Dockerfile
FROM ruby:2.3.0-alpine
RUN apk add --update --no-cache \
build-base \
nodejs \
tzdata \
libxml2-dev \
libxslt-dev \
postgresql-dev
RUN bundle config build.nokogiri --use-system-libraries
ENV APP_HOME /usr/src/app
RUN mkdir -p $APP_HOME
WORKDIR $APP_HOME
EXPOSE 3000
ENV BUNDLE_PATH /ruby_gems
CMD ["bin/rails", "s", "-b", "0.0.0.0"]