Use npm with a proxy that requires authentication

It’s pretty easy to configure npm to connect through a proxy by setting the proxy and https-proxy config settings and you can even use npm config set which will store them in your .npmrc file. Connecting through a corporate proxy that requires authentication, however, can be a little trickier.

To specify your credentials, you have to place them in the proxy url so your npm command would look something like this:

npm install --proxy http://user_name:password@proxy.company.com:8080

Typing that every time will get old fast. Again you can use npm config set but the security conscious will probably feel a bit uneasy having your credentials sitting in plain text in a file on disk especially if, like most corporate environments, the proxy uses your active directory credentials.

To ease the pain I created a powershell wrapper function around npm to prompt for your proxy password:

function np {
  $response = Read-host "Enter password" -AsSecureString
  $password = [Runtime.InteropServices.Marshal]::PtrToStringAuto([Runtime.InteropServices.Marshal]::SecureStringToBSTR($response))
  $un = [Environment]::Username
  $proxy = "http://${un}:${password}@proxy.company.com/"
  npm $args --proxy $proxy
}

If you add this to your powershell profile then you can then you can call np in place of npm and it will prompt you to type your password and then call npm with the parameters you supplied along with the proxy url.

This does assume the proxy username is the same as your machine username but if not you could tweak the script to prompt you for both.