chromedriver

chromedriver.js

var chromedriver = require('chromedriver');
var moduleFolder = '../../node_modules/chromedriver/lib/chromedriver/';
var path = require('path');
var binPath = path.resolve(path.join(moduleFolder, process.platform === 'win32' ? 'chromedriver.exe' : 'chromedriver'));

module.exports = {
  defaultInstance : null,

  start : function() {
    this.defaultInstance = require('child_process').execFile(binPath, [
      '--url-base=/wd/hub'
    ]);
    return this.defaultInstance;
  },

  stop : function () {
    if (this.defaultInstance != null){
      this.defaultInstance.kill();
    }
  }
};

globals.js

var chromedriver = require('./chromedriver.js');
module.exports = {
  before: function (done) {
    chromedriver.start();
    done();
  },
  
  after : function(done) {
    chromedriver.stop();
    done();
  }
};

nightwatch.json

  {  
    "chrome" : {
      "selenium" : {
        "start_process" : false
      },
      "selenium_port" : 9515,
      "desiredCapabilities": {
        "browserName": "chrome"
      }
    }
  }