Ruby's Bundler Dockerfile

Dockerfile

# This Dockerfile is aimed at building it from a directory containing a Gemfile.
# It installs the Gemfile packages and then gives you the "bundle exec" entry point.
#
# Usage:
#  * docker build --tag=bundle-exec .
#  * docker run -it --rm --user $(id -u):$(id -g) -v $(pwd):/src bundle-exec
# Example: docker run -it --rm --user $(id -u):$(id -g) -v $(pwd):/src bundle-exec compass compile -e production

FROM ubuntu:16.04

RUN apt-get update && apt-get install -y bundler

# Buildtime
COPY Gemfile /tmp/Gemfile
RUN ["bundle", "install", "--gemfile=/tmp/Gemfile"]

# Runtime
VOLUME /src
WORKDIR /src
ENTRYPOINT ["bundle", "exec"]