$ docker run -v /run/docker.sock:/run/docker.sock centurylink/dockerfile-from-image
Usage: dockerfile-from-image.rb [options] <image_id>
-f, --full-tree Generate Dockerfile for all parent layers
-h, --help Show this message
$ docker run -v /run/docker.sock:/run/docker.sock centurylink/dockerfile-from-image ruby
FROM buildpack-deps:latest
RUN useradd -g users user
RUN apt-get update && apt-get install -y bison procps
RUN apt-get update && apt-get install -y ruby
ADD dir:03090a5fdc5feb8b4f1d6a69214c37b5f6d653f5185cddb6bf7fd71e6ded561c in /usr/src/ruby
RUN chown -R user:users .
RUN autoconf && ./configure --disable-install-doc
RUN apt-get purge -y ruby
RUN echo 'gem: --no-rdoc --no-ri' >> /.gemrc
ONBUILD ADD . /usr/src/app
ONBUILD WORKDIR /usr/src/app
ONBUILD RUN [ ! -e Gemfile ] || bundle install --system