b2d2bf822a
This patch: - renames Page.printToPDF into page.pdf - adds a 'path' option to the page.pdf options instead of a separate `filePath` parameter - improves on the documentation for the `page.pdf` References #39.
4.7 KiB
Puppeteer 
Puppeteer is a Node library which provides a high-level API to control Chromium over the DevTools Protocol. Puppeteer is inspired by PhantomJS. Check our FAQ to learn more.
Use Cases
- Up-to-date testing environment that supports the latest Javascript features.
- Crawl your site to generate pre-rendered content for your SPA.
- Scrape content from websites.
Installation
Get the source:
git clone https://github.com/GoogleChrome/puppeteer
cd puppeteer
Install the dependencies:
yarn
or use npm:
npm install
Note: Puppeteer bundles Chromium (~70Mb) which it is guaranteed to work with. However, you're free to point Puppeteer to any Chromium executable (example)
Getting Started
The following script navigates to https://example.com and saves a screenshot to example.png:
const Browser = require('Puppeteer').Browser;
const browser = new Browser();
browser.newPage().then(async page => {
await page.navigate('https://example.com');
await page.screenshot({path: 'example.png'});
browser.close();
});
A few notes:
- By default, Puppeteer runs a bundled Chromium browser. However, you can point Puppeteer to a different executable (example)
- Puppeteer creates its own Chromium user profile which it cleans up on every run.
- Puppeteer sets an initial page size to 400px x 300px, which defines the screenshot size. The page size can be changed with
Page.setViewportSize()method
API
API documentation is a work in progress.
Contributing
Check out our contributing guide
FAQ
Q: What is Puppeteer?
Puppeteer is a light-weight Node module to control headless Chrome using the DevTools Protocol.
Q: Does Puppeteer work with headless Chromium?
Yes. Puppeteer bundles a version of Chromium and runs it in headless mode by default.
Q: How is Puppeteer different than PhantomJS?
While PhantomJS provides a JavaScript API to control a full-fledged browser (WebKit), Puppeteer is a light-weight Node module to control headless Chrome.
Other important differences:
- Uses an evergreen browser - Puppeteer uses headless Chromium, which means it can access all the latest web platform features offered by the Blink rendering engine.
- Improved debuggability - thanks to Node debugging in Chrome DevTools.
Q: Which Chromium version does Puppeteer use?
[TODO]
Q: How do I migrate from PhantomJS to Puppeteer?
There's no automatic way to migrate PhantomJS scripts to Node scripts with Puppeteer. For more information and some guidance, check out our migration guide.
Q: Why do most of the API methods return promises?
Since Puppeteer's code is run by Node, it exists out-of-process to the controlled Chromium instance. This requires most of the API calls to be asynchronous to allow the necessary roundtrips to the browser.
However, if you're using Node 8 or higher, async/await make life easier:
browser.newPage().then(async page => {
await page.setViewportSize({width: 1000, height: 1000});
await page.pdf({path: 'blank.pdf'});
browser.close();
});
Q: What is the "Phantom Shim"?
"Phantom Shim" is a layer built atop the Puppeteer API that simulates Phantom's environment.
Puppeteer's process model is different than Phantom's. Puppeteer runs out-of-process to the browser, whereas Phantom runs in-process. To simulate in-process behavior, phantom_shim hacks Node's runtime with nested event loops) to simulate in-process operation. This might result in unpredictable side-effects and makes the shim unreliable for certain use cases situations.
Q: What is the difference between Puppeteer and Selenium / WebDriver?
Selenium / WebDriver is a well-established cross-browser API that is useful for testing cross-browser support.
Puppeteer is useful for single-browser testing. For example, many teams only run unit tests with a single browser (e.g. Phantom). In non-testing use cases, Puppeteer provides a powerful but simple API because it's only targeting one browser that enables you to rapidly develop automation scripts.
Migration Guide
[TODO]