nightwatch.conf.js

const SCREENSHOT_PATH = './screenshots/';
const BINPATH = './node_modules/nightwatch/bin/';

// we use a nightwatch.conf.js file so we can include comments and helper functions
module.exports = {
  'src_folders': [
    'nightwatch/tests'     // we use '/test' as the name of our test directory by default. So 'test/e2e' for 'e2e'.
  ],
  'custom_commands_path': './nightwatch/commands',
  'custom_assertions_path': './nightwatch/assertions',
  'output_folder': false,
  'selenium': { // downloaded by selenium-download module (see readme)
    'start_process': true, // tells nightwatch to start/stop the selenium process
    'server_path': './node_modules/nightwatch/bin/selenium.jar',
    'host': '127.0.0.1',
    'port': 4444, // standard selenium port
    'cli_args': { // chromedriver is downloaded by selenium-download (see readme)
      'webdriver.chrome.driver' : './node_modules/nightwatch/bin/chromedriver'
    }
  },
  'test_settings': {
    'default': {
      'screenshots': {
        'enabled': true, // if you want to keep screenshots
        'path': './screenshots' // save screenshots here
      },
      'globals': {
        'waitForConditionTimeout': 5000 // sometimes internet is slow so wait.
      },
      'desiredCapabilities': { // use Chrome as the default browser for tests
        'browserName': 'chrome'
      }
    },
    'chrome': {
      'desiredCapabilities': {
        'browserName': 'chrome',
        'javascriptEnabled': true // turn off to test progressive enhancement
      }
    }
  }
}
/**
 * selenium-download does exactly what it's name suggests;
 * downloads (or updates) the version of Selenium (& chromedriver)
 * on your localhost where it will be used by Nightwatch.
 /the following code checks for the existence of `selenium.jar` before trying to run our tests.
 */

require('fs').stat(BINPATH + 'selenium.jar', function (err, stat) { // got it?
  if (err || !stat || stat.size < 1) {
    require('selenium-download').ensure(BINPATH, function(error) {
      if (error) throw new Error(error); // no point continuing so exit!
      console.log('✔ Selenium & Chromedriver downloaded to:', BINPATH);
    });
  }
});

function padLeft (count) { // theregister.co.uk/2016/03/23/npm_left_pad_chaos/
  return count < 10 ? '0' + count : count.toString();
}

var FILECOUNT = 0; // "global" screenshot file count
/**
 * The default is to save screenshots to the root of your project even though
 * there is a screenshots path in the config object above! ... so we need a
 * function that returns the correct path for storing our screenshots.
 * While we're at it, we are adding some meta-data to the filename, specifically
 * the Platform/Browser where the test was run and the test (file) name.
 */
function imgpath (browser) {
  var a = browser.options.desiredCapabilities;
  var meta = [a.platform];
  meta.push(a.browserName ? a.browserName : 'any');
  meta.push(a.version ? a.version : 'any');
  meta.push(a.name); // this is the test filename so always exists.
  var metadata = meta.join('~').toLowerCase().replace(/ /g, '');
  return SCREENSHOT_PATH + metadata + '_' + padLeft(FILECOUNT++) + '_';
}

module.exports.imgpath = imgpath;
module.exports.SCREENSHOT_PATH = SCREENSHOT_PATH;