This PR updates the troubleshooting guide with some information regarding the new `exports` resolution and cache directory. This PR also reformats some of the other MD documents.
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Puppeteer
API | FAQ | Contributing | Troubleshooting
Puppeteer is a Node.js library which provides a high-level API to control Chrome/Chromium over the DevTools Protocol. Puppeteer runs in headless mode by default, but can be configured to run in full (non-headless) Chrome/Chromium.
What can I do?
Most things that you can do manually in the browser can be done using Puppeteer! Here are a few examples to get you started:
- Generate screenshots and PDFs of pages.
- Crawl a SPA (Single-Page Application) and generate pre-rendered content (i.e. "SSR" (Server-Side Rendering)).
- Automate form submission, UI testing, keyboard input, etc.
- Create an automated testing environment using the latest JavaScript and browser features.
- Capture a timeline trace of your site to help diagnose performance issues.
- Test Chrome Extensions.
Getting Started
Installation
To use Puppeteer in your project, run:
npm i puppeteer
# or `yarn add puppeteer`
# or `pnpm i puppeteer`
When you install Puppeteer, it automatically downloads a recent version of
Chromium (~170MB macOS, ~282MB Linux, ~280MB Windows) that is
guaranteed to work
with Puppeteer. For a version of Puppeteer without installation, see
puppeteer-core
.
Environment Variables
Puppeteer looks for certain environment variables for customizing behavior. If Puppeteer doesn't find them in the environment during the installation step, a lowercased variant of these variables will be used from the npm config.
HTTP_PROXY
,HTTPS_PROXY
,NO_PROXY
- defines HTTP proxy settings that are used to download and run the browser.PUPPETEER_CACHE_DIR
- defines the directory to be used by Puppeteer for caching. Defaults toos.homedir()/.cache/puppeteer
.PUPPETEER_SKIP_CHROMIUM_DOWNLOAD
- do not download bundled Chromium during installation step.PUPPETEER_TMP_DIR
- defines the directory to be used by Puppeteer for creating temporary files. Defaults toos.tmpdir()
.PUPPETEER_DOWNLOAD_HOST
- specifies the URL prefix that is used to download Chromium. Note: this includes protocol and might even include path prefix. Defaults tohttps://storage.googleapis.com
.PUPPETEER_DOWNLOAD_PATH
- specifies the path for the downloads folder. Defaults to<cache>/chromium
, where<cache>
is Puppeteer's cache directory.PUPPETEER_BROWSER_REVISION
- specifies a certain version of the browser you'd like Puppeteer to use. Seepuppeteer.launch
on how executable path is inferred.PUPPETEER_EXECUTABLE_PATH
- specifies an executable path to be used inpuppeteer.launch
.PUPPETEER_PRODUCT
- specifies which browser you'd like Puppeteer to use. Must be eitherchrome
orfirefox
. This can also be used during installation to fetch the recommended browser binary. Settingproduct
programmatically inpuppeteer.launch
supersedes this environment variable.PUPPETEER_EXPERIMENTAL_CHROMIUM_MAC_ARM
— specify Puppeteer download Chromium for Apple M1. On Apple M1 devices Puppeteer by default downloads the version for Intel's processor which runs via Rosetta. It works without any problems, however, with this option, you should get more efficient resource usage (CPU and RAM) that could lead to a faster execution time.
Environment variables except for PUPPETEER_CACHE_DIR
are not used for
puppeteer-core
since core does not automatically handle
browser downloading.
puppeteer-core
Every release since v1.7.0 we publish two packages:
puppeteer
is a product for browser automation. When installed, it downloads
a version of Chromium, which it then drives using puppeteer-core
. Being an
end-user product, puppeteer
supports a bunch of convenient PUPPETEER_*
env
variables to tweak its behavior.
puppeteer-core
is a library to help drive anything that supports DevTools
protocol. puppeteer-core
doesn't download Chromium when installed. Being a
library, puppeteer-core
is fully driven through its programmatic interface.
You should only use puppeteer-core
if you are
connecting to a remote browser
or managing browsers yourself.
If you are managing browsers yourself, you will need to call
puppeteer.launch
with
an explicit
executablePath
or channel
.
When using puppeteer-core
, remember to change the import:
import puppeteer from 'puppeteer-core';
Usage
Puppeteer follows the latest maintenance LTS version of Node.
Puppeteer will be familiar to people using other browser testing frameworks. You launch/connect a browser, create some pages, and then manipulate them with Puppeteer's API.
For more in-depth usage, check our guides and examples.
Example
The following example searches developers.google.com/web for articles tagged "Headless Chrome" and scrape results from the results page.
import puppeteer from 'puppeteer';
(async () => {
const browser = await puppeteer.launch();
const page = await browser.newPage();
await page.goto('https://developers.google.com/web/');
// Type into search box.
await page.type('.devsite-search-field', 'Headless Chrome');
// Wait for suggest overlay to appear and click "show all results".
const allResultsSelector = '.devsite-suggest-all-results';
await page.waitForSelector(allResultsSelector);
await page.click(allResultsSelector);
// Wait for the results page to load and display the results.
const resultsSelector = '.gsc-results .gs-title';
await page.waitForSelector(resultsSelector);
// Extract the results from the page.
const links = await page.evaluate(resultsSelector => {
return [...document.querySelectorAll(resultsSelector)].map(anchor => {
const title = anchor.textContent.split('|')[0].trim();
return `${title} - ${anchor.href}`;
});
}, resultsSelector);
// Print all the files.
console.log(links.join('\n'));
await browser.close();
})();
Default runtime settings
1. Uses Headless mode
Puppeteer launches Chromium in
headless mode.
To launch a full version of Chromium, set the
headless
option when launching a browser:
const browser = await puppeteer.launch({headless: false}); // default is true
2. Runs a bundled version of Chromium
By default, Puppeteer downloads and uses a specific version of Chromium so its
API is guaranteed to work out of the box. To use Puppeteer with a different
version of Chrome or Chromium, pass in the executable's path when creating a
Browser
instance:
const browser = await puppeteer.launch({executablePath: '/path/to/Chrome'});
You can also use Puppeteer with Firefox Nightly (experimental support). See
Puppeteer.launch
for
more information.
See
this article
for a description of the differences between Chromium and Chrome.
This article
describes some differences for Linux users.
3. Creates a fresh user profile
Puppeteer creates its own browser user profile which it cleans up on every run.
Using Docker
See our guide on using Docker.
Using Chrome Extensions
See our guide on using Chrome extensions.
Resources
Contributing
Check out our contributing guide to get an overview of Puppeteer development.