Create basic ruby-alpine image

AS a developer
I WANT TO have basic ruby-alpine imageA
SO THAT building is faster

Dockerfile should be like

FROM alpine:3.18.2

ENV RAILS_ENV=development

RUN apk --update --no-cache add gnupg curl bash \
    gcc ruby procps musl-dev make linux-headers zlib zlib-dev openssl openssl-dev ruby-dev yaml-dev


RUN gem install rake -N
RUN gem install bundle

RUN apk --update --no-cache add npm nodejs g++ sqlite-dev
RUN apk --update --no-cache add gcompat

and the rest should be

FROM skocic/ruby-alpine

RUN addgroup $GROUP && \
    adduser -h /home/$USER -g 'RVM User' -s /bin/bash -G $GROUP -D $USER

ENV USER    rvm
ENV GROUP   rvm
USER rvm

RUN gpg2 --keyserver keyserver.ubuntu.com --recv-keys 409B6B1796C275462A1703113804BB82D39DC0E3 7D2BAF1CF37B13E2069D6956105BD0E739499BDB
RUN curl -sSL https://get.rvm.io | bash -s stable
SHELL ["/bin/bash", "-cl"]
RUN echo "rvm_gems_path=~/.rvm" > ~/.rvmrc

COPY .ruby-version .

RUN gem install nokogiri sqlite3 sassc tzinfo-data

RUN source ~/.rvm/scripts/rvm \
 && rvm install ruby-$(cat .ruby-version) --autolibs=0 --movable --disable-binary \
 && rvm use ruby-$(cat .ruby-version) --default
#RUN /usr/local/rvm/bin/rvm alias create default ruby-$(cat .ruby-version)

WORKDIR /app

COPY --chown=$GROUP:$USER Gemfile Gemfile.lock ./
RUN bundle config set --local deployment true  # Install dependencies into ./vendor/ruby
RUN bundle install -j $(nproc)

COPY --chown=$GROUP:$USER . .

ENTRYPOINT ["/bin/bash", "-cl", "$0 $@"]

EXPOSE 3000