Sanity.js is a small library that checks a list of environment variables are set and meet your format requirements before your app starts up.
Here's a quick snippet of how it could be used:
var sanity = require('sanity'); sanity.check(['USER', 'MACHTYPE', 'INVISIBLE_FRIENDS', 'AREA_51']); // Output if INVISIBLE_FRIENDS and AREA_51 are undefined ERROR: Required settings are not correct! INVISIBLE_FRIENDS: undefined AREA_51: undefined
Full documentation (and tests!) are a the sanity repo.