Starting a browser and subsequently running the test cases on the browsers is a crucial aspect of web automation testing. However, while executing tests using Selenium ChromeDriver, developers typically encounter challenges like slow browser rendering, interference from other applications operating on the system, and so on.
Besides these, nowadays most of the CI systems are non-UI (like Unix-based systems).
Consequently, executing the test cases on those systems requires a method to run the test cases in a non-UI mode, and this is where the headless browser becomes relevant, facilitating the execution of Selenium Headless Browser tests in a non-UI mode. It saves time while running several complex test cases in different phases.
Nearly all contemporary browsers offer the ability to operate in headless mode. In this article, we will discuss these headless browsers and how they can be used for running the Selenium test cases in headless mode. We will also discuss the steps to configure ChromeDriver to initiate the Chrome browser in headless mode through Selenium.
What is Selenium ChromeDriver?
Selenium is a freely available automation testing framework designed for testing web applications through interactions with web browsers. It is compatible with multiple browsers such as Chrome, Firefox, Internet Explorer, and Safari.
Testers typically employ Chrome Driver alongside Selenium to run tests on the Chrome browser. Chrome Drivers are executable files utilized by Selenium WebDriver to start Google Chrome through the Chrome DevTools Protocol. It is open source as well and can execute tests on Chrome Browsers by adjusting it according to the requirements.
What is Headless Browser Testing
Headless browser testing is similar to web UI testing, except it employs tools that allow tests to run without loading an entire web browser. These tools convey requests in the same manner that a web browser does, and they receive the same HTML, CSS, and JavaScript files.
It refers to conducting automated tests on a web browser that runs in headless mode, which means it lacks a graphical user interface (GUI). In this testing technique, the browser performs commands and interacts with web pages programmatically, but testers do not see the real browser window. Instead, the testing procedure occurs in the background, which is faster and more resource-efficient than testing with a visible browser interface.
Selenium headless browser testing using Selenium WebDriver to automate testing on a web browser that runs in a headless state. In this context, “headless” refers to the browser running without a graphical user interface (GUI). This approach allows for automated interactions with web pages without displaying a visible browser window.
Benefits of Selenium ChromeDriver in Headless Testing
Because of its unique features and capabilities, headless testing with Selenium ChromeDriver is essential in various aspects of web data collection, testing, and automation. The following key factors highlight the importance of the Selenium headless browser testing:
Increased Efficiency In Automated Testing
Headless testing with Selenium ChromeDriver speeds up the execution of automated test scripts by removing the requirement to show a graphical interface. It is ideal for running tests within continuous integration and deployment pipelines, resulting in faster feedback on code changes.
Resource Optimization
The Selenium headless browser uses fewer system resources compared to regular browsers because it does not display a visible browser window. Additionally, a Selenium headless browser facilitates more efficient use of computing resources, rendering it ideal for extensive or concurrent test executions.
Facilitates Web Scraping And Data Extraction
Selenium’s headless browser aids in web scraping by browsing websites, engaging with dynamic content, and programmatically retrieving data. Additionally, it allows for discrete and effective data collection without displaying a browser window, making it ideal for automated data collection.
Enables SEO Testing
It is essential for automating SEO testing and enabling content analysis of web pages to guarantee compliance with SEO guidelines. Additionally, the Selenium headless browser automatically checks for structured data, meta tags, and page loading speed without requiring manual intervention.
Provides Security Benefits
For automated tasks, the Selenium headless browser offers a more secure approach. It is less susceptible to certain kinds of attacks since it does not provide a graphical user interface. However, this works well in situations when security is a top priority, like testing headless browsers with Selenium ChromeDriver under secure environments.
Scalability
Another significant advantage of headless execution is scalability. Headless testing can easily scale to operate on multiple devices or in the cloud since it can work in the background. This enables the more efficient performance of extensive automated tests or web scraping tasks without requiring expensive device purchases.
Platform Independence
Any operating system, such as Windows, macOS, and Linux, can execute a Selenium ChromeDriver headless test. This removes the concern of compatibility problems when testing web applications in different environments and platforms. Because such testing doesn’t need a graphical user interface, they can operate in virtual environments or on lower-capacity devices, which can assist in conserving money and resources.
Reduced Cost
For developers and testers, this approach can result in cost savings. Selenium ChromeDriver headless testing, which does not require a graphical user interface, can save them money on devices. As a result, this can be used in virtualized environments or on less capable devices.
Continuous Integration
Workflows for continuous integration and continuous delivery (CI/CD) include the implementation of Selenium headless testing. By automating tests, developers can be confident that new code modifications do not impact current functionality. To execute tests automatically and ensure that code modifications are released only after successfully passing the tests, the headless browser Selenium can be incorporated into CI/CD pipelines.
Limitations of Executing Selenium ChromeDriver Tests in Headless Mode
Although running headless tests with Selenium ChromeDriver has several advantages, there are a few limitations to be cautious of as well:
- Limited browser support: For some tasks, this might not be an option because some browsers do not allow a headless mode of operation.
- Limited debugging capabilities: Because headless mode lacks a graphical user interface, debugging test failures and other issues can be more challenging.
- Limited visualization: Visual regression testing is one of the testing scenarios that could not be feasible. Visualizing the results of tests and comprehending the behavior of the application can be simpler using a graphical user interface (GUI).
- Minimal support for browser plugins: A browser in headless mode lacks support for plugins, thus reducing the usefulness of the tests that are performed.
Why Headless Testing Is Better With Selenium ChromeDriver
Using a Selenium ChromeDriver for headless testing offers several advantages contributing to efficient and reliable automated testing processes, especially when performance and scalability are critical. This makes it an appealing choice for browser automation. Here are key reasons why this technique is a preferred choice for testing:
Open Source and Widely Adopted
A broad community of developers and testers can use the Selenium headless browser because it is an open-source tool. However, the widespread use of the Selenium headless browser provides plenty of resources, documentation, and support from the community.
Cross-Browser Compatibility
Selenium supports automation on various browsers like Chrome, Firefox, Safari, Internet Explorer, and Microsoft Edge. When combined with the appropriate driver (such as ChromeDriver for Chrome), it allows testers to write scripts that work across these different browsers without the need for manual input.
No doubt, Selenium is a powerful tool for automating browser-based testing, and combining it with services like LambdaTest can streamline the testing process, especially for headless testing and cross-browser compatibility.
LambdaTest is an AI-powered platform for test orchestration and execution, allowing for the large-scale execution of both automated and manual tests. Testers can also perform automated and real-time testing using the cloud Selenium Grid of over 3000 environments and real mobile devices, enabling cross-browser testing across real browsers and operating systems. This allows the simulation of various real-world environments without having to manually configure them locally.
Additionally, this AI testing platform offers headless testing capabilities, allowing Selenium tests to run in headless mode on browsers like Chrome, Firefox, and Safari, without requiring to set up the infrastructure or deal with browser installations. This speeds up the testing process and decreases execution time, thus, improving the application testing process. By automatically adapting and stabilizing testing through machine learning, the platform reduces the maintenance load associated with frequent application upgrades.
Moreover, the parallel testing capabilities of this platform allow testers to perform multiple tests parallely across different devices, platforms, application versions, and browsers, which reduces the testing time.
Provides Selenium WebDriver Interface
A WebDriver interface offered by the Selenium headless browser enables scripting in a variety of programming languages, including Java, Python, C#, and others. But using the WebDriver interface, testers can control browsers for testing and interact with web pages programmatically.
Allows Efficient Automation
Headless testing with Selenium ChromeDriver supports the scripting of repetitive tasks and user interactions with web applications. When using the Selenium headless browser, efficient automated testing can be performed without the requirement for a visible browser window.
Enhances Seamless Compatibility with Testing Frameworks
Selenium works effortlessly with widely used testing frameworks like JUnit, TestNG, and more. This alignment improves the structure and arrangement of test scripts, resulting in more efficient test development and execution.
Continuous Integration (CI) Support
Automated testing is essential to the development and deployment process, and Selenium is ideally suited for incorporation into CI pipelines. On the other hand, CI setups that use Selenium headless testing offer prompt feedback on code modifications.
Headless Testing Setup with Selenium Chrome Driver
To set up Selenium ChromeDriver in headless mode, testers first need to configure the WebDriver with the proper parameters. Here’s a step-by-step instruction.
- Download and Setup ChromeDriver- Download the ChromeDriver executable from the official ChromeDriver website. Place the executable in a location accessible by the task. Add the path to ChromeDriver to the system’s PATH environment variable.
- Set Up Selenium WebDriver Dependencies- Add the Selenium Java bindings to the task. Testers can download them from the official Selenium website. Add the JAR files to the task’s classpath. Create a new instance of ChromeDriver in the Selenium code.
- Configure Chrome Options for Headless Mode- In the Java code, configure Chrome options to run the browser in headless mode.
- Run Script- Write Selenium test code and run it using the ChromeDriver. Execute the Java class, and if all configurations are correct, the script will launch Chrome in headless mode.
Additional Notes
- Adjust Chrome options based on the requirements. Testers can explore other options provided by ChromeOptions to customize the behavior further.
- Ensure that the version of ChromeDriver that is used is compatible with the Chrome browser version.
- The general approach is similar if using a different programming language. Set up the options tailored for the headless mode for the corresponding WebDriver.
- This configuration allows testers to run Selenium tests in a headless Chrome browser, which is useful for automated testing in environments where a graphical interface is not required.
Conclusion
In conclusion, headless testing with Selenium ChromeDriver has transformed web-based testing, automation, and data collecting by providing a robust and efficient alternative to standard browser interactions. Furthermore, using several proxy types can greatly expand Selenium’s headless browser capabilities, allowing for load balancing, improved security testing, and more diversified testing.
Headless testing is significant because it allows for quicker and more efficient testing, supports CI/CD workflows, enables testing across various platforms and environments, and can decrease testing and development costs and resources. Ultimately, the choice to choose the headless mode for web testing or development is based on task-specific requirements and the balance between advantages and drawbacks.
