Install latest node.js and yarn on Ubuntu

yarn.sh

#!/bin/bash

ND_VERSION=8.12.0
ND_FILE=node-v$ND_VERSION-linux-x64.tar.gz

function download {
    wget https://nodejs.org/dist/v$ND_VERSION/$ND_FILE && sudo tar -C /usr/local --strip-components 1 -xzf $ND_FILE && rm $ND_FILE
}

PS3='Please choose platform: '
options=("Ubuntu/Debian" "CentOS" "ARMv6" "Quit")
select opt in "${options[@]}"
do
    case $opt in
        "Ubuntu/Debian")
            download
            sudo curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | apt-key add -
            sudo echo "deb https://dl.yarnpkg.com/debian/ stable main" | tee /etc/apt/sources.list.d/yarn.list
            sudo apt update
            sudo apt install --no-install-recommends yarn -y
            break
            ;;
        "CentOS")
            yum install wget -y &&
            download &&
            sudo curl --silent --location https://dl.yarnpkg.com/rpm/yarn.repo | tee /etc/yum.repos.d/yarn.repo &&
            sudo curl --silent --location https://rpm.nodesource.com/setup_6.x | bash - &&
            sudo yum install yarn -y
            break
            ;;
        "ARMv6")
            ND_FILE=node-v$ND_VERSION-linux-armv6l.tar.gz
            download
            sudo curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | apt-key add -
            sudo echo "deb https://dl.yarnpkg.com/debian/ stable main" | tee /etc/apt/sources.list.d/yarn.list
            sudo apt update
            sudo apt install --no-install-recommends yarn -y
            break
            ;;
        "ARMv7")
            ND_FILE=node-v$ND_VERSION-linux-armv7l.tar.gz
            download
            sudo curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | apt-key add -
            sudo echo "deb https://dl.yarnpkg.com/debian/ stable main" | tee /etc/apt/sources.list.d/yarn.list
            sudo apt update
            sudo apt install --no-install-recommends yarn -y
            break
            ;;
        "Quit")
            break
            ;;
        *) echo Invalid option;;
    esac
done