sudo curl -sL https://deb.nodesource.com/setup_6.x | sudo -E bash -

## Adding the NodeSource signing key to your keyring...

+ curl -s https://deb.nodesource.com/gpgkey/nodesource.gpg.key | apt-key add -
E: gnupg, gnupg2 and gnupg1 do not seem to be installed, but one of them is required for this operation
(23) Failed writing body
Error executing command, exiting