thunderstrike/puppeteer
2
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

feat: add documentation (#8593)

Browse Source
This commit is contained in:
jrandolf
2022-07-01 13:52:39 +02:00
committed by GitHub
parent 51ae338acd
commit 066f440ba7
781 changed files with 55939 additions and 7515 deletions
Download Patch File Download Diff File Expand all files Collapse all files

338
README.md
View File

@@ -1,3 +1,7 @@
---
sidebar_position: 1
---
# Puppeteer
<!-- [START badges] -->
@@ -6,15 +10,15 @@
<!-- [END badges] -->
<img src="https://user-images.githubusercontent.com/10379601/29446482-04f7036a-841f-11e7-9872-91d1fc2ea683.png" height="200" align="right">
<img src="https://user-images.githubusercontent.com/10379601/29446482-04f7036a-841f-11e7-9872-91d1fc2ea683.png" height="200" align="right"/>
###### [API](https://github.com/puppeteer/puppeteer/blob/v15.2.0/docs/api.md) | [FAQ](#faq) | [Contributing](https://github.com/puppeteer/puppeteer/blob/main/CONTRIBUTING.md) | [Troubleshooting](https://github.com/puppeteer/puppeteer/blob/main/docs/troubleshooting.md)
###### [API](https://pptr.dev/api) | [FAQ](https://pptr.dev/faq) | [Contributing](https://pptr.dev/contributing) | [Troubleshooting](https://pptr.dev/troubleshooting)
> Puppeteer is a Node library which provides a high-level API to control Chrome or Chromium over the [DevTools Protocol](https://chromedevtools.github.io/devtools-protocol/). Puppeteer runs [headless](https://developers.google.com/web/updates/2017/04/headless-chrome) by default, but can be configured to run full (non-headless) Chrome or Chromium.
<!-- [START usecases] -->
###### What can I do?
##### 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:
@@ -39,37 +43,81 @@ npm i puppeteer
# or "yarn add puppeteer"
```
Note: When you install Puppeteer, it downloads a recent version of Chromium (~170MB Mac, ~282MB Linux, ~280MB Win) that is guaranteed to work with the API. To skip the download, download into another path, or download a different browser, see [Environment variables](https://github.com/puppeteer/puppeteer/blob/v15.2.0/docs/api.md#environment-variables).
When you install Puppeteer, it downloads a recent version of Chromium (~170MB Mac, ~282MB Linux, ~280MB Win) that is guaranteed to work with the API (customizable through [Environment Variables](#environment-variables)). For a version of Puppeteer purely for connection, see [`puppeteer-core`](#puppeteer-core).
### puppeteer-core
#### Environment Variables
Since version 1.7.0 we publish the [`puppeteer-core`](https://www.npmjs.com/package/puppeteer-core) package,
a version of Puppeteer that doesn't download any browser by default.
Puppeteer looks for certain [environment variables](https://en.wikipedia.org/wiki/Environment_variable) to aid its operations.
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](https://docs.npmjs.com/cli/config).
```bash
npm i puppeteer-core
# or "yarn add puppeteer-core"
- `HTTP_PROXY`, `HTTPS_PROXY`, `NO_PROXY` - defines HTTP proxy settings that are used to download and run the browser.
- `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 to [`os.tmpdir()`](https://nodejs.org/api/os.html#os_os_tmpdir).
- `PUPPETEER_DOWNLOAD_HOST` - overwrite URL prefix that is used to download Chromium. Note: this includes protocol and might even include path prefix. Defaults to `https://storage.googleapis.com`.
- `PUPPETEER_DOWNLOAD_PATH` - overwrite the path for the downloads folder. Defaults to `<root>/.local-chromium`, where `<root>` is Puppeteer's package root.
- `PUPPETEER_CHROMIUM_REVISION` - specify a certain version of Chromium you'd like Puppeteer to use. See [`puppeteer.launch`](https://pptr.dev/api/puppeteer.puppeteernode.launch) on how executable path is inferred.
- `PUPPETEER_EXECUTABLE_PATH` - specify an executable path to be used in [`puppeteer.launch`](https://pptr.dev/api/puppeteer.puppeteernode.launch).
- `PUPPETEER_PRODUCT` - specify which browser you'd like Puppeteer to use. Must be one of `chrome` or `firefox`. This can also be used during installation to fetch the recommended browser binary. Setting `product` programmatically in [`puppeteer.launch`](https://pptr.dev/api/puppeteer.puppeteernode.launch) supersedes this environment variable. The product is exposed in [`puppeteer.product`](https://pptr.dev/api/puppeteer.product)
- `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.
:::danger
Puppeteer is only [guaranteed to work](https://pptr.dev/faq#q-why-doesnt-puppeteer-vxxx-work-with-chromium-vyyy) with the bundled Chromium, use at your own risk.
:::
:::caution
`PUPPETEER_*` env variables are not accounted for in [`puppeteer-core`](#puppeteer-core).
:::
#### puppeteer-core
Every release since v1.7.0 we publish two packages:
- [`puppeteer`](https://www.npmjs.com/package/puppeteer)
- [`puppeteer-core`](https://www.npmjs.com/package/puppeteer-core)
`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 and disregards all the `PUPPETEER_*` env variables.
To sum up, the only differences between `puppeteer-core` and `puppeteer` are:
- `puppeteer-core` doesn't automatically download Chromium when installed.
- `puppeteer-core` ignores all `PUPPETEER_*` env variables.
In most cases, you'll be fine using the `puppeteer` package.
However, you should use `puppeteer-core` if:
- you're building another end-user product or library atop of DevTools protocol. For example, one might build a PDF generator using `puppeteer-core` and write a custom `install.js` script that downloads [`headless_shell`](https://chromium.googlesource.com/chromium/src/+/lkgr/headless/README.md) instead of Chromium to save disk space.
- you're bundling Puppeteer to use in Chrome Extension / browser with the DevTools protocol where downloading an additional Chromium binary is unnecessary.
- you're building a set of tools where `puppeteer-core` is one of the ingredients and you want to postpone `install.js` script execution until Chromium is about to be used.
When using `puppeteer-core`, remember to change the _include_ line:
```ts
const puppeteer = require('puppeteer-core');
```
`puppeteer-core` is intended to be a lightweight version of Puppeteer for launching an existing browser installation or for connecting to a remote one. Be sure that the version of puppeteer-core you install is compatible with the browser you intend to connect to.
See [puppeteer vs puppeteer-core](https://github.com/puppeteer/puppeteer/blob/v15.2.0/docs/api.md#puppeteer-vs-puppeteer-core).
You will then need to call [`puppeteer.connect`](https://pptr.dev/api/puppeteer.puppeteer.connect) or [`puppeteer.launch`](https://pptr.dev/api/puppeteer.puppeteernode.launch) with an explicit `executablePath` or `channel` option.
### Usage
Puppeteer follows the latest [maintenance LTS](https://github.com/nodejs/Release#release-schedule) version of Node.
Note: Prior to v1.18.1, Puppeteer required at least Node v6.4.0. Versions from v1.18.1 to v2.1.0 rely on
Node 8.9.0+. Starting from v3.0.0 Puppeteer starts to rely on Node 10.18.1+. All examples below use async/await which is only supported in Node v7.6.0 or greater.
Puppeteer will be familiar to people using other browser testing frameworks. You create an instance
of `Browser`, open pages, and then manipulate them with [Puppeteer's API](https://github.com/puppeteer/puppeteer/blob/v15.2.0/docs/api.md#).
of `Browser`, open pages, and then manipulate them with [Puppeteer's API](https://pptr.dev/api).
**Example** - navigating to https://example.com and saving a screenshot as _example.png_:
Save file as **example.js**
```js
```ts
const puppeteer = require('puppeteer');
(async () => {
@@ -88,13 +136,13 @@ Execute script on the command line
node example.js
```
Puppeteer sets an initial page size to 800×600px, which defines the screenshot size. The page size can be customized with [`Page.setViewport()`](https://github.com/puppeteer/puppeteer/blob/v15.2.0/docs/api.md#pagesetviewportviewport).
Puppeteer sets an initial page size to 800×600px, which defines the screenshot size. The page size can be customized with [`Page.setViewport()`](https://pptr.dev/api/puppeteer.page.setviewport).
**Example** - create a PDF.
Save file as **hn.js**
```js
```ts
const puppeteer = require('puppeteer');
(async () => {
@@ -115,13 +163,13 @@ Execute script on the command line
node hn.js
```
See [`Page.pdf()`](https://github.com/puppeteer/puppeteer/blob/v15.2.0/docs/api.md#pagepdfoptions) for more information about creating pdfs.
See [`Page.pdf`](https://pptr.dev/api/puppeteer.page.pdf) for more information about creating pdfs.
**Example** - evaluate script in the context of the page
Save file as **get-dimensions.js**
```js
```ts
const puppeteer = require('puppeteer');
(async () => {
@@ -150,19 +198,64 @@ Execute script on the command line
node get-dimensions.js
```
See [`Page.evaluate()`](https://github.com/puppeteer/puppeteer/blob/v15.2.0/docs/api.md#pageevaluatepagefunction-args) for more information on `evaluate` and related methods like `evaluateOnNewDocument` and `exposeFunction`.
See [`Page.evaluate`](https://pptr.dev/api/puppeteer.page.evaluate) and related methods like [`Page.evaluateOnNewDocument`](https://pptr.dev/api/puppeteer.page.evaluateOnNewDocument) and [`Page.exposeFunction`](https://pptr.dev/api/puppeteer.page.exposeFunction).
<!-- [END getstarted] -->
### Working with Chrome Extensions
Puppeteer can be used for testing Chrome Extensions.
:::caution
Extensions in Chrome / Chromium currently only work in non-headless mode and experimental Chrome headless mode.
:::
The following is code for getting a handle to the [background page](https://developer.chrome.com/extensions/background_pages) of an extension whose source is located in `./my-extension`:
```ts
const puppeteer = require('puppeteer');
(async () => {
const pathToExtension = require('path').join(__dirname, 'my-extension');
const browser = await puppeteer.launch({
headless: 'chrome',
args: [
`--disable-extensions-except=${pathToExtension}`,
`--load-extension=${pathToExtension}`,
],
});
const backgroundPageTarget = await browser.waitForTarget(
target => target.type() === 'background_page'
);
const backgroundPage = await backgroundPageTarget.page();
// Test the background page as you would any other page.
await browser.close();
})();
```
:::note
Chrome Manifest V3 extensions have a background ServiceWorker of type 'service_worker', instead of a page of type 'background_page'.
:::
:::note
It is not yet possible to test extension popups or content scripts.
:::
<!-- [START runtimesettings] -->
## Default runtime settings
**1. Uses Headless mode**
Puppeteer launches Chromium in [headless mode](https://developers.google.com/web/updates/2017/04/headless-chrome). To launch a full version of Chromium, set the [`headless` option](https://github.com/puppeteer/puppeteer/blob/v15.2.0/docs/api.md#puppeteerlaunchoptions) when launching a browser:
Puppeteer launches Chromium in [headless mode](https://developers.google.com/web/updates/2017/04/headless-chrome). To launch a full version of Chromium, set the [`headless` option](https://pptr.dev/api/puppeteer.browserlaunchargumentoptions.headless) when launching a browser:
```js
```ts
const browser = await puppeteer.launch({headless: false}); // default is true
```
@@ -172,11 +265,11 @@ By default, Puppeteer downloads and uses a specific version of Chromium so its A
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:
```js
```ts
const browser = await puppeteer.launch({executablePath: '/path/to/Chrome'});
```
You can also use Puppeteer with Firefox Nightly (experimental support). See [`Puppeteer.launch()`](https://github.com/puppeteer/puppeteer/blob/v15.2.0/docs/api.md#puppeteerlaunchoptions) for more information.
You can also use Puppeteer with Firefox Nightly (experimental support). See [`Puppeteer.launch`](https://pptr.dev/api/puppeteer.puppeteernode.launch) for more information.
See [`this article`](https://www.howtogeek.com/202825/what%E2%80%99s-the-difference-between-chromium-and-chrome/) for a description of the differences between Chromium and Chrome. [`This article`](https://chromium.googlesource.com/chromium/src/+/refs/heads/main/docs/chromium_browser_vs_google_chrome.md) describes some differences for Linux users.
@@ -188,8 +281,8 @@ Puppeteer creates its own browser user profile which it **cleans up on every run
## Resources
- [API Documentation](https://github.com/puppeteer/puppeteer/blob/v15.2.0/docs/api.md)
- [Examples](https://github.com/puppeteer/puppeteer/tree/main/examples/)
- [API Documentation](https://pptr.dev/api)
- [Examples](https://github.com/puppeteer/puppeteer/tree/main/examples)
- [Community list of Puppeteer resources](https://github.com/transitive-bullshit/awesome-puppeteer)
<!-- [START debugging] -->
@@ -200,14 +293,14 @@ Puppeteer creates its own browser user profile which it **cleans up on every run
displaying. Instead of launching in headless mode, launch a full version of
the browser using `headless: false`:
```js
```ts
const browser = await puppeteer.launch({headless: false});
```
2. Slow it down - the `slowMo` option slows down Puppeteer operations by the
specified amount of milliseconds. It's another way to help see what's going on.
```js
```ts
const browser = await puppeteer.launch({
headless: false,
slowMo: 250, // slow down by 250ms
@@ -217,7 +310,7 @@ Puppeteer creates its own browser user profile which it **cleans up on every run
3. Capture console output - You can listen for the `console` event.
This is also handy when debugging code in `page.evaluate()`:
```js
```ts
page.on('console', msg => console.log('PAGE LOG:', msg.text()));
await page.evaluate(() => console.log(`url is ${location.href}`));
@@ -231,7 +324,7 @@ Puppeteer creates its own browser user profile which it **cleans up on every run
- Use `{devtools: true}` when launching Puppeteer:
```js
```ts
const browser = await puppeteer.launch({devtools: true});
```
@@ -245,7 +338,7 @@ Puppeteer creates its own browser user profile which it **cleans up on every run
- Add an evaluate statement with `debugger` inside / add `debugger` to an existing evaluate statement:
```js
```ts
await page.evaluate(() => {
debugger;
});
@@ -263,7 +356,7 @@ Puppeteer creates its own browser user profile which it **cleans up on every run
- Add `debugger;` to your test, eg:
```js
```ts
debugger;
await page.click('a[target=_blank]');
```
@@ -297,177 +390,10 @@ Puppeteer creates its own browser user profile which it **cleans up on every run
<!-- [END debugging] -->
<!-- [START typescript] -->
## Contributing
## Usage with TypeScript
Check out our [contributing guide](https://pptr.dev/contributing) to get an overview of Puppeteer development.
We have recently completed a migration to move the Puppeteer source code from JavaScript to TypeScript and as of version 7.0.1 we ship our own built-in type definitions.
## FAQ
If you are on a version older than 7, we recommend installing the Puppeteer type definitions from the [DefinitelyTyped](https://definitelytyped.org/) repository:
```bash
npm install --save-dev @types/puppeteer
```
The types that you'll see appearing in the Puppeteer source code are based off the great work of those who have contributed to the `@types/puppeteer` package. We really appreciate the hard work those people put in to providing high quality TypeScript definitions for Puppeteer's users.
<!-- [END typescript] -->
## Contributing to Puppeteer
Check out [contributing guide](https://github.com/puppeteer/puppeteer/blob/main/CONTRIBUTING.md) to get an overview of Puppeteer development.
<!-- [START faq] -->
# FAQ
#### Q: Who maintains Puppeteer?
The Chrome DevTools team maintains the library, but we'd love your help and expertise on the project!
See [Contributing](https://github.com/puppeteer/puppeteer/blob/main/CONTRIBUTING.md).
#### Q: What is the status of cross-browser support?
Official Firefox support is currently experimental. The ongoing collaboration with Mozilla aims to support common end-to-end testing use cases, for which developers expect cross-browser coverage. The Puppeteer team needs input from users to stabilize Firefox support and to bring missing APIs to our attention.
From Puppeteer v2.1.0 onwards you can specify [`puppeteer.launch({product: 'firefox'})`](https://github.com/puppeteer/puppeteer/blob/v15.2.0/docs/api.md#puppeteerlaunchoptions) to run your Puppeteer scripts in Firefox Nightly, without any additional custom patches. While [an older experiment](https://www.npmjs.com/package/puppeteer-firefox) required a patched version of Firefox, [the current approach](https://wiki.mozilla.org/Remote) works with “stock” Firefox.
We will continue to collaborate with other browser vendors to bring Puppeteer support to browsers such as Safari.
This effort includes exploration of a standard for executing cross-browser commands (instead of relying on the non-standard DevTools Protocol used by Chrome).
#### Q: What are Puppeteer’s goals and principles?
The goals of the project are:
- Provide a slim, canonical library that highlights the capabilities of the [DevTools Protocol](https://chromedevtools.github.io/devtools-protocol/).
- Provide a reference implementation for similar testing libraries. Eventually, these other frameworks could adopt Puppeteer as their foundational layer.
- Grow the adoption of headless/automated browser testing.
- Help dogfood new DevTools Protocol features...and catch bugs!
- Learn more about the pain points of automated browser testing and help fill those gaps.
We adapt [Chromium principles](https://www.chromium.org/developers/core-principles) to help us drive product decisions:
- **Speed**: Puppeteer has almost zero performance overhead over an automated page.
- **Security**: Puppeteer operates off-process with respect to Chromium, making it safe to automate potentially malicious pages.
- **Stability**: Puppeteer should not be flaky and should not leak memory.
- **Simplicity**: Puppeteer provides a high-level API that’s easy to use, understand, and debug.
#### Q: Is Puppeteer replacing Selenium/WebDriver?
**No**. Both projects are valuable for very different reasons:
- Selenium/WebDriver focuses on cross-browser automation; its value proposition is a single standard API that works across all major browsers.
- Puppeteer focuses on Chromium; its value proposition is richer functionality and higher reliability.
That said, you **can** use Puppeteer to run tests against Chromium, e.g. using the community-driven [jest-puppeteer](https://github.com/smooth-code/jest-puppeteer). While this probably shouldn’t be your only testing solution, it does have a few good points compared to WebDriver:
- Puppeteer requires zero setup and comes bundled with the Chromium version it works best with, making it [very easy to start with](https://github.com/puppeteer/puppeteer/#getting-started). At the end of the day, it’s better to have a few tests running chromium-only, than no tests at all.
- Puppeteer has event-driven architecture, which removes a lot of potential flakiness. There’s no need for evil “sleep(1000)” calls in puppeteer scripts.
- Puppeteer runs headless by default, which makes it fast to run. Puppeteer v1.5.0 also exposes browser contexts, making it possible to efficiently parallelize test execution.
- Puppeteer shines when it comes to debugging: flip the “headless” bit to false, add “slowMo”, and you’ll see what the browser is doing. You can even open Chrome DevTools to inspect the test environment.
#### Q: Why doesn’t Puppeteer v.XXX work with Chromium v.YYY?
We see Puppeteer as an **indivisible entity** with Chromium. Each version of Puppeteer bundles a specific version of Chromium – **the only** version it is guaranteed to work with.
This is not an artificial constraint: A lot of work on Puppeteer is actually taking place in the Chromium repository. Here’s a typical story:
- A Puppeteer bug is reported: https://github.com/puppeteer/puppeteer/issues/2709
- It turned out this is an issue with the DevTools protocol, so we’re fixing it in Chromium: https://chromium-review.googlesource.com/c/chromium/src/+/1102154
- Once the upstream fix is landed, we roll updated Chromium into Puppeteer: https://github.com/puppeteer/puppeteer/pull/2769
However, oftentimes it is desirable to use Puppeteer with the official Google Chrome rather than Chromium. For this to work, you should install a `puppeteer-core` version that corresponds to the Chrome version.
For example, in order to drive Chrome 71 with puppeteer-core, use `chrome-71` npm tag:
```bash
npm install puppeteer-core@chrome-71
```
#### Q: Which Chromium version does Puppeteer use?
Find the version using one of the following ways:
- Look for the `chromium` entry in [revisions.ts](https://github.com/puppeteer/puppeteer/blob/main/src/revisions.ts). To find the corresponding Chromium commit and version number, search for the revision prefixed by an `r` in [OmahaProxy](https://omahaproxy.appspot.com/)'s "Find Releases" section.
- Look for the `versionsPerRelease` map in [versions.js](https://github.com/puppeteer/puppeteer/blob/main/versions.js) which contains mapping between Chromium and Puppeteer versions. Note: The file contains only Puppeteer versions where Chromium is updated. Not all Puppeteer versions are listed.
#### Q: Which Firefox version does Puppeteer use?
Since Firefox support is experimental, Puppeteer downloads the latest [Firefox Nightly](https://wiki.mozilla.org/Nightly) when the `PUPPETEER_PRODUCT` environment variable is set to `firefox`. That's also why the value of `firefox` in [revisions.ts](https://github.com/puppeteer/puppeteer/blob/main/src/revisions.ts) is `latest` -- Puppeteer isn't tied to a particular Firefox version.
To fetch Firefox Nightly as part of Puppeteer installation:
```bash
PUPPETEER_PRODUCT=firefox npm i puppeteer
# or "yarn add puppeteer"
```
#### Q: What’s considered a “Navigation”?
From Puppeteer’s standpoint, **“navigation” is anything that changes a page’s URL**.
Aside from regular navigation where the browser hits the network to fetch a new document from the web server, this includes [anchor navigations](https://www.w3.org/TR/html5/single-page.html#scroll-to-fragid) and [History API](https://developer.mozilla.org/en-US/docs/Web/API/History_API) usage.
With this definition of “navigation,” **Puppeteer works seamlessly with single-page applications.**
#### Q: What’s the difference between a “trusted" and "untrusted" input event?
In browsers, input events could be divided into two big groups: trusted vs. untrusted.
- **Trusted events**: events generated by users interacting with the page, e.g. using a mouse or keyboard.
- **Untrusted event**: events generated by Web APIs, e.g. `document.createEvent` or `element.click()` methods.
Websites can distinguish between these two groups:
- using an [`Event.isTrusted`](https://developer.mozilla.org/en-US/docs/Web/API/Event/isTrusted) event flag
- sniffing for accompanying events. For example, every trusted `'click'` event is preceded by `'mousedown'` and `'mouseup'` events.
For automation purposes it’s important to generate trusted events. **All input events generated with Puppeteer are trusted and fire proper accompanying events.** If, for some reason, one needs an untrusted event, it’s always possible to hop into a page context with `page.evaluate` and generate a fake event:
```js
await page.evaluate(() => {
document.querySelector('button[type=submit]').click();
});
```
#### Q: What features does Puppeteer not support?
You may find that Puppeteer does not behave as expected when controlling pages that incorporate audio and video. (For example, [video playback/screenshots is likely to fail](https://github.com/puppeteer/puppeteer/issues/291).) There are two reasons for this:
- Puppeteer is bundled with Chromium — not Chrome — and so by default, it inherits all of [Chromium's media-related limitations](https://www.chromium.org/audio-video). This means that Puppeteer does not support licensed formats such as AAC or H.264. (However, it is possible to force Puppeteer to use a separately-installed version Chrome instead of Chromium via the [`executablePath` option to `puppeteer.launch`](https://github.com/puppeteer/puppeteer/blob/v15.2.0/docs/api.md#puppeteerlaunchoptions). You should only use this configuration if you need an official release of Chrome that supports these media formats.)
- Since Puppeteer (in all configurations) controls a desktop version of Chromium/Chrome, features that are only supported by the mobile version of Chrome are not supported. This means that Puppeteer [does not support HTTP Live Streaming (HLS)](https://caniuse.com/#feat=http-live-streaming).
#### Q: I am having trouble installing / running Puppeteer in my test environment. Where should I look for help?
We have a [troubleshooting](https://github.com/puppeteer/puppeteer/blob/main/docs/troubleshooting.md) guide for various operating systems that lists the required dependencies.
#### Q: Chromium gets downloaded on every `npm ci` run. How can I cache the download?
The default download path is `node_modules/puppeteer/.local-chromium`. However, you can change that path with the `PUPPETEER_DOWNLOAD_PATH` environment variable.
Puppeteer uses that variable to resolve the Chromium executable location during launch, so you don’t need to specify `PUPPETEER_EXECUTABLE_PATH` as well.
For example, if you wish to keep the Chromium download in `~/.npm/chromium`:
```sh
export PUPPETEER_DOWNLOAD_PATH=~/.npm/chromium
npm ci
# by default the Chromium executable path is inferred
# from the download path
npm test
# a new run of npm ci will check for the existence of
# Chromium in ~/.npm/chromium
npm ci
```
#### Q: I have more questions! Where do I ask?
There are many ways to get help on Puppeteer:
- [bugtracker](https://github.com/puppeteer/puppeteer/issues)
- [Stack Overflow](https://stackoverflow.com/questions/tagged/puppeteer)
Make sure to search these channels before posting your question.
<!-- [END faq] -->
Our [FAQ](https://pptr.dev/faq) has migrated to [our site](https://pptr.dev/faq).