index.js

var request = require('request');
var fs    = require('fs');

var url = process.argv[2];       // url of the site
var certFile = process.argv[3];  // certificate from server

var ca =  fs.readFileSync(certFile, 'ascii');
var options = {
    url: url,
    // rejectUnauthorized: false,
    ca: ca
};

var test = request.get(options, function (error, response, body) {
  if (error) {
    console.log('Error');
    console.log(JSON.stringify(error, null, 4));
  } else {
    delete response['body'];
    console.log(JSON.stringify(response, null, 4)) // Show the HTML for the Google homepage.
  }
});

// NODE 4.4.7 (Ubuntu 16.04 LTS)
// Error
// {
//     "code": "UNABLE_TO_GET_ISSUER_CERT"
// }


// NODE 6.0.0 (Ubuntu 16.04 LTS)
// {
//     "statusCode": 200,
//     ...