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Playwright
API | FAQ | Contributing
Playwright is a Node library to automate the Chromium, WebKit and Firefox browsers. Playwright is focused on enabling cross-browser web automation platform that is ever-green, capable, reliable and fast. Our primary goal with Playwright is to improve automated UI testing by eliminating flakiness, improving the speed of execution and offering insights into the browser operation. Playwright runs headless versions of these browsers by default, but can be configured to run the full versions.
Installation
npm i playwright
This installs Playwright along with its dependencies and the browser binaries. Browser binaries are about 50-100MB each, so expect the installation network traffic to be substantial.
Usage
Playwright can be used to create a browser instance, open pages, and then manipulate them. See API docs for a comprehensive list.
Examples
Page screenshot
This code snippet navigates to example.com in WebKit, and saves a screenshot.
const pw = require('playwright');
(async () => {
const browser = await pw.playwright('webkit').launch(); // or 'chromium', 'firefox'
const context = await browser.newContext();
const page = await context.newPage();
await page.goto('https://www.example.com/');
await page.screenshot({ path: 'example.png' });
await browser.close();
})();
Evaluate script
This code snippet navigates to example.com in Firefox, and executes a script in the page context.
const pw = require('playwright');
(async () => {
const browser = await pw.playwright('firefox').launch(); // or 'chromium', 'webkit'
const context = await browser.newContext();
const page = await context.newPage();
await page.goto('https://www.example.com/');
const dimensions = await page.evaluate(() => {
return {
width: document.documentElement.clientWidth,
height: document.documentElement.clientHeight,
deviceScaleFactor: window.devicePixelRatio
}
})
console.log(dimensions);
await browser.close();
})();
Limitations
WebKit support on Windows is based on the WSL / Docker containers. We are working on the WinCairo-based version of the browser, but it'll be available later. Stay tuned!
Contributing to Playwright
Check out our contributing guide.
FAQ
Q: How does Playwright relate to Puppeteer?
We are the same team that built Puppeteer. Puppeteer proved that there is a lot of interest in the new generation of ever-green, capable and reliable automation drivers. With Playwright, we'd like to take it one step further and offer the same functionality for all the popular rendering engines. We'd like to see Playwright vendor-neutral and shared goverened.
With Playwright, we are making the APIs more testing friendly as well. We are taking the lessons learned from Puppeteer and incorporate them into the API, for example, user agent / device emulation is set up consistently on the BrowserContext level to enable multi-page scenarios, click now waits for the element to be available and visible by default, etc.
Playwright also aims at being even more cloud-friendly. Rather than a single page, BrowserContext abstraction is now central to the library operation. BrowserContexts are isolated, they can be either created locally or provided by the server-side factories.
All the changes and improvements above would require breaking changes to the Puppeteer API, so we chose to start with a clean slate instead. Due to the similarity of the concepts and the APIs, migration between the two is still a mechanical task.
Q: What about the WebDriver?
WIP
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[capabilities] With Playwright, we aim at providing a more capable driver, including support for mobile viewports, touch, web & service workers, geolocation, csp, cookie policies, permissions, accessibility, etc.
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[reliability] Playwright's communication with all the browsers is event-driven, based on the full-duplex transport, which eliminates the need for polling. (Polling is one of the greatest sources of test flakiness).
Q: Is Playwright ready?
Playwright is ready for your feedback. It respects semver, so please expect some API breakages as we release 1.0. All we can promise is that those breakages are going to be based on your feedback with the sole purpose of making our APIs better.
Playwright is being actively developed as we get to the feature parity across Chromium, Firefox and WebKit. Progress on each browser can be tracked on the Is Playwright Ready? page, which shows currently failing tests per browser.