
RUN bundle exec rails tailwindcss:build

# Precompile assets
RUN bundle exec rails assets:precompile

# Verify assets were created
RUN ls -la public/assets/ && echo "✅ Assets compiled successfully"

# Final stage for app image
FROM base AS production

# Create rails user and group first
RUN groupadd --system --gid 1000 rails && \
    useradd rails --uid 1000 --gid 1000 --create-home --shell /bin/bash

# Copy built artifacts: gems, application
COPY --from=build "${BUNDLE_PATH}" "${BUNDLE_PATH}"
COPY --from=build /rails /rails

# Verify assets were copied to production stage
RUN ls -la /rails/public/assets/ && echo "✅ Assets present in production image"

# Set proper ownership for all necessary directories
RUN chown -R rails:rails /rails && \
    mkdir -p /rails/tmp/pids /rails/log /rails/storage && \
    chown -R rails:rails /rails/tmp /rails/log /rails/storage /rails/public

# Switch to rails user
USER 1000:1000

# Entrypoint prepares the database.
ENTRYPOINT ["/rails/bin/docker-entrypoint"]

# Start server via Thruster by default, this can be overwritten at runtime
EXPOSE 80
CMD ["./bin/thrust", "./bin/rails", "server"]