NPM preinstall for private registries behind VPNs

package.json

{
  "name": "myApp",
  "version": "1.0.0",
  "scripts": {
  	"preinstall": "sh vpn-check.sh"
  },
  "dependencies": {
    "moduleOnPrivateRepo": "1.0.0"
  }
}

vpn-check.sh

#!/bin/bash

# Because you need to be on the VPN to connect to the private NPM Registry,
# this script checks for that before running `npm install`.
# This helps prevent developer confusion when they're not connected to the VPN
# and `npm install` hangs when trying to find the registry server
# If the ping fails, NPM quits the install and hopefully the dev reads the error message

echo 'Checking if you are connected to the VPN'

ping -c 1 -W 10 your.ip.address.here &> /dev/null

if [ $? -ne 0 ]
then
    echo '\n-----\nERROR: You need to be connected to the VPN to run npm install.\n-----'
    exit 1
else
	echo 'You are connected. Continuing with install.'
fi