It looks having installed the nodejs solved the problem.
Just google for how to install node.js and it shall be a breath.
if you are on debian destro
sudo apt get install nodejs
Shall do the trick.
gem install json -v ‘1.8.1’ error on rails installing fedora
This is a dependency issue on rails
First install
yum -y install ruby-devel rubygems
Then install
gem install json -v '1.8.1'