库

介绍

¥Introduction

Playwright Library 提供用于启动浏览器并与浏览器交互的统一 API，而 Playwright Test 则提供所有这些以及完全托管的端到端测试运行程序和体验。

¥Playwright Library provides unified APIs for launching and interacting with browsers, while Playwright Test provides all this plus a fully managed end-to-end Test Runner and experience.

在大多数情况下，对于端到端测试，你需要直接使用 @playwright/test（Playwright 测试），而不是 playwright（Playwright 库）。要开始 Playwright 测试，请遵循入门指南。

¥Under most circumstances, for end-to-end testing, you'll want to use @playwright/test (Playwright Test), and not playwright (Playwright Library) directly. To get started with Playwright Test, follow the Getting Started Guide.

使用库时的差异

¥Differences when using library

库示例

¥Library Example

以下是直接使用 Playwright Library 启动 Chromium、转到页面并检查其标题的示例：

¥The following is an example of using the Playwright Library directly to launch Chromium, go to a page, and check its title:

TypeScript
JavaScript

import { chromium, devices } from 'playwright';
import assert from 'node:assert';

(async () => {
  // Setup
  const browser = await chromium.launch();
  const context = await browser.newContext(devices['iPhone 11']);
  const page = await context.newPage();

  // The actual interesting bit
  await context.route('**.jpg', route => route.abort());
  await page.goto('https://example.com/');

  assert(await page.title() === 'Example Domain'); // 👎 not a Web First assertion

  // Teardown
  await context.close();
  await browser.close();
})();

const assert = require('node:assert');
const { chromium, devices } = require('playwright');

(async () => {
  // Setup
  const browser = await chromium.launch();
  const context = await browser.newContext(devices['iPhone 11']);
  const page = await context.newPage();

  // The actual interesting bit
  await context.route('**.jpg', route => route.abort());
  await page.goto('https://example.com/');

  assert(await page.title() === 'Example Domain'); // 👎 not a Web First assertion

  // Teardown
  await context.close();
  await browser.close();
})();

使用 node my-script.js 运行它。

¥Run it with node my-script.js.

测试实例

¥Test Example

实现类似行为的测试如下所示：

¥A test to achieve similar behavior, would look like:

TypeScript
JavaScript

import { expect, test, devices } from '@playwright/test';

test.use(devices['iPhone 11']);

test('should be titled', async ({ page, context }) => {
  await context.route('**.jpg', route => route.abort());
  await page.goto('https://example.com/');

  await expect(page).toHaveTitle('Example');
});

const { expect, test, devices } = require('@playwright/test');

test.use(devices['iPhone 11']);

test('should be titled', async ({ page, context }) => {
  await context.route('**.jpg', route => route.abort());
  await page.goto('https://example.com/');

  await expect(page).toHaveTitle('Example');
});

使用 npx playwright test 运行它。

¥Run it with npx playwright test.

主要差异

¥Key Differences

需要注意的主要区别如下：

¥The key differences to note are as follows:

	库	测试
安装	`npm install playwright`	`npm init playwright@latest` - 注意 `install` 与 `init`
安装浏览器	安装 `@playwright/browser-chromium`、`@playwright/browser-firefox` 和/或 `@playwright/browser-webkit`	`npx playwright install` 或 `npx playwright install chromium` 为单个
`import` 来自	`playwright`	`@playwright/test`
初始化	明确需要： Pick a browser to use, e.g. `chromium` Launch browser with browserType.launch() Create a context with browser.newContext(), and pass any context options explicitly, e.g. `devices['iPhone 11']` Create a page with browserContext.newPage()	为每个开箱即用的测试提供隔离的 `page` 和 `context`，以及其他内置夹具。没有显式的创建。如果测试在其参数中引用，则测试运行器将为测试创建它们。（即延迟初始化）
断言	没有内置的 Web 优先断言	Web 优先断言喜欢： expect(page).toHaveTitle() expect(page).toHaveScreenshot() 自动等待并重试以满足条件。

Close context with browserContext.close()
Close browser with browser.close()

| No explicit close of built-in fixtures; the Test Runner will take care of it. | Running | When using the Library, you run the code as a node script, possibly with some compilation first. | When using the Test Runner, you use the npx playwright test command. Along with your config, the Test Runner handles any compilation and choosing what to run and how to run it. |

除上述内容外，Playwright Test 作为一个功能齐全的测试运行程序，还包括：

¥In addition to the above, Playwright Test, as a full-featured Test Runner, includes:

配置矩阵和项目：在上面的示例中，在 Playwright Library 版本中，如果我们想使用不同的设备或浏览器运行，我们必须修改脚本并探查信息。使用 Playwright Test，我们只需在一个位置指定配置矩阵，它就会在每种配置下运行一个测试。

¥Configuration Matrix and Projects: In the above example, in the Playwright Library version, if we wanted to run with a different device or browser, we'd have to modify the script and plumb the information through. With Playwright Test, we can just specify the matrix of configurations in one place, and it will create run the one test under each of these configurations.
并行化

¥Parallelization
Web 优先断言

¥Web-First Assertions
报告

¥Reporting
重试

¥Retries
轻松启用跟踪

¥Easily Enabled Tracing
和更多…

¥and more…

用法

¥Usage

使用 npm 或 Yarn 在 Node.js 项目中安装 Playwright 库。参见系统要求。

¥Use npm or Yarn to install Playwright library in your Node.js project. See system requirements.

npm i -D playwright

你还需要安装浏览器 - 手动或添加一个可以自动为你完成此操作的包。

¥You will also need to install browsers - either manually or by adding a package that will do it for you automatically.

# Download the Chromium, Firefox and WebKit browser
npx playwright install chromium firefox webkit

# Alternatively, add packages that will download a browser upon npm install
npm i -D @playwright/browser-chromium @playwright/browser-firefox @playwright/browser-webkit

有关更多选项，请参阅管理浏览器。

¥See managing browsers for more options.

安装后，你可以在 Node.js 脚本中导入 Playwright，并启动 3 个浏览器（chromium、firefox 和 webkit）中的任意一个。

¥Once installed, you can import Playwright in a Node.js script, and launch any of the 3 browsers (chromium, firefox and webkit).

const { chromium } = require('playwright');

(async () => {
  const browser = await chromium.launch();
  // Create pages, interact with UI elements, assert values
  await browser.close();
})();

Playwright API 是异步的并返回 Promise 对象。我们的代码示例使用异步/等待模式来简化可读性。该代码封装在一个未命名的异步箭头函数中，该函数正在调用自身。

¥Playwright APIs are asynchronous and return Promise objects. Our code examples use the async/await pattern to ease readability. The code is wrapped in an unnamed async arrow function which is invoking itself.

(async () => { // Start of async arrow function
  // Function code
  // ...
})(); // End of the function and () to invoke itself

第一个脚本

¥First script

在我们的第一个脚本中，我们将导航到 https://playwright.nodejs.cn/ 并在 WebKit 中截取屏幕截图。

¥In our first script, we will navigate to https://playwright.nodejs.cn/ and take a screenshot in WebKit.

const { webkit } = require('playwright');

(async () => {
  const browser = await webkit.launch();
  const page = await browser.newPage();
  await page.goto('https://playwright.nodejs.cn/');
  await page.screenshot({ path: `example.png` });
  await browser.close();
})();

默认情况下，Playwright 以无头模式运行浏览器。要查看浏览器 UI，请在启动浏览器时传递 headless: false 标志。你还可以使用 slowMo 来减慢执行速度。在调试工具 section 中了解更多信息。

¥By default, Playwright runs the browsers in headless mode. To see the browser UI, pass the headless: false flag while launching the browser. You can also use slowMo to slow down execution. Learn more in the debugging tools section.

firefox.launch({ headless: false, slowMo: 50 });

录制脚本

¥Record scripts

命令行工具可用于记录用户交互并生成 JavaScript 代码。

¥Command line tools can be used to record user interactions and generate JavaScript code.

npx playwright codegen wikipedia.org

浏览器下载

¥Browser downloads

要下载 Playwright 浏览器，请运行：

¥To download Playwright browsers run:

# Explicitly download browsers
npx playwright install

或者，你可以添加 @playwright/browser-chromium、@playwright/browser-firefox 和 @playwright/browser-webkit 软件包，以便在软件包安装过程中自动下载相应的浏览器。

¥Alternatively, you can add @playwright/browser-chromium, @playwright/browser-firefox and @playwright/browser-webkit packages to automatically download the respective browser during the package installation.

# Use a helper package that downloads a browser on npm install
npm install @playwright/browser-chromium

在防火墙或代理后面下载

¥Download behind a firewall or a proxy

传递 HTTPS_PROXY 环境变量以通过代理下载。

¥Pass HTTPS_PROXY environment variable to download through a proxy.

Bash
PowerShell
Batch

# Manual
HTTPS_PROXY=https://192.0.2.1 npx playwright install

# Through @playwright/browser-chromium, @playwright/browser-firefox
# and @playwright/browser-webkit helper packages
HTTPS_PROXY=https://192.0.2.1 npm install

# Manual
$Env:HTTPS_PROXY=https://192.0.2.1
npx playwright install

# Through @playwright/browser-chromium, @playwright/browser-firefox
# and @playwright/browser-webkit helper packages
$Env:HTTPS_PROXY=https://192.0.2.1
npm install

# Manual
set HTTPS_PROXY=https://192.0.2.1
npx playwright install

# Through @playwright/browser-chromium, @playwright/browser-firefox
# and @playwright/browser-webkit helper packages
set HTTPS_PROXY=https://192.0.2.1
npm install

从工件存储库下载

¥Download from artifact repository

默认情况下，Playwright 从 Microsoft 的 CDN 下载浏览器。传递 PLAYWRIGHT_DOWNLOAD_HOST 环境变量以从内部工件存储库下载。

¥By default, Playwright downloads browsers from Microsoft's CDN. Pass PLAYWRIGHT_DOWNLOAD_HOST environment variable to download from an internal artifacts repository instead.

Bash
PowerShell
Batch

# Manual
PLAYWRIGHT_DOWNLOAD_HOST=192.0.2.1 npx playwright install

# Through @playwright/browser-chromium, @playwright/browser-firefox
# and @playwright/browser-webkit helper packages
PLAYWRIGHT_DOWNLOAD_HOST=192.0.2.1 npm install

# Manual
$Env:PLAYWRIGHT_DOWNLOAD_HOST=192.0.2.1
npx playwright install

# Through @playwright/browser-chromium, @playwright/browser-firefox
# and @playwright/browser-webkit helper packages
$Env:PLAYWRIGHT_DOWNLOAD_HOST=192.0.2.1
npm install

# Manual
set PLAYWRIGHT_DOWNLOAD_HOST=192.0.2.1
npx playwright install

# Through @playwright/browser-chromium, @playwright/browser-firefox
# and @playwright/browser-webkit helper packages
set PLAYWRIGHT_DOWNLOAD_HOST=192.0.2.1
npm install

跳过浏览器下载

¥Skip browser download

在某些情况下，希望完全避免浏览器下载，因为浏览器二进制文件是单独管理的。这可以通过在安装软件包之前设置 PLAYWRIGHT_SKIP_BROWSER_DOWNLOAD 变量来完成。

¥In certain cases, it is desired to avoid browser downloads altogether because browser binaries are managed separately. This can be done by setting PLAYWRIGHT_SKIP_BROWSER_DOWNLOAD variable before installing packages.

Bash
PowerShell
Batch

# When using @playwright/browser-chromium, @playwright/browser-firefox
# and @playwright/browser-webkit helper packages
PLAYWRIGHT_SKIP_BROWSER_DOWNLOAD=1 npm install

# When using @playwright/browser-chromium, @playwright/browser-firefox
# and @playwright/browser-webkit helper packages
$Env:PLAYWRIGHT_SKIP_BROWSER_DOWNLOAD=1
npm install

# When using @playwright/browser-chromium, @playwright/browser-firefox
# and @playwright/browser-webkit helper packages
set PLAYWRIGHT_SKIP_BROWSER_DOWNLOAD=1
npm install

TypeScript 支持

¥TypeScript support

Playwright 包含对 TypeScript 的内置支持。类型定义将自动导入。建议使用类型检查来改善 IDE 体验。

¥Playwright includes built-in support for TypeScript. Type definitions will be imported automatically. It is recommended to use type-checking to improve the IDE experience.

在 JavaScript 中

¥In JavaScript

将以下内容添加到 JavaScript 文件的顶部，以在 VS Code 或 WebStorm 中进行类型检查。

¥Add the following to the top of your JavaScript file to get type-checking in VS Code or WebStorm.

// @ts-check
// ...

或者，你可以使用 JSDoc 设置变量的类型。

¥Alternatively, you can use JSDoc to set types for variables.

/** @type {import('playwright').Page} */
let page;

在 TypeScript 中

¥In TypeScript

TypeScript 支持开箱即用。类型也可以显式导入。

¥TypeScript support will work out-of-the-box. Types can also be imported explicitly.

let page: import('playwright').Page;

介绍​

使用库时的差异​

库示例​

测试实例​

主要差异​

用法​

第一个脚本​

录制脚本​

浏览器下载​

TypeScript 支持​

在 JavaScript 中​

在 TypeScript 中​

介绍