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Headless Chrome is shipping in Chrome It's a way to run the Chrome browser in a headless environment. Essentially, running Chrome without chrome! It brings all modern web platform features provided by Chromium and the Blink rendering engine to the command line.
A headless browser is a great tool for automated testing and server environments where you don't need a visible UI shell.
For example, you may want to run some tests against a real web page, create a PDF of it, or just inspect how the browser renders an URL. The easiest way to get started with headless mode is to open the Chrome binary from the command line. The exact location will vary from platform to platform. If you're on the stable channel of Chrome and cannot get the Beta, I recommend using chrome-canary:. In some cases, you may not need to programmatically script Headless Chrome.
There are some useful command line flags to perform common tasks. Running with --screenshot will produce a file named screenshot. If you're looking for full page screenshots, things are a tad more involved. There's a great blog post from David Schnurr that has you covered. Check out Using headless Chrome as an automated screenshot tool. The --repl flag runs Headless in a mode where you can evaluate JS expressions in the browser, right from the command line:.
The protocol is used to communicate with Chrome and drive the headless browser instance. Since you don't have browser UI to see the page, navigate to http: You'll see a list of inspectable pages where you can click through and see what Headless is rendering:. From here, you can use the familiar DevTools features to inspect, debug, and tweak the page as you normally would. If you're using Headless programmatically, this page is also a powerful debugging tool for seeing all the raw DevTools protocol commands going across the wire, communicating with the browser.
Puppeteer is a Node library developed by the Chrome team. It provides a high-level API to control headless or full Chrome. It's similar to other automated testing libraries like Phantom and NightmareJS, but it only works with the latest versions of Chrome. Among other things, Puppeteer can be used to easily take screenshots, create PDFs, navigate pages, and fetch information about those pages.
I recommend the library if you want to quickly automate browser testing. It hides away the complexities of the DevTools protocol and takes care of redundant tasks like launching a debug instance of Chrome. Check out Puppeteer's documentation to learn more about the full API. I recommend it if you want to be close to the metal and use the DevTools protocol directly. However, to fully automate tests, you'll probably want to spawn Chrome from your application.
But things get tricky if you want a portable solution that works across multiple platforms. Just look at that hard-coded path to Chrome: Lighthouse is a marvelous tool for testing the quality of your web apps.
A robust module for launching Chrome was developed within Lighthouse and is now extracted for standalone use. The chrome-launcher NPM module will find where Chrome is installed, set up a debug instance, launch the browser, and kill it when your program is done. Best part is that it works cross-platform thanks to Node! By default, chrome-launcher will try to launch Chrome Canary if it's installed , but you can change that to manually select which Chrome to use. To use it, first install from npm:.
Running this script doesn't do much, but you should see an instance of Chrome fire up in the task manager that loaded about: Remember, there won't be any browser UI. Example - check if the site has a web app manifest. Right now, Selenium opens a full instance of Chrome. In other words, it's an automated solution but not completely headless. However, Selenium can be configured to run headless Chrome with a little work. I recommend Running Selenium with Headless Chrome if you want the full instructions on how to set things up yourself, but I've dropped in some examples below to get you started.
Other platforms no longer require it. The --disable-gpu flag is a temporary work around for a few bugs. You won't need this flag in future versions of Chrome. Headless Chrome doesn't use a window so a display server like Xvfb is no longer needed.
You can happily run your automated tests without it. Xvfb is an in-memory display server for Unix-like systems that enables you to run graphical applications like Chrome without an attached physical display. Many people use Xvfb to run earlier versions of Chrome to do "headless" testing.
It has an example Dockerfile that uses node: Headless Chrome is similar to tools like PhantomJS. Both can be used for automated testing in a headless environment. The main difference between the two is that Phantom uses an older version of WebKit as its rendering engine while Headless Chrome uses the latest version of Blink. For bugs against Headless Chrome, file them on crbug. For bugs in the DevTools protocol, file them at github.
Except as otherwise noted, the content of this page is licensed under the Creative Commons Attribution 3. For details, see our Site Policies. Last updated February 26, Be there and be square. Why Should You Care? A Memory-Saving Experiment Using the web app manifest to specify a site wide theme colour Using the web app manifest to create a solid color loading screen Using requestIdleCallback The larger-than advanced Network Panel filter, and a few others DevTools Digest: Film strip and a new home for throttling Interact with Bluetooth devices on the Web Add a new custom device as a preset MediaStream Deprecations Media playback notifications for Chrome on Android Measuring Performance in a Service Worker Using rotationAngle and touchRadius Inspect and trigger CSS media queries Shortcut to select the next occurrence Select and execute a block of code in the Sources Panel Set a breakpoint based on a certain condition Quickly cycle through the DevTools panels Print out a quick stack trace from the Console Who inspects the inspector?
Chrome Dev Summit Let's build some apps with Polymer! Platforms Summary Chrome Dev Summit: Performance Summary Chrome Dev Summit: Polymer declarative, encapsulated, reusable components Chrome Dev Summit: Flexbox layout isn't slow September DevTools answers: What font is that?
Stacking Changes Coming to position: Have I got your attention? Engineer Google working on web tooling: Headless Chrome, Puppeteer, Lighthouse.