Ruby (2.4.1), node with phantomjs bundled in.
Dockerfile will create an images for docker containers
with ruby, nodejs and phantomjs. Mainly to run the headless tests of karma.
The reason that phantomjs is contained in a git repository is because
of the time (> 1.5h) it takes to build phantomjs from source on my macbook.
To avoid this time, a separate Dockerfile is used to build the binary.
Getting the image
$ docker pull prograils/ruby-node-phantomjs
$ docker run -t -i prograils/ruby-node-phantomjs
$ bundle exec rspec