Beginner’s Guide to Playwright Automation
What is Playwright?
Playwright is an open-source framework for cross-browser automation and end-to-end web application testing. It was designed to be a fast, reliable, robust, and evergreen test automation framework, and its API supports modern rendering engines that include Chromium, WebKit, and Firefox. Playwright tests run on Windows, Linux, and macOS, locally or on your continuous integration pipeline, and headless or headed. Playwright supports several programming languages, including TypeScript, JavaScript, Python, .NET, and Java.
End to end testing with Playwright
Playwright was created by the same engineering team that built Puppeteer. The Playwright team created Playwright to extend Puppeteer’s UI automation capabilities to all rendering engines, no longer just supporting Chromium. Microsoft engineers built on top of Puppeteer’s core features to provide a testing framework that met the challenges presented by today’s increasingly complex, feature-rich web applications and software development life cycles.
Modern web applications are built as distributed systems that comprise separate components and services. This architecture is equally reflected in team organization with larger teams split into smaller pods, each responsible for a specific product requirement. Within this distributed and service-oriented model, automated end-to-end tests must simulate real-world user test scenarios and verify that an application’s moving parts work together, as intended. End-to-end tests provide disparate product teams with the confidence needed to determine if a web application is working or not.
End-to-end tests have the reputation of being flaky and slow, while also requiring a lot of maintenance. These limitations are reflected in the Test Pyramid’s recommendation that end-to-end tests should be kept at a minimum due to their unreliability and difficulty in handling complex, feature-heavy, and service-oriented web applications.
Playwright overcomes flaky and slow tests by communicating with rendering engines via the WebSocket protocol, instead of through multiple HTTP requests, as is done with other web automation testing tools like Selenium. Playwright communicates all requests through a single web socket connection that remains active until all tests have been completed. This reduces points of test failure during test execution, providing a stable and fast solution.
Playwright Features
While taking a simplified approach to its design, Playwright offers many features that make it unique, but competitive with several other leading test automation tools, like Cypress and Puppeteer. While we’ve discussed some of the key features in more detail above, some additional noteworthy features include:
- Mobile Emulation: Playwright allows you to emulate mobile devices, such as iPhones and iPads, and test how your web application behaves on different screen sizes and orientations.
- Headless Mode: You can run your tests in a headless browser, which is useful for CI/CD pipelines and for running tests in environments where a graphical interface is not available.
- Video Recording: Playwright automatically records videos of your tests, which can be useful for debugging and for creating visual regression tests.
- Cross Browser Testing: Playwright supports multiple browsers, including Chromium, Firefox, and WebKit, allowing you to test your application across different browsers.
- Programming Language Support: Playwright is available in several programming languages, including JavaScript, TypeScript, Python, .NET, and Java, making it accessible to a wide range of developers.
- Comprehensive API: Playwright provides a comprehensive API for automating browser actions, such as navigation, page interaction, and element manipulation.
- CI/CD Integration: Playwright integrates seamlessly with popular CI/CD platforms, such as GitHub Actions, Jenkins, and CircleCI, allowing you to run your tests as part of your continuous integration and delivery process.
- Visual Testing: Playwright supports visual testing, allowing you to compare screenshots of your web application and detect visual changes.
- Code Generation: Playwright includes a code generator that can generate code for your tests, saving you time and reducing the risk of errors.
Main use cases
- Test automation in modern web applications: verifying that the features we are exposing our users/customers to are actually behaving as expected.
- Cross-browser testing: ensuring applications are working consistently across browsers and rendering engines.
- Taking screenshots of web pages: useful for a variety of different uses going from simple archiving to automated comparison for e.g. visual testing.
- Scraping web sites for data: extracting data from websites for later retrieval or analysis.
- Automating interaction of web pages: speed up and scale any sort of sequence of actions we would like to perform on a website automatically.
In this guide you will find multiple examples showing how to leverage Playwright, with a focus on test automation / active reliability.
Growth and Adoption
Since its release in January 2020 by Microsoft, Playwright has experienced a surge in usage and popularity. As of March 2023, its GitHub repository has received 48.4k stars and 2.4k forks, and is currently averaging more than 1.2 million NPM downloads per week. Playwright is used by enterprise and open-source development projects alike, including Adobe Spectrum, Visual Studio Code, and React Navigation.