# syntax = docker/dockerfile:1 FROM ruby:slim as build RUN apt-get update &&\ apt-get install --yes build-essential git RUN gem install rails RUN rails new demo --minimal --skip-active-record FROM ruby:slim COPY --from=build /demo /demo COPY --from=build /usr/local/bundle /usr/local/bundle COPY <<-"EOF" /demo/config/routes.rb Rails.application.routes.draw { root "rails/welcome#index" } EOF WORKDIR demo ENV RAILS_ENV=production EXPOSE 3000 CMD bin/rails server