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@matiasmasca
Created June 17, 2025 19:57
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Ruby on Rails 7.2.1 on Docker - Default files
#!/bin/bash -e
# Enable jemalloc for reduced memory usage and latency.
if [ -z "${LD_PRELOAD+x}" ] && [ -f /usr/lib/*/libjemalloc.so.2 ]; then
export LD_PRELOAD="$(echo /usr/lib/*/libjemalloc.so.2)"
fi
# If running the rails server then create or migrate existing database
if [ "${1}" == "./bin/rails" ] && [ "${2}" == "server" ]; then
./bin/rails db:prepare
fi
exec "${@}"
# Move this file to <your-rails-app-code./bin/
# syntax = docker/dockerfile:1
# This Dockerfile is designed for production, not development. Use with Kamal or build'n'run by hand:
# docker build -t my-app .
# docker run -d -p 80:80 -p 443:443 --name my-app -e RAILS_MASTER_KEY=<value from config/master.key> my-app
# Make sure RUBY_VERSION matches the Ruby version in .ruby-version
ARG RUBY_VERSION=3.3.2
FROM docker.io/library/ruby:$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
RUN apt-get update -qq && \
apt-get install --no-install-recommends -y build-essential git 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/
# Precompiling assets for production without requiring secret RAILS_MASTER_KEY
RUN SECRET_KEY_BASE_DUMMY=1 ./bin/rails assets:precompile
# 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"]
# See https://docs.docker.com/engine/reference/builder/#dockerignore-file for more about ignoring files.
# Ignore git directory.
/.git/
/.gitignore
# Ignore bundler config.
/.bundle
# Ignore all environment files (except templates).
/.env*
!/.env*.erb
# Ignore all default key files.
/config/master.key
/config/credentials/*.key
# Ignore all logfiles and tempfiles.
/log/*
/tmp/*
!/log/.keep
!/tmp/.keep
# Ignore pidfiles, but keep the directory.
/tmp/pids/*
!/tmp/pids/.keep
# Ignore storage (uploaded files in development and any SQLite databases).
/storage/*
!/storage/.keep
/tmp/storage/*
!/tmp/storage/.keep
# Ignore assets.
/node_modules/
/app/assets/builds/*
!/app/assets/builds/.keep
/public/assets
# Ignore CI service files.
/.github
# Ignore development files
/.devcontainer
# Ignore Docker-related files
/.dockerignore
/Dockerfile*
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