Nightwatch.js script for taking screenshots of a given URL at various browser widths.

viewport-shots.js

/*
* Takes provided URL passed as argument and make full height screenshots of this page 
* with several viewport widths using Nightwatch.js with Selenium.
*
* These viewport widths are taken from common android and iOS devices. Modify as needed.
*
* Takes an optional second argument for the path where screenshots are saved.
*
* Usage:
* $ nightwatch -t viewport-shots.js http://example.com
* $ nightwatch -t viewport-shots.js http://example.com directory/to/save
*/


module.exports = {
  "Viewport Screenshots" : function (browser) {
    // Make sure a URL has been passed
    if (process.argv.length < 5) {
      console.log('No URL was specified');
      browser.end();
    }

    var url = process.argv[4],
        save_directory = 'screenshots',
        viewport_widths = [240, 320, 360, 568, 603, 640, 768, 800, 960, 1024, 1280, 1400, 1600, 1920];
    
    // Optional argument - path to save
    if (process.argv.length >= 6) {
      save_directory = process.argv[5];
    }

    browser.url(url).waitForElementVisible('body', 1000);
      
    viewport_widths.forEach(function(width){
      browser
        .resizeWindow(width, 300)
        .saveScreenshot(save_directory + '/' + width + '.png')
    });
      
    browser.end();
  }
};

Can these screenshots be accessed in a Travis build?