usingcaccerts.js

var https = require('https');
var fs = require('fs');
var options = {
  hostname: 'encrypted.google.com',
  port: 443,
  path: '/',
  method: 'GET',
  ca: [fs.readFileSync('/yourapp/certs/intCA1Cert.pem'), fs.readFileSync('/yourapp/certs/ rootCACert.pem')],
  rejectUnauthorized: true
};
options.agent = new https.Agent(options);
var req = https.request(options, function(res) {
  ...
}