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Puppeteer API v1.0.0-rc

内容目录

概览

Puppeteer 是一个 Node 库，它提供了一系列高级 API 来使用 DevTools协议 控制 Chromium 或者 Chrome。

Puppeteer API 是分层并且镜像于浏览器的结构。在下面的图表上，褪色的实体当前没有在Puppeteer 中表现出来。

puppeteer overview

  • Puppeteer 使用 devtools 协议 与浏览器通信。
  • Browser 实例拥有多个页面。
  • Page 至少有一个框架: 主框架。 可能还有其他由 iframe 或 frame 标签创建的框架。
  • Frame 至少有一个可执行上下文 - 默认可执行上下文 - 其中框架的 JavaScript 被执行。框架可能有额外的与扩展相关联的执行上下文。

(图表资源: link)

环境变量

Puppeteer 会查找某些 环境变量 来帮助其操作。 这些变量既可以在环境中设置，也可以在 npm 配置 中设置。

  • HTTP_PROXY, HTTPS_PROXY, NO_PROXY - 定义用于下载和运行 Chromium 的 HTTP 代理设置。
  • PUPPETEER_SKIP_CHROMIUM_DOWNLOAD - 安装过程中不要下载捆绑的 Chromium。
  • PUPPETEER_DOWNLOAD_HOST - 覆盖用于下载 Chromium 的 URL 的主机部分

class: Puppeteer

Puppeteer module provides a method to launch a Chromium instance. The following is a typical example of using a Puppeteer to drive automation:

const puppeteer = require('puppeteer');

puppeteer.launch().then(async browser => {
  const page = await browser.newPage();
  await page.goto('https://www.google.com');
  // other actions...
  await browser.close();
});

puppeteer.connect(options)

This methods attaches Puppeteer to an existing Chromium instance.

puppeteer.defaultArgs()

  • returns: <Array<string>> The default flags that Chromium will be launched with.

puppeteer.executablePath()

puppeteer.launch([options])

  • options <Object> Set of configurable options to set on the browser. Can have the following fields:
    • ignoreHTTPSErrors <boolean> Whether to ignore HTTPS errors during navigation. Defaults to false.
    • headless <boolean> Whether to run browser in headless mode. Defaults to true unless the devtools option is true.
    • executablePath <string> Path to a Chromium or Chrome executable to run instead of bundled Chromium. If executablePath is a relative path, then it is resolved relative to current working directory.
    • slowMo <number> Slows down Puppeteer operations by the specified amount of milliseconds. Useful so that you can see what is going on.
    • args <Array<string>> Additional arguments to pass to the browser instance. List of Chromium flags can be found here.
    • ignoreDefaultArgs <boolean> Do not use puppeteer.defaultArgs(). Dangerous option; use with care. Defaults to false.
    • handleSIGINT <boolean> Close browser process on Ctrl-C. Defaults to true.
    • handleSIGTERM <boolean> Close browser process on SIGTERM. Defaults to true.
    • handleSIGHUP <boolean> Close browser process on SIGHUP. Defaults to true.
    • timeout <number> Maximum time in milliseconds to wait for the browser instance to start. Defaults to 30000 (30 seconds). Pass 0 to disable timeout.
    • dumpio <boolean> Whether to pipe browser process stdout and stderr into process.stdout and process.stderr. Defaults to false.
    • userDataDir <string> Path to a User Data Directory.
    • env <Object> Specify environment variables that will be visible to browser. Defaults to process.env.
    • devtools <boolean> Whether to auto-open DevTools panel for each tab. If this option is true, the headless option will be set false.
  • returns: <Promise<Browser>> Promise which resolves to browser instance.

The method launches a browser instance with given arguments. The browser will be closed when the parent node.js process is closed.

NOTE Puppeteer can also be used to control the Chrome browser, but it works best with the version of Chromium it is bundled with. There is no guarantee it will work with any other version. Use executablePath option with extreme caution. If Google Chrome (rather than Chromium) is preferred, a Chrome Canary or Dev Channel build is suggested.

In puppeteer.launch([options]) above, any mention of Chromium also applies to Chrome.

See this article for a description of the differences between Chromium and Chrome. This article describes some differences for Linux users.

class: Browser

A Browser is created when Puppeteer connects to a Chromium instance, either through puppeteer.launch or puppeteer.connect.

An example of using a Browser to create a Page:

const puppeteer = require('puppeteer');

puppeteer.launch().then(async browser => {
  const page = await browser.newPage();
  await page.goto('https://example.com');
  await browser.close();
});

An example of disconnecting from and reconnecting to a Browser:

const puppeteer = require('puppeteer');

puppeteer.launch().then(async browser => {
  // Store the endpoint to be able to reconnect to Chromium
  const browserWSEndpoint = browser.wsEndpoint();
  // Disconnect puppeteer from Chromium
  browser.disconnect();

  // Use the endpoint to reestablish a connection
  const browser2 = await puppeteer.connect({browserWSEndpoint});
  // Close Chromium
  await browser2.close();
});

event: 'disconnected'

Emitted when puppeteer gets disconnected from the Chromium instance. This might happen because one of the following:

  • Chromium is closed or crashed
  • browser.disconnect method was called

event: 'targetchanged'

Emitted when the url of a target changes.

event: 'targetcreated'

Emitted when a target is created, for example when a new page is opened by window.open or browser.newPage.

event: 'targetdestroyed'

Emitted when a target is destroyed, for example when a page is closed.

browser.close()

Closes Chromium and all of its pages (if any were opened). The browser object itself is considered disposed and cannot be used anymore.

browser.disconnect()

Disconnects Puppeteer from the browser, but leaves the Chromium process running. After calling disconnect, the browser object is considered disposed and cannot be used anymore.

browser.newPage()

browser.pages()

  • returns: <Promise<Array<Page>>> Promise which resolves to an array of all open pages.

browser.process()

  • returns: <?ChildProcess> Spawned browser process. Returns null if the browser instance was created with puppeteer.connect method.

browser.targets()

  • returns: <Array<Target>> An array of all active targets.

browser.userAgent()

  • returns: <Promise<string>> Promise which resolves to the browser's original user agent.

NOTE Pages can override browser user agent with page.setUserAgent

browser.version()

  • returns: <Promise<string>> For headless Chromium, this is similar to HeadlessChrome/61.0.3153.0. For non-headless, this is similar to Chrome/61.0.3153.0.

NOTE the format of browser.version() might change with future releases of Chromium.

browser.wsEndpoint()

  • returns: <string> Browser websocket url.

Browser websocket endpoint which can be used as an argument to puppeteer.connect. The format is ws://${host}:${port}/devtools/browser/<id>

You can find the webSocketDebuggerUrl from http://${host}:${port}/json/version. Learn more about the devtools protocol and the browser endpoint.

class: Page

Page provides methods to interact with a single tab in Chromium. One Browser instance might have multiple Page instances.

This example creates a page, navigates it to a URL, and then saves a screenshot:

const puppeteer = require('puppeteer');

puppeteer.launch().then(async browser => {
  const page = await browser.newPage();
  await page.goto('https://example.com');
  await page.screenshot({path: 'screenshot.png'});
  await browser.close();
});

The Page class emits various events (described below) which can be handled using any of Node's native EventEmitter methods, such as on or once.

This example logs a message for a single page load event:

page.once('load', () => console.log('Page loaded!'));

event: 'console'

Emitted when JavaScript within the page calls one of console API methods, e.g. console.log or console.dir. Also emitted if the page throws an error or a warning.

The arguments passed into console.log appear as arguments on the event handler.

An example of handling console event:

page.on('console', msg => {
  for (let i = 0; i < msg.args.length; ++i)
    console.log(`${i}: ${msg.args[i]}`);
});
page.evaluate(() => console.log('hello', 5, {foo: 'bar'}));

event: 'dialog'

Emitted when a JavaScript dialog appears, such as alert, prompt, confirm or beforeunload. Puppeteer can respond to the dialog via Dialog's accept or dismiss methods.

event: 'error'

Emitted when the page crashes.

NOTE error event has a special meaning in Node, see error events for details.

event: 'frameattached'

Emitted when a frame is attached.

event: 'framedetached'

Emitted when a frame is detached.

event: 'framenavigated'

Emitted when a frame is navigated to a new url.

event: 'load'

Emitted when the JavaScript load event is dispatched.

event: 'metrics'

  • <Object>
    • title <string> The title passed to console.timeStamp.
    • metrics <Object> Object containing metrics as key/value pairs. The values of metrics are of <number> type.

Emitted when the JavaScript code makes a call to console.timeStamp. For the list of metrics see page.metrics.

event: 'pageerror'

  • <string> The exception message

Emitted when an uncaught exception happens within the page.

event: 'request'

Emitted when a page issues a request. The request object is read-only. In order to intercept and mutate requests, see page.setRequestInterception.

event: 'requestfailed'

Emitted when a request fails, for example by timing out.

event: 'requestfinished'

Emitted when a request finishes successfully.

event: 'response'

Emitted when a response is received.

page.$(selector)

The method runs document.querySelector within the page. If no element matches the selector, the return value resolve to null.

Shortcut for page.mainFrame().$(selector).

page.$$(selector)

The method runs document.querySelectorAll within the page. If no elements match the selector, the return value resolve to [].

Shortcut for page.mainFrame().$$(selector).

page.$$eval(selector, pageFunction[, ...args])

This method runs document.querySelectorAll within the page and passes it as the first argument to pageFunction.

If pageFunction returns a Promise, then page.$$eval would wait for the promise to resolve and return its value.

Examples:

const divsCounts = await page.$$eval('div', divs => divs.length);

page.$eval(selector, pageFunction[, ...args])

This method runs document.querySelector within the page and passes it as the first argument to pageFunction. If there's no element matching selector, the method throws an error.

If pageFunction returns a Promise, then page.$eval would wait for the promise to resolve and return its value.

Examples:

const searchValue = await page.$eval('#search', el => el.value);
const preloadHref = await page.$eval('link[rel=preload]', el => el.href);
const html = await page.$eval('.main-container', e => e.outerHTML);

Shortcut for page.mainFrame().$eval(selector, pageFunction).

page.$x(expression)

The method evluates the XPath expression.

Shortcut for page.mainFrame().$x(expression)

page.addScriptTag(options)

  • options <Object>
    • url <string> Url of a script to be added.
    • path <string> Path to the JavaScript file to be injected into frame. If path is a relative path, then it is resolved relative to current working directory.
    • content <string> Raw JavaScript content to be injected into frame.
  • returns: <Promise<ElementHandle>> which resolves to the added tag when the script's onload fires or when the script content was injected into frame.

Adds a <script> tag into the page with the desired url or content.

Shortcut for page.mainFrame().addScriptTag(options).

page.addStyleTag(options)

  • options <Object>
    • url <string> Url of the <link> tag.
    • path <string> Path to the CSS file to be injected into frame. If path is a relative path, then it is resolved relative to current working directory.
    • content <string> Raw CSS content to be injected into frame.
  • returns: <Promise<ElementHandle>> which resolves to the added tag when the stylesheet's onload fires or when the CSS content was injected into frame.

Adds a <link rel="stylesheet"> tag into the page with the desired url or a <style type="text/css"> tag with the content.

Shortcut for page.mainFrame().addStyleTag(options).

page.authenticate(credentials)

Provide credentials for http authentication.

To disable authentication, pass null.

page.bringToFront()

Brings page to front (activates tab).

page.click(selector[, options])

  • selector <string> A selector to search for element to click. If there are multiple elements satisfying the selector, the first will be clicked.
  • options <Object>
    • button <string> left, right, or middle, defaults to left.
    • clickCount <number> defaults to 1. See UIEvent.detail.
    • delay <number> Time to wait between mousedown and mouseup in milliseconds. Defaults to 0.
  • returns: <Promise> Promise which resolves when the element matching selector is successfully clicked. The Promise will be rejected if there is no element matching selector.

This method fetches an element with selector, scrolls it into view if needed, and then uses page.mouse to click in the center of the element. If there's no element matching selector, the method throws an error.

page.close()

page.content()

Gets the full HTML contents of the page, including the doctype.

page.cookies(...urls)

If no URLs are specified, this method returns cookies for the current page URL. If URLs are specified, only cookies for those URLs are returned.

page.coverage

page.deleteCookie(...cookies)

page.emulate(options)

  • options <Object>
    • viewport <Object>
      • width <number> page width in pixels.
      • height <number> page height in pixels.
      • deviceScaleFactor <number> Specify device scale factor (can be thought of as dpr). Defaults to 1.
      • isMobile <boolean> Whether the meta viewport tag is taken into account. Defaults to false.
      • hasTouch<boolean> Specifies if viewport supports touch events. Defaults to false
      • isLandscape <boolean> Specifies if viewport is in landscape mode. Defaults to false.
    • userAgent <string>
  • returns: <Promise>

Emulates given device metrics and user agent. This method is a shortcut for calling two methods:

To aid emulation, puppeteer provides a list of device descriptors which can be obtained via the require('puppeteer/DeviceDescriptors') command. Below is an example of emulating an iPhone 6 in puppeteer:

const puppeteer = require('puppeteer');
const devices = require('puppeteer/DeviceDescriptors');
const iPhone = devices['iPhone 6'];

puppeteer.launch().then(async browser => {
  const page = await browser.newPage();
  await page.emulate(iPhone);
  await page.goto('https://www.google.com');
  // other actions...
  await browser.close();
});

List of all available devices is available in the source code: DeviceDescriptors.js.

page.emulateMedia(mediaType)

  • mediaType <?string> Changes the CSS media type of the page. The only allowed values are 'screen', 'print' and null. Passing null disables media emulation.
  • returns: <Promise>

page.evaluate(pageFunction, ...args)

If the function, passed to the page.evaluate, returns a Promise, then page.evaluate would wait for the promise to resolve and return its value.

If the function passed into page.evaluate returns a non-Serializable value, then page.evaluate resolves to undefined.

const result = await page.evaluate(() => {
  return Promise.resolve(8 * 7);
});
console.log(result); // prints "56"

A string can also be passed in instead of a function.

console.log(await page.evaluate('1 + 2')); // prints "3"

ElementHandle instances can be passed as arguments to the page.evaluate:

const bodyHandle = await page.$('body');
const html = await page.evaluate(body => body.innerHTML, bodyHandle);
await bodyHandle.dispose();

Shortcut for page.mainFrame().evaluate(pageFunction, ...args).

page.evaluateHandle(pageFunction, ...args)

If the function, passed to the page.evaluateHandle, returns a Promise, then page.evaluateHandle would wait for the promise to resolve and return its value.

const aWindowHandle = await page.evaluateHandle(() => Promise.resolve(window));
aWindowHandle; // Handle for the window object.

A string can also be passed in instead of a function.

const aHandle = await page.evaluateHandle('document'); // Handle for the 'document'.

JSHandle instances can be passed as arguments to the page.evaluateHandle:

const aHandle = await page.evaluateHandle(() => document.body);
const resultHandle = await page.evaluateHandle(body => body.innerHTML, aHandle);
console.log(await resultHandle.jsonValue());
await resultHandle.dispose();

Shortcut for page.mainFrame().executionContext().evaluateHandle(pageFunction, ...args).

page.evaluateOnNewDocument(pageFunction, ...args)

Adds a function which would be invoked in one of the following scenarios:

  • whenever the page is navigated
  • whenever the child frame is attached or navigated. In this case, the function is invoked in the context of the newly attached frame

The function is invoked after the document was created but before any of its scripts were run. This is useful to amend JavaScript environment, e.g. to seed Math.random.

An example of overriding the navigator.languages property before the page loads:

// preload.js

// overwrite the `languages` property to use a custom getter
Object.defineProperty(navigator, "languages", {
  get: function() {
    return ["en-US", "en", "bn"];
  };
});

// In your puppeteer script, assuming the preload.js file is in same folder of our script
const preloadFile = fs.readFileSync('./preload.js', 'utf8');
await page.evaluateOnNewDocument(preloadFile);

page.exposeFunction(name, puppeteerFunction)

  • name <string> Name of the function on the window object
  • puppeteerFunction <function> Callback function which will be called in Puppeteer's context.
  • returns: <Promise>

The method adds a function called name on the page's window object. When called, the function executes puppeteerFunction in node.js and returns a Promise which resolves to the return value of puppeteerFunction.

If the puppeteerFunction returns a Promise, it will be awaited.

NOTE Functions installed via page.exposeFunction survive navigations.

An example of adding an md5 function into the page:

const puppeteer = require('puppeteer');
const crypto = require('crypto');

puppeteer.launch().then(async browser => {
  const page = await browser.newPage();
  page.on('console', msg => console.log(msg.text));
  await page.exposeFunction('md5', text =>
    crypto.createHash('md5').update(text).digest('hex')
  );
  await page.evaluate(async () => {
    // use window.md5 to compute hashes
    const myString = 'PUPPETEER';
    const myHash = await window.md5(myString);
    console.log(`md5 of ${myString} is ${myHash}`);
  });
  await browser.close();
});

An example of adding a window.readfile function into the page:

const puppeteer = require('puppeteer');
const fs = require('fs');

puppeteer.launch().then(async browser => {
  const page = await browser.newPage();
  page.on('console', msg => console.log(msg.text));
  await page.exposeFunction('readfile', async filePath => {
    return new Promise((resolve, reject) => {
      fs.readFile(filePath, 'utf8', (err, text) => {
        if (err)
          reject(err);
        else
          resolve(text);
      });
    });
  });
  await page.evaluate(async () => {
    // use window.readfile to read contents of a file
    const content = await window.readfile('/etc/hosts');
    console.log(content);
  });
  await browser.close();
});

page.focus(selector)

  • selector <string> A selector of an element to focus. If there are multiple elements satisfying the selector, the first will be focused.
  • returns: <Promise> Promise which resolves when the element matching selector is successfully focused. The promise will be rejected if there is no element matching selector.

This method fetches an element with selector and focuses it. If there's no element matching selector, the method throws an error.

page.frames()

  • returns: <Array<Frame>> An array of all frames attached to the page.

page.goBack(options)

  • options <Object> Navigation parameters which might have the following properties:
    • timeout <number> Maximum navigation time in milliseconds, defaults to 30 seconds, pass 0 to disable timeout.
    • waitUntil <string|Array<string>> When to consider navigation succeeded, defaults to load. Given an array of event strings, navigation is considered to be successful after all events have been fired. Events can be either:
      • load - consider navigation to be finished when the load event is fired.
      • domcontentloaded - consider navigation to be finished when the DOMContentLoaded event is fired.
      • networkidle0 - consider navigation to be finished when there are no more than 0 network connections for at least 500 ms.
      • networkidle2 - consider navigation to be finished when there are no more than 2 network connections for at least 500 ms.
  • returns: <Promise<?Response>> Promise which resolves to the main resource response. In case of multiple redirects, the navigation will resolve with the response of the last redirect. If can not go back, resolves to null.

Navigate to the previous page in history.

page.goForward(options)

  • options <Object> Navigation parameters which might have the following properties:
    • timeout <number> Maximum navigation time in milliseconds, defaults to 30 seconds, pass 0 to disable timeout.
    • waitUntil <string|Array<string>> When to consider navigation succeeded, defaults to load. Given an array of event strings, navigation is considered to be successful after all events have been fired. Events can be either:
      • load - consider navigation to be finished when the load event is fired.
      • domcontentloaded - consider navigation to be finished when the DOMContentLoaded event is fired.
      • networkidle0 - consider navigation to be finished when there are no more than 0 network connections for at least 500 ms.
      • networkidle2 - consider navigation to be finished when there are no more than 2 network connections for at least 500 ms.
  • returns: <Promise<?Response>> Promise which resolves to the main resource response. In case of multiple redirects, the navigation will resolve with the response of the last redirect. If can not go back, resolves to null.

Navigate to the next page in history.

page.goto(url, options)

  • url <string> URL to navigate page to. The url should include scheme, e.g. https://.
  • options <Object> Navigation parameters which might have the following properties:
    • timeout <number> Maximum navigation time in milliseconds, defaults to 30 seconds, pass 0 to disable timeout.
    • waitUntil <string|Array<string>> When to consider navigation succeeded, defaults to load. Given an array of event strings, navigation is considered to be successful after all events have been fired. Events can be either:
      • load - consider navigation to be finished when the load event is fired.
      • domcontentloaded - consider navigation to be finished when the DOMContentLoaded event is fired.
      • networkidle0 - consider navigation to be finished when there are no more than 0 network connections for at least 500 ms.
      • networkidle2 - consider navigation to be finished when there are no more than 2 network connections for at least 500 ms.
  • returns: <Promise<?Response>> Promise which resolves to the main resource response. In case of multiple redirects, the navigation will resolve with the response of the last redirect.

The page.goto will throw an error if:

  • there's an SSL error (e.g. in case of self-signed certificates).
  • target URL is invalid.
  • the timeout is exceeded during navigation.
  • the main resource failed to load.

NOTE page.goto either throw or return a main resource response. The only exception is navigation to about:blank, which would succeed and return null.

NOTE Headless mode doesn't support navigating to a PDF document. See the upstream issue.

page.hover(selector)

  • selector <string> A selector to search for element to hover. If there are multiple elements satisfying the selector, the first will be hovered.
  • returns: <Promise> Promise which resolves when the element matching selector is successfully hovered. Promise gets rejected if there's no element matching selector.

This method fetches an element with selector, scrolls it into view if needed, and then uses page.mouse to hover over the center of the element. If there's no element matching selector, the method throws an error.

page.keyboard

page.mainFrame()

  • returns: <Frame> returns page's main frame.

Page is guaranteed to have a main frame which persists during navigations.

page.metrics()

  • returns: <Promise<Object>> Object containing metrics as key/value pairs.
    • Timestamp <number> The timestamp when the metrics sample was taken.
    • Documents <number> Number of documents in the page.
    • Frames <number> Number of frames in the page.
    • JSEventListeners <number> Number of events in the page.
    • Nodes <number> Number of DOM nodes in the page.
    • LayoutCount <number> Total number of full or partial page layout.
    • RecalcStyleCount <number> Total number of page style recalculations.
    • LayoutDuration <number> Combined durations of all page layouts.
    • RecalcStyleDuration <number> Combined duration of all page style recalculations.
    • ScriptDuration <number> Combined duration of JavaScript execution.
    • TaskDuration <number> Combined duration of all tasks performed by the browser.
    • JSHeapUsedSize <number> Used JavaScript heap size.
    • JSHeapTotalSize <number> Total JavaScript heap size.

NOTE All timestamps are in monotonic time: monotonically increasing time in seconds since an arbitrary point in the past.

page.mouse

page.pdf(options)

  • options <Object> Options object which might have the following properties:
    • path <string> The file path to save the PDF to. If path is a relative path, then it is resolved relative to current working directory. If no path is provided, the PDF won't be saved to the disk.
    • scale <number> Scale of the webpage rendering. Defaults to 1.
    • displayHeaderFooter <boolean> Display header and footer. Defaults to false.
    • headerTemplate <string> HTML template for the print header. Should be valid HTML markup with following classes used to inject printing values into them:
      • date formatted print date
      • title document title
      • url document location
      • pageNumber current page number
      • totalPages total pages in the document
    • footerTemplate <string> HTML template for the print footer. Should use the same format as the headerTemplate.
    • printBackground <boolean> Print background graphics. Defaults to false.
    • landscape <boolean> Paper orientation. Defaults to false.
    • pageRanges <string> Paper ranges to print, e.g., '1-5, 8, 11-13'. Defaults to the empty string, which means print all pages.
    • format <string> Paper format. If set, takes priority over width or height options. Defaults to 'Letter'.
    • width <string> Paper width, accepts values labeled with units.
    • height <string> Paper height, accepts values labeled with units.
    • margin <Object> Paper margins, defaults to none.
      • top <string> Top margin, accepts values labeled with units.
      • right <string> Right margin, accepts values labeled with units.
      • bottom <string> Bottom margin, accepts values labeled with units.
      • left <string> Left margin, accepts values labeled with units.
  • returns: <Promise<Buffer>> Promise which resolves with PDF buffer.

NOTE Generating a pdf is currently only supported in Chrome headless.

page.pdf() generates a pdf of the page with print css media. To generate a pdf with screen media, call page.emulateMedia('screen') before calling page.pdf():

// Generates a PDF with 'screen' media type.
await page.emulateMedia('screen');
await page.pdf({path: 'page.pdf'});

The width, height, and margin options accept values labeled with units. Unlabeled values are treated as pixels.

A few examples:

  • page.pdf({width: 100}) - prints with width set to 100 pixels
  • page.pdf({width: '100px'}) - prints with width set to 100 pixels
  • page.pdf({width: '10cm'}) - prints with width set to 10 centimeters.

All possible units are:

  • px - pixel
  • in - inch
  • cm - centimeter
  • mm - millimeter

The format options are:

  • Letter: 8.5in x 11in
  • Legal: 8.5in x 14in
  • Tabloid: 11in x 17in
  • Ledger: 17in x 11in
  • A0: 33.1in x 46.8in
  • A1: 23.4in x 33.1in
  • A2: 16.5in x 23.4in
  • A3: 11.7in x 16.5in
  • A4: 8.27in x 11.7in
  • A5: 5.83in x 8.27in
  • A6: 4.13in x 5.83in

page.queryObjects(prototypeHandle)

  • prototypeHandle <JSHandle> A handle to the object prototype.
  • returns: <Promise<JSHandle>> Promise which resolves to a handle to an array of objects with this prototype.

The method iterates JavaScript heap and finds all the objects with the given prototype.

// Create a Map object
await page.evaluate(() => window.map = new Map());
// Get a handle to the Map object prototype
const mapPrototype = await page.evaluateHandle(() => Map.prototype);
// Query all map instances into an array
const mapInstances = await page.queryObjects(mapPrototype);
// Count amount of map objects in heap
const count = await page.evaluate(maps => maps.length, mapInstances);
await mapInstances.dispose();
await mapPrototype.dispose();

Shortcut for page.mainFrame().executionContext().queryObjects(prototypeHandle).

page.reload(options)

  • options <Object> Navigation parameters which might have the following properties:
    • timeout <number> Maximum navigation time in milliseconds, defaults to 30 seconds, pass 0 to disable timeout.
    • waitUntil <string|Array<string>> When to consider navigation succeeded, defaults to load. Given an array of event strings, navigation is considered to be successful after all events have been fired. Events can be either:
      • load - consider navigation to be finished when the load event is fired.
      • domcontentloaded - consider navigation to be finished when the DOMContentLoaded event is fired.
      • networkidle0 - consider navigation to be finished when there are no more than 0 network connections for at least 500 ms.
      • networkidle2 - consider navigation to be finished when there are no more than 2 network connections for at least 500 ms.
  • returns: <Promise<Response>> Promise which resolves to the main resource response. In case of multiple redirects, the navigation will resolve with the response of the last redirect.

page.screenshot([options])

  • options <Object> Options object which might have the following properties:
    • path <string> The file path to save the image to. The screenshot type will be inferred from file extension. If path is a relative path, then it is resolved relative to current working directory. If no path is provided, the image won't be saved to the disk.
    • type <string> Specify screenshot type, can be either jpeg or png. Defaults to 'png'.
    • quality <number> The quality of the image, between 0-100. Not applicable to png images.
    • fullPage <boolean> When true, takes a screenshot of the full scrollable page. Defaults to false.
    • clip <Object> An object which specifies clipping region of the page. Should have the following fields:
      • x <number> x-coordinate of top-left corner of clip area
      • y <number> y-coordinate of top-left corner of clip area
      • width <number> width of clipping area
      • height <number> height of clipping area
    • omitBackground <boolean> Hides default white background and allows capturing screenshots with transparency. Defaults to false.
  • returns: <Promise<Buffer>> Promise which resolves to buffer with captured screenshot

page.select(selector, ...values)

  • selector <string> A selector to query page for
  • ...values <...string> Values of options to select. If the <select> has the multiple attribute, all values are considered, otherwise only the first one is taken into account.
  • returns: <Promise<Array<string>>> Returns an array of option values that have been successfully selected.

Triggers a change and input event once all the provided options have been selected. If there's no <select> element matching selector, the method throws an error.

page.select('select#colors', 'blue'); // single selection
page.select('select#colors', 'red', 'green', 'blue'); // multiple selections

Shortcut for page.mainFrame.select()

page.setContent(html)

  • html <string> HTML markup to assign to the page.
  • returns: <Promise>

page.setCookie(...cookies)

page.setExtraHTTPHeaders(headers)

  • headers <Object> An object containing additional http headers to be sent with every request. All header values must be strings.
  • returns: <Promise>

The extra HTTP headers will be sent with every request the page initiates.

NOTE page.setExtraHTTPHeaders does not guarantee the order of headers in the outgoing requests.

page.setJavaScriptEnabled(enabled)

  • enabled <boolean> Whether or not to enable JavaScript on the page.
  • returns: <Promise>

NOTE changing this value won't affect scripts that have already been run. It will take full effect on the next navigation.

page.setOfflineMode(enabled)

  • enabled <boolean> When true, enables offline mode for the page.
  • returns: <Promise>

page.setRequestInterception(value)

  • value <boolean> Whether to enable request interception.
  • returns: <Promise>

Activating request interception enables request.abort, request.continue and request.respond methods.

An example of a naïve request interceptor that aborts all image requests:

const puppeteer = require('puppeteer');

puppeteer.launch().then(async browser => {
  const page = await browser.newPage();
  await page.setRequestInterception(true);
  page.on('request', interceptedRequest => {
    if (interceptedRequest.url.endsWith('.png') || interceptedRequest.url.endsWith('.jpg'))
      interceptedRequest.abort();
    else
      interceptedRequest.continue();
  });
  await page.goto('https://example.com');
  await browser.close();
});

NOTE Enabling request interception disables page caching.

page.setUserAgent(userAgent)

  • userAgent <string> Specific user agent to use in this page
  • returns: <Promise> Promise which resolves when the user agent is set.

page.setViewport(viewport)

  • viewport <Object>
    • width <number> page width in pixels.
    • height <number> page height in pixels.
    • deviceScaleFactor <number> Specify device scale factor (can be thought of as dpr). Defaults to 1.
    • isMobile <boolean> Whether the meta viewport tag is taken into account. Defaults to false.
    • hasTouch<boolean> Specifies if viewport supports touch events. Defaults to false
    • isLandscape <boolean> Specifies if viewport is in landscape mode. Defaults to false.
  • returns: <Promise>

NOTE in certain cases, setting viewport will reload the page in order to set the isMobile or hasTouch properties.

In the case of multiple pages in a single browser, each page can have its own viewport size.

page.tap(selector)

  • selector <string> A selector to search for element to tap. If there are multiple elements satisfying the selector, the first will be tapped.
  • returns: <Promise>

This method fetches an element with selector, scrolls it into view if needed, and then uses page.touchscreen to tap in the center of the element. If there's no element matching selector, the method throws an error.

page.title()

Shortcut for page.mainFrame().title().

page.touchscreen

page.tracing

page.type(selector, text[, options])

  • selector <string> A selector of an element to type into. If there are multiple elements satisfying the selector, the first will be used.
  • text <string> A text to type into a focused element.
  • options <Object>
    • delay <number> Time to wait between key presses in milliseconds. Defaults to 0.
  • returns: <Promise>

Sends a keydown, keypress/input, and keyup event for each character in the text.

To press a special key, like Control or ArrowDown, use keyboard.press.

page.type('#mytextarea', 'Hello'); // Types instantly
page.type('#mytextarea', 'World', {delay: 100}); // Types slower, like a user

page.url()

This is a shortcut for page.mainFrame().url()

page.viewport()

  • returns: <Object>
    • width <number> page width in pixels.
    • height <number> page height in pixels.
    • deviceScaleFactor <number> Specify device scale factor (can be though of as dpr). Defaults to 1.
    • isMobile <boolean> Whether the meta viewport tag is taken into account. Defaults to false.
    • hasTouch<boolean> Specifies if viewport supports touch events. Defaults to false
    • isLandscape <boolean> Specifies if viewport is in landscape mode. Defaults to false.

page.waitFor(selectorOrFunctionOrTimeout[, options[, ...args]])

This method behaves differently with respect to the type of the first parameter:

  • if selectorOrFunctionOrTimeout is a string, then the first argument is treated as a selector to wait for and the method is a shortcut for page.waitForSelector
  • if selectorOrFunctionOrTimeout is a function, then the first argument is treated as a predicate to wait for and the method is a shortcut for page.waitForFunction().
  • if selectorOrFunctionOrTimeout is a number, then the first argument is treated as a timeout in milliseconds and the method returns a promise which resolves after the timeout
  • otherwise, an exception is thrown

Shortcut for page.mainFrame().waitFor(selectorOrFunctionOrTimeout[, options[, ...args]]).

page.waitForFunction(pageFunction[, options[, ...args]])

  • pageFunction <function|string> Function to be evaluated in browser context
  • options <Object> Optional waiting parameters
    • polling <string|number> An interval at which the pageFunction is executed, defaults to raf. If polling is a number, then it is treated as an interval in milliseconds at which the function would be executed. If polling is a string, then it can be one of the following values:
      • raf - to constantly execute pageFunction in requestAnimationFrame callback. This is the tightest polling mode which is suitable to observe styling changes.
      • mutation - to execute pageFunction on every DOM mutation.
    • timeout <number> maximum time to wait for in milliseconds. Defaults to 30000 (30 seconds).
  • ...args <...Serializable|JSHandle> Arguments to pass to pageFunction
  • returns: <Promise<JSHandle>> Promise which resolves when the pageFunction returns a truthy value. It resolves to a JSHandle of the truthy value.

The waitForFunction can be used to observe viewport size change:

const puppeteer = require('puppeteer');

puppeteer.launch().then(async browser => {
  const page = await browser.newPage();
  const watchDog = page.waitForFunction('window.innerWidth < 100');
  page.setViewport({width: 50, height: 50});
  await watchDog;
  await browser.close();
});

Shortcut for page.mainFrame().waitForFunction(pageFunction[, options[, ...args]]).

page.waitForNavigation(options)

  • options <Object> Navigation parameters which might have the following properties:
    • timeout <number> Maximum navigation time in milliseconds, defaults to 30 seconds, pass 0 to disable timeout.
    • waitUntil <string|Array<string>> When to consider navigation succeeded, defaults to load. Given an array of event strings, navigation is considered to be successful after all events have been fired. Events can be either:
      • load - consider navigation to be finished when the load event is fired.
      • domcontentloaded - consider navigation to be finished when the DOMContentLoaded event is fired.
      • networkidle0 - consider navigation to be finished when there are no more than 0 network connections for at least 500 ms.
      • networkidle2 - consider navigation to be finished when there are no more than 2 network connections for at least 500 ms.
  • returns: <Promise<Response>> Promise which resolves to the main resource response. In case of multiple redirects, the navigation will resolve with the response of the last redirect.

page.waitForSelector(selector[, options])

  • selector <string> A selector of an element to wait for,
  • options <Object> Optional waiting parameters
    • visible <boolean> wait for element to be present in DOM and to be visible, i.e. to not have display: none or visibility: hidden CSS properties. Defaults to false.
    • hidden <boolean> wait for element to not be found in the DOM or to be hidden, i.e. have display: none or visibility: hidden CSS properties. Defaults to false.
    • timeout <number> maximum time to wait for in milliseconds. Defaults to 30000 (30 seconds).
  • returns: <Promise<ElementHandle>> Promise which resolves when element specified by selector string is added to DOM.

Wait for the selector to appear in page. If at the moment of calling the method the selector already exists, the method will return immediately. If the selector doesn't appear after the timeout milliseconds of waiting, the function will throw.

This method works across navigations:

const puppeteer = require('puppeteer');

puppeteer.launch().then(async browser => {
  const page = await browser.newPage();
  let currentURL;
  page
    .waitForSelector('img')
    .then(() => console.log('First URL with image: ' + currentURL));
  for (currentURL of ['https://example.com', 'https://google.com', 'https://bbc.com'])
    await page.goto(currentURL);
  await browser.close();
});

Shortcut for page.mainFrame().waitForSelector(selector[, options]).

class: Keyboard

Keyboard provides an api for managing a virtual keyboard. The high level api is keyboard.type, which takes raw characters and generates proper keydown, keypress/input, and keyup events on your page.

For finer control, you can use keyboard.down, keyboard.up, and keyboard.sendCharacter to manually fire events as if they were generated from a real keyboard.

An example of holding down Shift in order to select and delete some text:

await page.keyboard.type('Hello World!');
await page.keyboard.press('ArrowLeft');

await page.keyboard.down('Shift');
for (let i = 0; i < ' World'.length; i++)
  await page.keyboard.press('ArrowLeft');
await page.keyboard.up('Shift');

await page.keyboard.press('Backspace');
// Result text will end up saying 'Hello!'

An example of pressing A

await page.keyboard.down('Shift');
await page.keyboard.press('KeyA');
await page.keyboard.up('Shift');

NOTE On MacOS, keyboard shortcuts like ⌘ A -> Select All do not work. See #1313

keyboard.down(key[, options])

  • key <string> Name of key to press, such as ArrowLeft. See USKeyboardLayout for a list of all key names.
  • options <Object>
    • text <string> If specified, generates an input event with this text.
  • returns: <Promise>

Dispatches a keydown event.

If key is a single character and no modifier keys besides Shift are being held down, a keypress/input event will also generated. The text option can be specified to force an input event to be generated.

If key is a modifier key, Shift, Meta, Control, or Alt, subsequent key presses will be sent with that modifier active. To release the modifier key, use keyboard.up.

After the key is pressed once, subsequent calls to keyboard.down will have repeat set to true. To release the key, use keyboard.up.

NOTE Modifier keys DO influence keyboard.down. Holding down Shift will type the text in upper case.

keyboard.press(key[, options])

  • key <string> Name of key to press, such as ArrowLeft. See USKeyboardLayout for a list of all key names.
  • options <Object>
    • text <string> If specified, generates an input event with this text.
    • delay <number> Time to wait between keydown and keyup in milliseconds. Defaults to 0.
  • returns: <Promise>

If key is a single character and no modifier keys besides Shift are being held down, a keypress/input event will also generated. The text option can be specified to force an input event to be generated.

NOTE Modifier keys DO effect elementHandle.press. Holding down Shift will type the text in upper case.

Shortcut for keyboard.down and keyboard.up.

keyboard.sendCharacter(char)

  • char <string> Character to send into the page.
  • returns: <Promise>

Dispatches a keypress and input event. This does not send a keydown or keyup event.

page.keyboard.sendCharacter('嗨');

NOTE Modifier keys DO NOT effect keyboard.sendCharacter. Holding down Shift will not type the text in upper case.

keyboard.type(text, options)

  • text <string> A text to type into a focused element.
  • options <Object>
    • delay <number> Time to wait between key presses in milliseconds. Defaults to 0.
  • returns: <Promise>

Sends a keydown, keypress/input, and keyup event for each character in the text.

To press a special key, like Control or ArrowDown, use keyboard.press.

page.keyboard.type('Hello'); // Types instantly
page.keyboard.type('World', {delay: 100}); // Types slower, like a user

NOTE Modifier keys DO NOT effect keyboard.type. Holding down Shift will not type the text in upper case.

keyboard.up(key)

Dispatches a keyup event.

class: Mouse

mouse.click(x, y, [options])

Shortcut for mouse.move, mouse.down and mouse.up.

mouse.down([options])

Dispatches a mousedown event.

mouse.move(x, y, [options])

Dispatches a mousemove event.

mouse.up([options])

Dispatches a mouseup event.

class: Touchscreen

touchscreen.tap(x, y)

Dispatches a touchstart and touchend event.

class: Tracing

You can use tracing.start and tracing.stop to create a trace file which can be opened in Chrome DevTools or timeline viewer.

await page.tracing.start({path: 'trace.json'});
await page.goto('https://www.google.com');
await page.tracing.stop();

tracing.start(options)

  • options <Object>
    • path <string> A path to write the trace file to. required
    • screenshots <boolean> captures screenshots in the trace.
    • categories <Array<string>> specify custom categories to use instead of default.
  • returns: <Promise>

Only one trace can be active at a time per browser.

tracing.stop()

class: Dialog

Dialog objects are dispatched by page via the 'dialog' event.

An example of using Dialog class:

const puppeteer = require('puppeteer');

puppeteer.launch().then(async browser => {
  const page = await browser.newPage();
  page.on('dialog', async dialog => {
    console.log(dialog.message());
    await dialog.dismiss();
    await browser.close();
  });
  page.evaluate(() => alert('1'));
});

dialog.accept([promptText])

  • promptText <string> A text to enter in prompt. Does not cause any effects if the dialog's type is not prompt.
  • returns: <Promise> Promise which resolves when the dialog has been accepted.

dialog.defaultValue()

  • returns: <string> If dialog is prompt, returns default prompt value. Otherwise, returns empty string.

dialog.dismiss()

  • returns: <Promise> Promise which resolves when the dialog has been dismissed.

dialog.message()

  • returns: <string> A message displayed in the dialog.

dialog.type()

  • returns: <string> Dialog's type, can be one of alert, beforeunload, confirm or prompt.

class: ConsoleMessage

ConsoleMessage objects are dispatched by page via the 'console' event.

consoleMessage.args()

consoleMessage.text()

consoleMessage.type()

One of the following values: 'log', 'debug', 'info', 'error', 'warning', 'dir', 'dirxml', 'table', 'trace', 'clear', 'startGroup', 'startGroupCollapsed', 'endGroup', 'assert', 'profile', 'profileEnd', 'count', 'timeEnd'.

class: Frame

At every point of time, page exposes its current frame tree via the page.mainFrame() and frame.childFrames() methods.

Frame object's lifecycle is controlled by three events, dispatched on the page object:

  • 'frameattached' - fired when the frame gets attached to the page. A Frame can be attached to the page only once.
  • 'framenavigated' - fired when the frame commits navigation to a different URL.
  • 'framedetached' - fired when the frame gets detached from the page. A Frame can be detached from the page only once.

An example of dumping frame tree:

const puppeteer = require('puppeteer');

puppeteer.launch().then(async browser => {
  const page = await browser.newPage();
  await page.goto('https://www.google.com/chrome/browser/canary.html');
  dumpFrameTree(page.mainFrame(), '');
  await browser.close();

  function dumpFrameTree(frame, indent) {
    console.log(indent + frame.url());
    for (let child of frame.childFrames())
      dumpFrameTree(child, indent + '  ');
  }
});

frame.$(selector)

  • selector <string> Selector to query page for
  • returns: <Promise<?ElementHandle>> Promise which resolves to ElementHandle pointing to the frame element.

The method queries frame for the selector. If there's no such element within the frame, the method will resolve to null.

frame.$$(selector)

  • selector <string> Selector to query page for
  • returns: <Promise<Array<ElementHandle>>> Promise which resolves to ElementHandles pointing to the frame elements.

The method runs document.querySelectorAll within the frame. If no elements match the selector, the return value resolve to [].

frame.$$eval(selector, pageFunction[, ...args])

This method runs document.querySelectorAll within the frame and passes it as the first argument to pageFunction.

If pageFunction returns a Promise, then frame.$$eval would wait for the promise to resolve and return its value.

Examples:

const divsCounts = await frame.$$eval('div', divs => divs.length);

frame.$eval(selector, pageFunction[, ...args])

This method runs document.querySelector within the frame and passes it as the first argument to pageFunction. If there's no element matching selector, the method throws an error.

If pageFunction returns a Promise, then frame.$eval would wait for the promise to resolve and return its value.

Examples:

const searchValue = await frame.$eval('#search', el => el.value);
const preloadHref = await frame.$eval('link[rel=preload]', el => el.href);
const html = await frame.$eval('.main-container', e => e.outerHTML);

frame.$x(expression)

The method evluates the XPath expression.

frame.addScriptTag(options)

  • options <Object>
    • url <string> Url of a script to be added.
    • path <string> Path to the JavaScript file to be injected into frame. If path is a relative path, then it is resolved relative to current working directory.
    • content <string> Raw JavaScript content to be injected into frame.
  • returns: <Promise<ElementHandle>> which resolves to the added tag when the script's onload fires or when the script content was injected into frame.

Adds a <script> tag into the page with the desired url or content.

frame.addStyleTag(options)

  • options <Object>
    • url <string> Url of the <link> tag.
    • path <string> Path to the CSS file to be injected into frame. If path is a relative path, then it is resolved relative to current working directory.
    • content <string> Raw CSS content to be injected into frame.
  • returns: <Promise<ElementHandle>> which resolves to the added tag when the stylesheet's onload fires or when the CSS content was injected into frame.

Adds a <link rel="stylesheet"> tag into the page with the desired url or a <style type="text/css"> tag with the content.

frame.childFrames()

frame.content()

Gets the full HTML contents of the frame, including the doctype.

frame.evaluate(pageFunction, ...args)

If the function, passed to the frame.evaluate, returns a Promise, then frame.evaluate would wait for the promise to resolve and return its value.

If the function passed into frame.evaluate returns a non-Serializable value, then frame.evaluate resolves to undefined.

const result = await frame.evaluate(() => {
  return Promise.resolve(8 * 7);
});
console.log(result); // prints "56"

A string can also be passed in instead of a function.

console.log(await frame.evaluate('1 + 2')); // prints "3"

ElementHandle instances can be passed as arguments to the frame.evaluate:

const bodyHandle = await frame.$('body');
const html = await frame.evaluate(body => body.innerHTML, bodyHandle);
await bodyHandle.dispose();

frame.executionContext()

frame.isDetached()

Returns true if the frame has been detached, or false otherwise.

frame.name()

Returns frame's name attribute as specified in the tag.

If the name is empty, returns the id attribute instead.

NOTE This value is calculated once when the frame is created, and will not update if the attribute is changed later.

frame.parentFrame()

  • returns: <?Frame> Returns parent frame, if any. Detached frames and main frames return null.

frame.select(selector, ...values)

  • selector <string> A selector to query frame for
  • ...values <...string> Values of options to select. If the <select> has the multiple attribute, all values are considered, otherwise only the first one is taken into account.
  • returns: <Promise<Array<string>>> Returns an array of option values that have been successfully selected.

Triggers a change and input event once all the provided options have been selected. If there's no <select> element matching selector, the method throws an error.

frame.select('select#colors', 'blue'); // single selection
frame.select('select#colors', 'red', 'green', 'blue'); // multiple selections

frame.setContent(html)

  • html <string> HTML markup to assign to the page.
  • returns: <Promise>

frame.title()

frame.url()

Returns frame's url.

frame.waitFor(selectorOrFunctionOrTimeout[, options[, ...args]])

This method behaves differently with respect to the type of the first parameter:

  • if selectorOrFunctionOrTimeout is a string, then the first argument is treated as a selector to wait for and the method is a shortcut for frame.waitForSelector
  • if selectorOrFunctionOrTimeout is a function, then the first argument is treated as a predicate to wait for and the method is a shortcut for frame.waitForFunction().
  • if selectorOrFunctionOrTimeout is a number, then the first argument is treated as a timeout in milliseconds and the method returns a promise which resolves after the timeout
  • otherwise, an exception is thrown

frame.waitForFunction(pageFunction[, options[, ...args]])

  • pageFunction <function|string> Function to be evaluated in browser context
  • options <Object> Optional waiting parameters
    • polling <string|number> An interval at which the pageFunction is executed, defaults to raf. If polling is a number, then it is treated as an interval in milliseconds at which the function would be executed. If polling is a string, then it can be one of the following values:
      • raf - to constantly execute pageFunction in requestAnimationFrame callback. This is the tightest polling mode which is suitable to observe styling changes.
      • mutation - to execute pageFunction on every DOM mutation.
    • timeout <number> maximum time to wait for in milliseconds. Defaults to 30000 (30 seconds).
  • ...args <...Serializable|JSHandle> Arguments to pass to pageFunction
  • returns: <Promise<JSHandle>> Promise which resolves when the pageFunction returns a truthy value. It resolves to a JSHandle of the truthy value.

The waitForFunction can be used to observe viewport size change:

const puppeteer = require('puppeteer');

puppeteer.launch().then(async browser => {
  const page = await browser.newPage();
  const watchDog = page.mainFrame().waitForFunction('window.innerWidth < 100');
  page.setViewport({width: 50, height: 50});
  await watchDog;
  await browser.close();
});

frame.waitForSelector(selector[, options])

  • selector <string> A selector of an element to wait for,
  • options <Object> Optional waiting parameters
    • visible <boolean> wait for element to be present in DOM and to be visible, i.e. to not have display: none or visibility: hidden CSS properties. Defaults to false.
    • hidden <boolean> wait for element to not be found in the DOM or to be hidden, i.e. have display: none or visibility: hidden CSS properties. Defaults to false.
    • timeout <number> maximum time to wait for in milliseconds. Defaults to 30000 (30 seconds).
  • returns: <Promise<ElementHandle>> Promise which resolves when element specified by selector string is added to DOM.

Wait for the selector to appear in page. If at the moment of calling the method the selector already exists, the method will return immediately. If the selector doesn't appear after the timeout milliseconds of waiting, the function will throw.

This method works across navigations:

const puppeteer = require('puppeteer');

puppeteer.launch().then(async browser => {
  const page = await browser.newPage();
  let currentURL;
  page.mainFrame()
    .waitForSelector('img')
    .then(() => console.log('First URL with image: ' + currentURL));
  for (currentURL of ['https://example.com', 'https://google.com', 'https://bbc.com'])
    await page.goto(currentURL);
  await browser.close();
});

class: ExecutionContext

The class represents a context for JavaScript execution. Examples of JavaScript contexts are:

  • each frame has a separate execution context
  • all kind of workers have their own contexts

executionContext.evaluate(pageFunction, ...args)

If the function, passed to the executionContext.evaluate, returns a Promise, then executionContext.evaluate would wait for the promise to resolve and return its value.

const executionContext = page.mainFrame().executionContext();
const result = await executionContext.evaluate(() => Promise.resolve(8 * 7));
console.log(result); // prints "56"

A string can also be passed in instead of a function.

console.log(await executionContext.evaluate('1 + 2')); // prints "3"

JSHandle instances can be passed as arguments to the executionContext.evaluate:

const oneHandle = await executionContext.evaluateHandle(() => 1);
const twoHandle = await executionContext.evaluateHandle(() => 2);
const result = await executionContext.evaluate((a, b) => a + b, oneHandle, twoHandle);
await oneHandle.dispose();
await twoHandle.dispose();
console.log(result); // prints '3'.

executionContext.evaluateHandle(pageFunction, ...args)

If the function, passed to the executionContext.evaluateHandle, returns a Promise, then executionContext.evaluteHandle would wait for the promise to resolve and return its value.

const context = page.mainFrame().executionContext();
const aHandle = await context.evaluateHandle(() => Promise.resolve(self));
aHandle; // Handle for the global object.

A string can also be passed in instead of a function.

const aHandle = await context.evaluateHandle('1 + 2'); // Handle for the '3' object.

JSHandle instances can be passed as arguments to the executionContext.evaluateHandle:

const aHandle = await context.evaluateHandle(() => document.body);
const resultHandle = await context.evaluateHandle(body => body.innerHTML, aHandle);
console.log(await resultHandle.jsonValue()); // prints body's innerHTML
await aHandle.dispose();
await resultHandle.dispose();

executionContext.queryObjects(prototypeHandle)

  • prototypeHandle <JSHandle> A handle to the object prototype.
  • returns: <JSHandle> A handle to an array of objects with this prototype

The method iterates JavaScript heap and finds all the objects with the given prototype.

// Create a Map object
await page.evaluate(() => window.map = new Map());
// Get a handle to the Map object prototype
const mapPrototype = await page.evaluateHandle(() => Map.prototype);
// Query all map instances into an array
const mapInstances = await page.queryObjects(mapPrototype);
// Count amount of map objects in heap
const count = await page.evaluate(maps => maps.length, mapInstances);
await mapInstances.dispose();
await mapPrototype.dispose();

class: JSHandle

JSHandle represents an in-page JavaScript object. JSHandles can be created with the page.evaluateHandle method.

const windowHandle = await page.evaluateHandle(() => window);
// ...

JSHandle prevents references JavaScript objects from garbage collection unless the handle is disposed. JSHandles are auto-disposed when their origin frame gets navigated or the parent context gets destroyed.

JSHandle instances can be used as arguments in page.$eval(), page.evaluate() and page.evaluateHandle methods.

jsHandle.asElement()

Returns either null or the object handle itself, if the object handle is an instance of ElementHandle.

jsHandle.dispose()

  • returns: <Promise> Promise which resolves when the object handle is successfully disposed.

The jsHandle.dispose method stops referencing the element handle.

jsHandle.executionContext()

Returns execution context the handle belongs to.

jsHandle.getProperties()

The method returns a map with property names as keys and JSHandle instances for the property values.

const handle = await page.evaluateHandle(() => ({window, document}));
const properties = await handle.getProperties();
const windowHandle = properties.get('window');
const documentHandle = properties.get('document');
await handle.dispose();

jsHandle.getProperty(propertyName)

Fetches a single property from the referenced object.

jsHandle.jsonValue()

Returns a JSON representation of the object. If the object has a toJSON function, it will not be called.

NOTE The method will return an empty JSON if the referenced object is not stringifiable. It will throw an error if the object has circular references.

class: ElementHandle

NOTE Class ElementHandle extends JSHandle.

ElementHandle represents an in-page DOM element. ElementHandles can be created with the page.$ method.

const puppeteer = require('puppeteer');

puppeteer.launch().then(async browser => {
  const page = await browser.newPage();
  await page.goto('https://google.com');
  const inputElement = await page.$('input[type=submit]');
  await inputElement.click();
  // ...
});

ElementHandle prevents DOM element from garbage collection unless the handle is disposed. ElementHandles are auto-disposed when their origin frame gets navigated.

ElementHandle instances can be used as arguments in page.$eval() and page.evaluate() methods.

elementHandle.$(selector)

The method runs element.querySelector within the page. If no element matches the selector, the return value resolve to null.

elementHandle.$$(selector)

The method runs element.querySelectorAll within the page. If no elements match the selector, the return value resolve to [].

elementHandle.$x(expression)

The method evluates the XPath expression relative to the elementHandle. If there's no such element, the method will resolve to null.

elementHandle.asElement()

elementHandle.boundingBox()

  • returns: <Promise<?Object>>
    • x <number> the x coordinate of the element in pixels.
    • y <number> the y coordinate of the element in pixels.
    • width <number> the width of the element in pixels.
    • height <number> the height of the element in pixels.

This method returns the bounding box of the element (relative to the main frame), or null if the element is not visible.

elementHandle.click([options])

  • options <Object>
    • button <string> left, right, or middle, defaults to left.
    • clickCount <number> defaults to 1. See UIEvent.detail.
    • delay <number> Time to wait between mousedown and mouseup in milliseconds. Defaults to 0.
  • returns: <Promise> Promise which resolves when the element is successfully clicked. Promise gets rejected if the element is detached from DOM.

This method scrolls element into view if needed, and then uses page.mouse to click in the center of the element. If the element is detached from DOM, the method throws an error.

elementHandle.dispose()

  • returns: <Promise> Promise which resolves when the element handle is successfully disposed.

The elementHandle.dispose method stops referencing the element handle.

elementHandle.executionContext()

elementHandle.focus()

Calls focus on the element.

elementHandle.getProperties()

The method returns a map with property names as keys and JSHandle instances for the property values.

const listHandle = await page.evaluateHandle(() => document.body.children);
const properties = await listHandle.getProperties();
const children = [];
for (const property of properties.values()) {
  const element = property.asElement();
  if (element)
    children.push(element);
}
children; // holds elementHandles to all children of document.body

elementHandle.getProperty(propertyName)

Fetches a single property from the objectHandle.

elementHandle.hover()

  • returns: <Promise> Promise which resolves when the element is successfully hovered.

This method scrolls element into view if needed, and then uses page.mouse to hover over the center of the element. If the element is detached from DOM, the method throws an error.

elementHandle.jsonValue()

Returns a JSON representation of the object. The JSON is generated by running JSON.stringify on the object in page and consequent JSON.parse in puppeteer.

NOTE The method will throw if the referenced object is not stringifiable.

elementHandle.press(key[, options])

  • key <string> Name of key to press, such as ArrowLeft. See USKeyboardLayout for a list of all key names.
  • options <Object>
    • text <string> If specified, generates an input event with this text.
    • delay <number> Time to wait between keydown and keyup in milliseconds. Defaults to 0.
  • returns: <Promise>

Focuses the element, and then uses keyboard.down and keyboard.up.

If key is a single character and no modifier keys besides Shift are being held down, a keypress/input event will also be generated. The text option can be specified to force an input event to be generated.

NOTE Modifier keys DO effect elementHandle.press. Holding down Shift will type the text in upper case.

elementHandle.screenshot([options])

This method scrolls element into view if needed, and then uses page.screenshot to take a screenshot of the element. If the element is detached from DOM, the method throws an error.

elementHandle.tap()

  • returns: <Promise> Promise which resolves when the element is successfully tapped. Promise gets rejected if the element is detached from DOM.

This method scrolls element into view if needed, and then uses touchscreen.tap to tap in the center of the element. If the element is detached from DOM, the method throws an error.

elementHandle.toString()

elementHandle.type(text[, options])

  • text <string> A text to type into a focused element.
  • options <Object>
    • delay <number> Time to wait between key presses in milliseconds. Defaults to 0.
  • returns: <Promise>

Focuses the element, and then sends a keydown, keypress/input, and keyup event for each character in the text.

To press a special key, like Control or ArrowDown, use elementHandle.press.

elementHandle.type('Hello'); // Types instantly
elementHandle.type('World', {delay: 100}); // Types slower, like a user

An example of typing into a text field and then submitting the form:

const elementHandle = await page.$('input');
await elementHandle.type('some text');
await elementHandle.press('Enter');

elementHandle.uploadFile(...filePaths)

  • ...filePaths <...string> Sets the value of the file input these paths. If some of the filePaths are relative paths, then they are resolved relative to current working directory.
  • returns: <Promise>

This method expects elementHandle to point to an input element.

class: Request

Whenever the page sends a request, the following events are emitted by puppeteer's page:

  • 'request' emitted when the request is issued by the page.
  • 'response' emitted when/if the response is received for the request.
  • 'requestfinished' emitted when the response body is downloaded and the request is complete.

If request fails at some point, then instead of 'requestfinished' event (and possibly instead of 'response' event), the 'requestfailed' event is emitted.

If request gets a 'redirect' response, the request is successfully finished with the 'requestfinished' event, and a new request is issued to a redirected url.

request.abort([errorCode])

  • errorCode <string> Optional error code. Defaults to failed, could be one of the following:
    • aborted - An operation was aborted (due to user action)
    • accessdenied - Permission to access a resource, other than the network, was denied
    • addressunreachable - The IP address is unreachable. This usually means that there is no route to the specified host or network.
    • connectionaborted - A connection timed out as a result of not receiving an ACK for data sent.
    • connectionclosed - A connection was closed (corresponding to a TCP FIN).
    • connectionfailed - A connection attempt failed.
    • connectionrefused - A connection attempt was refused.
    • connectionreset - A connection was reset (corresponding to a TCP RST).
    • internetdisconnected - The Internet connection has been lost.
    • namenotresolved - The host name could not be resolved.
    • timedout - An operation timed out.
    • failed - A generic failure occurred.
  • returns: <Promise>

Aborts request. To use this, request interception should be enabled with page.setRequestInterception. Exception is immediately thrown if the request interception is not enabled.

request.continue([overrides])

  • overrides <Object> Optional request overwrites, which can be one of the following:
    • url <string> If set, the request url will be changed
    • method <string> If set changes the request method (e.g. GET or POST)
    • postData <string> If set changes the post data of request
    • headers <Object> If set changes the request HTTP headers
  • returns: <Promise>

Continues request with optional request overrides. To use this, request interception should be enabled with page.setRequestInterception. Exception is immediately thrown if the request interception is not enabled.

request.failure()

  • returns: <?Object> Object describing request failure, if any
    • errorText <string> Human-readable error message, e.g. 'net::ERR_FAILED'.

The method returns null unless this request was failed, as reported by requestfailed event.

Example of logging all failed requests:

page.on('requestfailed', request => {
  console.log(request.url + ' ' + request.failure().errorText);
});

request.headers()

  • returns: <Object> An object with HTTP headers associated with the request. All header names are lower-case.

request.method()

  • returns: <string> Request's method (GET, POST, etc.)

request.postData()

  • returns: <string> Request's post body, if any.

request.resourceType()

Contains the request's resource type as it was perceived by the rendering engine. ResourceType will be one of the following: document, stylesheet, image, media, font, script, texttrack, xhr, fetch, eventsource, websocket, manifest, other.

request.respond(response)

  • response <Object> Response that will fulfill this request
    • status <number> Response status code, defaults to 200.
    • headers <Object> Optional response headers
    • contentType <string> If set, equals to setting Content-Type response header
    • body <Buffer|string> Optional response body
  • returns: <Promise>

Fulfills request with given response. To use this, request interception should be enabled with page.setRequestInterception. Exception is thrown if request interception is not enabled.

An example of fulfilling all requests with 404 responses:

await page.setRequestInterception(true);
page.on('request', request => {
  request.respond({
    status: 404,
    contentType: 'text/plain',
    body: 'Not Found!'
  });
});

NOTE Mocking responses for dataURL requests is not supported. Calling request.respond for a dataURL request is a noop.

request.response()

  • returns: <?Response> A matching Response object, or null if the response has not been received yet.

request.url()

  • returns: <string> URL of the request.

class: Response

Response class represents responses which are received by page.

response.buffer()

  • returns: <Promise<Buffer>> Promise which resolves to a buffer with response body.

response.headers()

  • returns: <Object> An object with HTTP headers associated with the response. All header names are lower-case.

response.json()

  • returns: <Promise<Object>> Promise which resolves to a JSON representation of response body.

This method will throw if the response body is not parsable via JSON.parse.

response.ok()

Contains a boolean stating whether the response was successful (status in the range 200-299) or not.

response.request()

response.status()

Contains the status code of the response (e.g., 200 for a success).

response.text()

  • returns: <Promise<string>> Promise which resolves to a text representation of response body.

response.url()

Contains the URL of the response.

class: Target

target.page()

If the target is not of type "page", returns null.

target.type()

Identifies what kind of target this is. Can be "page", "service_worker", or "other".

target.url()

class: Coverage

Coverage gathers information about parts of JavaScript and CSS that were used by the page.

An example of using JavaScript and CSS coverage to get percentage of initially executed code:

// Enable both JavaScript and CSS coverage
await Promise.all([
  page.startJSCoverage(),
  page.startCSSCoverage()
]);
// Navigate to page
await page.goto('https://example.com');
// Disable both JavaScript and CSS coverage
const [jsCoverage, cssCoverage] = await Promise.all([
  page.stopJSCoverage(),
  page.stopCSSCoverage(),
]);
let totalBytes = 0;
let usedBytes = 0;
const coverage = [].concat(jsCoverage, cssCoverage);
for (const entry of coverage) {
  totalBytes += entry.text.length;
  for (const range of entry.ranges)
    usedBytes += range.end - range.start - 1;
}
console.log(`Bytes used: ${usedBytes / totalBytes * 100}%`);

coverage.startCSSCoverage(options)

  • options <Object> Set of configurable options for coverage
    • resetOnNavigation <boolean> Whether to reset coverage on every navigation. Defaults to true.
  • returns: <Promise> Promise that resolves when coverage is started

coverage.startJSCoverage(options)

  • options <Object> Set of configurable options for coverage
    • resetOnNavigation <boolean> Whether to reset coverage on every navigation. Defaults to true.
  • returns: <Promise> Promise that resolves when coverage is started

coverage.stopCSSCoverage()

  • returns: <Promise<Array<Object>>> Promise that resolves to the array of coverage reports for all stylesheets
    • url <string> StyleSheet URL
    • text <string> StyleSheet content
    • ranges <Array<Object>> StyleSheet ranges that were used. Ranges are sorted and non-overlapping.
      • start <number> A start offset in text, inclusive
      • end <number> An end offset in text, exclusive

NOTE CSS Coverage doesn't include dynamically injected style tags without sourceURLs.

coverage.stopJSCoverage()

  • returns: <Promise<Array<Object>>> Promise that resolves to the array of coverage reports for all non-anonymous scripts
    • url <string> Script URL
    • text <string> Script content
    • ranges <Array<Object>> Script ranges that were executed. Ranges are sorted and non-overlapping.
      • start <number> A start offset in text, inclusive
      • end <number> An end offset in text, exclusive

NOTE JavaScript Coverage doesn't include anonymous scripts; however, scripts with sourceURLs are reported.