launch-darkly-demo-app.js

var LaunchDarkly = require('ldclient-node');

const SDK_KEY = 'Add your SDK KEY here';
const FEATRUE_KEY = 'show-new-navbar';

const ldclient = LaunchDarkly.init(SDK_KEY);
const user1 = {"key": "user-one"};
const user2 = {"key": "user-two"};

const checkFeature = function(user) {
  console.log(`Checking feature "${FEATRUE_KEY}" for user key "${user.key}"`)
    ldclient.variation(FEATRUE_KEY, user, false,
     function(err, showFeature) {
        if (showFeature) {
          console.log('Yeah! showFeature is', showFeature);
        } else {
          console.log('Nop! showFeature is', showFeature);
        }
     });
};

const start = () => {
  ldclient.once('ready', function() {
    checkFeature(user1);
    checkFeature(user2);
  });
};

start();