Headless Javascript Testing


6 Popular Headless Browsers for Web Testing - KeyCDN

6 Popular Headless Browsers for Web Testing – KeyCDN

By Cody ArsenaultPublished on February 22, 2018
How do you know if the user interface (UI) of a website you’re developing works as it should and the site as a whole delivers the optimal user experience (UX)? Headless browsers give you a fast, lightweight way to automate high-level actions and get an idea of how well your site operates in common headless options are available, including headless versions of popular browsers like Chrome and Firefox and tools to simulate several different browsers. Familiarize yourself with the benefits of headless testing, and learn more about the possibilities available so that you can select the best browsers to use for web development and of headless browsersHeadless browsing may seem like an odd term, but it’s simply a name for a browser or browser simulation without the recognizable graphical interface. Instead of testing a site or performing common actions using familiar graphical elements, use cases are automated and tested with a command-line interface. Headless browsers are commonly used for:Website and application testingJavaScript library testingJavaScript simulation and interactionsRunning one or more automated UI tests in the backgroundThese actions help developers confirm whether or not common website activities flow smoothly and can identify potential problems with UI and UX. Since the experience of the end user is paramount in today’s highly personalized web environment, it’s crucial to work out as many bugs as possible before launching the public version of a use cases for headless testingWhat use cases should you test with headless browsers? Consider the most frequent actions users may take on any given page. Each point at which a user types, clicks or otherwise interacts with on-page elements is a point at which something could go wrong, and you’re better off finding out about and fixing problems in the testing stage than discovering glitches weeks or even months later when complaints come pouring a headless testing environment, you can write and execute scripts to:Test basic and alternative flowsSimulate clicks on links and buttonsAutomate form filling and submissionTest SSL performanceExperiment with various server loadsGet reports on page response timesScrape useful website codeTake screenshots of resultsTesting these use cases provides you with a solid overview of how a site’s UI performs and gives you essential information for making changes before oosing a headless browserToday’s websites present a number of complex use cases developers didn’t have to think about in the past. An increased focus on engagement creates more elements with which users can interact, and ecommerce sites, in particular, can require complex multi-level flows for proper navigation. Any problem impeding a smooth experience for users can undermine the success of the this in mind as you evaluate popular headless browsers. You want a lightweight solution with very little draw on resources so that you can run it in the background without slowing down development work, but the same solution must allow you to execute every test necessary to simulate the expected actions of target all headless browsers are suited for the same testing scenarios, so you may have to try several different options to find the right combination of tools for your development needs. Take a look at these six popular choices for web developers. 1. Firefox headless modeWith the launch of version 56 of Firefox, Mozilla began offering support for headless testing. Instead of using other tools to simulate browser environments, developers can now connect several different APIs to run Firefox in headless mode and test a variety of use cases. Headless Firefox may be driven by:SeleniumSlimmerJSW3C WebDriverMany developers appear to prefer Selenium as an API for headless Firefox testing and automation, but you can use the option with which you’re most comfortable with for scripting and running basic unit all the potential interactions a user can have on a modern website, using Firefox headless to drill down to individual elements is a helpful part of the development process. Whereas a user may encounter a problem as part of a complex flow and become frustrated trying to identify and report what went wrong, you can use Firefox in headless mode to work out the kinks of each individual interaction in a flow. 2. Headless ChromeDevelopers familiar with Chrome can launch version 59 or later in headless mode to utilize all the possibilities afforded by Chromium and the Blink rendering engine. This lightweight, memory-sparing headless browser gives you the tools to:Test multiple levels of navigationGather page informationTake screenshotsCreate PDFsNavigation is an especially important part of modern website environments and is becoming even more critical with the continued increase in mobile users. Try headless Chrome when you want to make sure users can move easily throughout a site. Collect reports and images of how the site responds, and use this information to make changes to improve the UI. 3. PhantomJSComplexity is commonplace in the modern internet landscape, and PhantomJS is built to handle it all using basic command line testing. This headless WebKit is scriptable via the JavaScript API and uses CasperJS to handle testing. Capable of simulating full navigation scenarios, PhantomJS can reveal all the places where a user may encounter errors while pport for multiple web standards makes PhantomJS flexible and highly capable. Page automation, network monitoring, and other important features allow you to simulate everything from the most basic user interactions to flows containing multiple inputs. Use this headless option for:Testing navigationSimulating user behaviorWorking with assertionsTaking screenshotsAnother benefit of PhantomJS is its open source status. The program was released in 2011 and is still being updated by dedicated developers. Check out the official GitHub repo. 4. is another lightweight framework used to test client side JavaScript in a simulated environment without a browser. The current version of Zombie (Zombie 5. x) is tested to work with versions 4-6. A few benefits of include:Runs on making it easy to integrate with your projectFully featured APIInsanely fastZombie JS also provides a set of assertions that you can access directly from the browser object. For example, an assertion can be used to check if a page loaded successfully. Apart from assertions, Zombie JS offers methods to handle cookies, tabs, authentication, and more. 5. HtmlUnitWritten in Java, HtmlUnit allows you to use Java code to automate many of the basic ways in which users interact with websites. Use it to test:Filling in and submitting formsClicking linksSite redirectsHTTP authenticationHTTPS page performanceHTTP header performanceThe tool’s ability to simulate several different browsers expands its functionality even more. Using HtmlUnit, you can create scripted use cases in Chrome, Firefox 38 and later, Edge, and IE8 and IE11. This covers a significant number of new and legacy browsers, helping to ensure every user has a superior experience once a site goes ommerce sites rely heavily on most of the elements HtmlUnit allows you to test. Form submission, site security, and navigation are all integral parts of the ecommerce UI and have a significant impact on conversions and sales. Poor UI means poor UX, and customers in a fast-paced online world abandon such sites to shop with the competition instead. HtmlUnit is a helpful ally when you’re working to craft a business site with superior performance. 6. SplashIn the documentation for Splash, the headless browser is hailed as being lightweight and offering a variety of features to developers. This “JavaScript rendering service” operates with an HTTP API, implemented in Python 3 using Twisted and may be the best go-to tool if your use cases require:Understanding HTML performanceTesting rendering and load speedsTurning off images or using AdBlock for faster loadingVisualizing website UXUsing Lua browsing scriptsProcessing more than one page at a timeSplash provides rendering information in the HAR format and also allows you to take screenshots of results. This headless browser may also be integrated with Scrapy in scenarios where you need or want to scrape code from other websites. Thanks to its versatility, Splash is a useful tool for developers seeking a “jack of all trades” for their testing mmaryThese browsers represent just a few of the testing environments available to developers. That being said, by taking the first 5 headless browsers mentioned in this post and comparing them with Google Trends, it’s obvious that PhantomJS is still one of the most popular headless browser there is a variety to choose from, you can try out more than one for different use cases and determine which works best to test particular scenarios. From simple interactions to fully automated flows, headless browsers provide the framework you need to optimize UI and UX in each site you develop.
Why Should I Run My Selenium Tests in Headless? - SmartBear

Why Should I Run My Selenium Tests in Headless? – SmartBear

Headless testing is greatly underutilized – here are three quick ways it can increase performance
Selenium has grown to be one of the most popular automation tools available today. It automates many tasks needed for online testing, including checking titles, navigating pages, clicking links, and much more. Many developers already use the full set of capabilities Selenium offers, but few know about running their tests in headless browsers. And even fewer actually deploy this approach in their daily testing. With headless testing you can increase your testing performance to an all-time high.
What is Headless testing?
Headless testing is simply running your Selenium tests using a headless browser. It operates as your typical browser would, but without a user interface, making it excellent for automated testing.
How does Headless testing benefit developers?
There are several benefits, actually. They can create new testing opportunities, as well as accelerate tests you’re already running.
Benefits include:
Greater testing reach
Improved speed and performance
When running Selenium tests, you typically need a machine that supports the graphics of the web browser that you’re testing on. With headless testing we get rid of this need and open up a whole new set of devices to test on. Ex. Servers, docker containers, etc.
Selenium tests can take a while to complete, due to elements on a page that the browser needs to load. Headless testing gets rid of this load time, allowing you to cut your testing times significantly. In our tests with headless testing, we’ve seen a 30% reduction of test execution times. And you can use other techniques, like running more tests in parallel, to amplify that benefit.
Running normal Selenium tests take up your screen time, keeping you from being able to accomplish anything else on that device. With the UI disabled, headless testing lets you continue to use your computer while the tests execute in the background.
In our conversations with customers, we’ve found that headless testing has let developers experience all of these benefits – and many more!
How have you used headless testing to improve your processes? And where do you see opportunities to take advantage of them? Respond in the comments!
To help you get started Headless testing with CrossBrowserTesting, visit our help page: Headless Testing Documentation
Headless Browser Testing Awesomeness Pros and Cons

Headless Browser Testing Awesomeness Pros and Cons

WHAT IS HEADLESS TESTING? So what is this headless testing “browsing”? It actually is what it sounds like. Headless testing is when you run a UI-based browser test without showing the browser UI. It’s running a test or running a script against a browser but without the browser, UI starting up. Why would you want to use headless browsers? There are a lot of pros and cons to following this approach. Using a headless browser might not be very helpful for browsing the Web, but for automating tasks and tests it’s awesome. Why Should You Care About Testing with a Headless Browser? Follow the money is such a cliché, but it’s a key indicator of what I think is a real trend and something I should pay attention to. For example, Sauce Labs just came out with a new service called Sauce Headless, a cloud-based headless testing solution. I know the folks at Sauce are smart folks. They don’t develop anything unless they’ve gotten feedback from their users that it’s needed functionality. I’m sure they will not be alone with their focus on headless testing. Headless browser testing is a shift-left design thinking that is important for software QA. This means the tests are automated and run in the browser without the need for any user interaction. As we shift more and more left in our software development lifecycle, we need to give feedback to our developers faster and faster. One way to do this is using some quick checks leveraging a headless browser. Automation in Software Production If you know me at all, you also know that I’m very automation inclusive. To me, it’s not just about automation testing. It’s anything that you can automate to save someone time or effort in any part of the software delivery lifecycle–whether it’s developing, quality, testing, DevOps, or installation; I would refer to any of these as automation. And headless browsers are something you can actually utilize for a lot of these efforts. Headless browser testing is the process of testing an application or website without a human user watching. This technique has pros and cons that will depend on your particular project. PRO: Headless Browsers are Faster than Real Browsers One definite “pro” of headless browsers is that they are typically faster than real browsers; the reason being that since you aren’t starting up a browser GUI you can bypass all the time a real browser takes to load CSS, JavaScript and open and render HTML. I have to admit although, that it’s not exactly like night and day. But you will typically see a 2x to 15x faster performance when using a headless browser. So if performance is critical for you, headless browsers may be a way to go. Headless Browser Scraping Another advantage of headless browsers is that they can be used to scrape websites. To do this, you don’t necessarily want to have to manually start up a website, however. You can go to it headlessly and just scrape the HTML. You don’t need to render a full browser to do that. For example, say your job needs some data sports statistics, or to compare prices between different sites. Since it’s just data you’re looking for, it doesn’t make sense to start up a full instance of a browser; it’s just extra overhead–and sometimes the less overhead you have, the quicker you’ll get results back. It may not necessarily be a test, and that’s okay. Again, you want to leverage the right tools to do the right things. I also think that headless browser scraping is not leveraged by many testers – and that’s a shame. So if you want to do some website scraping to help you with a test, later on, you won’t necessarily need the overhead of starting a full-blown browser; you can utilize headless browsers to obtain that functionality for you. Save Your Developers Time I’m aware that a lot of developers use a headless browser for unit testing code changes for their websites and mobile apps. Being able to do all this from a command line without having to manually refresh or start a browser saves them lots and effort. For example, Rob Friesel, author of the PhantomJS CookBook in a TestTalks interview explained how his developers use the headless browser PhantomJS: “Although PhantomJs in itself is not a test framework, it’s a really good canary in a coal mine to give you some confidence; if your tests are passing, you can have a high degree of confidence that your code is ok. ” Monitor Performance With Headless Browser Scripts Another common use is to use a headless browser script to monitor network application performance. Some even use it to automate the rendering and screen capturing of their website images to perform layout checks in an automated fashion. I think these are some of the reasons why Google has also developed a new headless Chrome API called Puppeteer that was designed to handle many of these developer use cases. Headless Browser Testing Ideas Besides the one we’ve already covered, here are some other uses for headless browsers that I’ve run across: Run tests on a machine without a display Setup Data Testing SSL Simulating multiple browsers on a single machine Running tests on a headless system like Linux OS without GUI Retrieve and render PDFs Layout testing – since headless browsers render and interpret CSS & HTML like a real browser you can use it to test style elements. Examples of When You Might NOT Want to Use a Headless Browser Of course, there are a number of reasons why you may wish to use a real browser as opposed to a headless browser. For instance: You need to mimic real users You need to visually see the test run If you need to do lots of debugging, headless debugging can be difficult. Popular Headless Browsers Google Puppeteer- The Headless Browser Puppeteer is a Node library. It gives you a high-level API to control headless Chrome or Chromium over the DevTools Protocol. It also can also be tweaked to use full (non-headless) Chrome or Chromium. Google Chrome since version 59 Firefox versions 55 & 56 PhantomJS –is a headless WebKit scriptable with a JavaScript API. It has fast and native support for various web standards: DOM handling, CSS selector, JSON, Canvas, and SVG. *This is no longer being maintained. Because of this, you might want to avoid. HtmlUnit –is a “GUI-Less browser for Java programs”. It models HTML documents and provides an API that allows you to invoke pages, fill out forms, click links, etc… just like you do in your “normal” browser. Splinter – Splinter is a headless browser Python-centric option. It’s open sourced and is used for testing web applications using Python. For example, you can use it to automate browser actions, such as visiting URLs and interacting with their items. jBrowserDriver – A programmable, embeddable web browser driver compatible with the Selenium WebDriver spec — headless, WebKit-based, pure Java When to Use a Headless Browser for Your Testing? So when should you use headless browsing for your testing? As you can see, it depends on your testing goals. People on the left will often say, “Never use a headless browser. A real user would never use it so why should you? ” Meanwhile, folks on the right will say, “You should always use headless browsers because they’re always faster, and faster is always better. ” As we well know, however, it’s not always one versus the other, but rather a matter of selecting the right tool for the rights task depending on the situation. Remember–use the right tool for the job and always ask yourself how it will affect the end users and what the goal(s) of your test are when decided between the two approaches.

Frequently Asked Questions about headless javascript testing

What is headless mode in testing?

Headless testing is simply running your Selenium tests using a headless browser. It operates as your typical browser would, but without a user interface, making it excellent for automated testing.Oct 8, 2019

What is headless UI testing?

Headless testing is when you run a UI-based browser test without showing the browser UI. It’s running a test or running a script against a browser but without the browser, UI starting up.Sep 21, 2020

What are the best headless browsers for testing?

6 Popular Headless Browsers for Web TestingFirefox headless mode.Headless Chrome.PhantomJS.Zombie.js.HtmlUnit.Splash.Feb 22, 2018

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