Playwright Overview
Playwright is a relatively new browser automation framework that has gained popularity due to its modern approach to web testing. It supports multiple programming languages, but it is particularly well-suited for JavaScript and TypeScript users.Playwright Key Features
- Out-of-the-box Test Framework: Playwright comes bundled with Playwright Test, providing a comprehensive test automation framework that handles test execution, reporting, assertions, and more.
- Auto-Wait Mechanism: Playwright intelligently waits for elements to be ready before interacting with them, reducing the need for manual wait statements.
- Cross-Browser Testing: It supports Chromium, Firefox, and WebKit, making it useful for testing across different browsers.
- Parallel Execution: Built-in support for running tests in parallel to speed up execution time.
- Trace Viewer: A powerful debugging tool that records test execution, allowing you to inspect the behavior and identify issues.
- Headless Mode: Ability to run tests in headless mode for faster execution and CI/CD pipelines.
How to Run Playwright Tests
-
Install Playwright using npm:
-
Set up a test script using
@playwright/test
: -
Run the test with the Playwright CLI:
Selenium Overview
Selenium has been a mainstay in browser automation for over a decade. It is widely used across the industry and supports multiple languages, including Java, Python, C#, and JavaScript. Selenium is a browser automation tool rather than a full-fledged testing framework, which means you’ll need to add additional libraries for assertions, reporting, and parallel test execution.Selenium Key Features
- Multi-Language Support: Selenium supports many programming languages, making it flexible for teams with diverse tech stacks.
- Cross-Browser Testing: It works with all major browsers, including Chrome, Firefox, Safari, and Edge.
- WebDriver Protocol: Selenium uses the WebDriver protocol, which is a standard for browser automation.
- Support for Real Devices: It integrates well with cloud services for testing on real devices.
- Large Ecosystem: There are many plugins, libraries, and resources available for Selenium.
Setting up and running Selenium tests
Here’s how to run a Selenium test in NodeJS-
Install Selenium WebDriver
You can add Selenium WebDriver to your project using NPM:
Selenium WebDriver is the library that allows your tests to interact with browsers.
Writing a Basic Selenium Test
-
Import the Selenium WebDriver Module
In your test file (e.g.,
test.js
), import theselenium-webdriver
package: -
Set Up the Browser Driver
Use the
Builder
to configure your test environment. Here is a simple example:
Running the Test
To run your test, executenode test.js
in your terminal
This command launches a browser, performs the specified actions, and then closes the browser. You should see any console output you added, such as the page title.
Playwright vs Selenium: Key Differences
While Playwright and Selenium are both used for similar roles as test automation. And both are focused on operating a browser automatically, the difference in their backgrounds, core userbase, and ages show up in a number of implementation details.Feature | Playwright | Selenium |
---|---|---|
Language | Primarily used with JavaScript/TypeScript; also supports Python, Java, and .NET. | Supports a wider range of languages, suitable for diverse tech stacks. |
Test Runner Frameworks | Comes with Playwright Test, a built-in test runner. | Does not include a test runner; requires integration with frameworks like JUnit, TestNG, or PyTest. |
Element Locators | Uses modern CSS selectors and locators like getByRole , getByText , getByTestId . | Uses traditional locators such as id , class , xpath , cssSelector . |
Waits | Automatic waiting for elements, reducing the need for manual sleep statements. | Requires explicit or implicit waits, leading to more complex synchronization issues. |
Ease of Installation | Easy to install with a single npm command. | Requires installing browser drivers and additional setup components. |
Trace Viewer | Includes a built-in trace viewer for debugging. | No built-in trace viewer; debugging requires additional tools. |
Prerequisites | Basic knowledge of JavaScript or TypeScript. | More flexibility with languages but requires additional setup. |
Operating Systems | Supports Windows, macOS, and Linux. | Supports Windows, macOS, and Linux. |
Open Source | Actively gaining traction and evolving rapidly. | Established community, but some resources may be outdated. |
Parallel Testing | Built-in support for parallel test execution. | Requires a third-party framework for parallel runs. |
Architecture | Modern architecture optimized for speed and reliability. | Based on the WebDriver protocol, which is older. |
Browsers Supported | Chromium, Firefox, WebKit. | Chrome, Firefox, Safari, Edge, and more. |
Documentation & Community | Well-documented; community support is growing. | Established community with extensive resources. |
Real Devices Support | Limited real device testing options. | Better integration with cloud-based real device testing services. |
Plugins | Fewer plugins but growing support. | Rich ecosystem of plugins for various purposes. |
Visual Testing | Native support for visual regression testing. | Requires third-party libraries for visual testing. |
Test Recording & Screenshots | Built-in support for test recording and screenshots. | Screenshots supported; test recording needs external tools. |
Assertions | Comes with built-in assertions. | Needs an external assertion library. |
Test Reporting | Built-in test reporting features. | Needs external reporting libraries. |
API Automation | Supports API testing natively. | Focused on browser automation only. |
Performance | Generally faster, especially in headless mode. | Slower due to the WebDriver protocol overhead. |
Selenium Examples
Here’s a test that simulates a user logging in and loading recent transactions. The automation then takes a screenshot.Playwright Examples
Here’s the same test in Playwright:- Playwright uses modern css locators rather than finding by ID or class. ID and class can shift on an element when all that’s happening is a visual refresh of the site. We don’t want our tests to break in this situation!
- Playwright includes auto-waiting, so there’s no need to add manual timeouts to our code.
Playwright vs Selenium: Pros & Cons
Playwright
Pros: Easy to get started, built-in test framework, faster execution, modern architecture, better support for JavaScript/TypeScript. Cons: Fewer legacy languages supported (e.g. C), limited real device testing.Selenium
Pros: Established tool with a large community, supports many languages, better integration with real device testing. Cons: More setup required, slower execution, higher learning curve for productivity.Playwright vs Selenium: Which Solution to Choose?
When to Use Playwright
- If you’re starting a new project and want fast productivity.
- If your team is experienced with JavaScript or TypeScript.
- If you need built-in features like auto-waiting, test recording, and API testing.
When to Use Selenium
- If you’re joining an established project that already uses Selenium.
- If you require deep device simulation