Selenium Automation Testing | Top Benefits & Challenges

Selenium is among the first choices when Agile teams decide to automate their testing. However, is it the best approach? Check out here.

What is Selenium?

Selenium is an open-source Automated Testing tool which provides a single interface to help you write test scripts in programming languages like Java, JavaScript, Python, Ruby, etc. to test web-based applications.

Components of Selenium 

Selenium has 4 components:

• Selenium IDE
• Selenium RC
• Selenium WebDriver
• Selenium Grid

Selenium IDE

Selenium Integrated Development Environment is a Chrome and Firefox plugin that can log interactions in the browser and generate its code in programming languages mentioned above, as well as Selenese which is Selenium’s own scripting language (yes, Selenium has its own scripting language!). Read more on – Selenium IDE

Selenium RC

Selenium Remote Control, also known as Selenium 1, was the first tool of Selenium Suite. Selenium RC is a server, written in Java, that accepts commands for the browser via HTTP. All the browsers which support JavaScript can be automated using Selenium RC.

In Selenium RC there is a manual process called Selenium Server which acts as a middleman between the code and the browser, and it is mandatory to start before the execution. The commands (API’s) are sent to Server which interprets the command and converts it into JavaScript and then JavaScript is injected to the browser. After that, the browser executes the JavaScript and responds to a Server, which again interprets the command and returns the code to the respective language.

Selenium WebDriver

Selenium WebDriver, also known as a Selenium 2.0, is the most important tool of the Selenium Suite. Selenium WebDriver formed as a Selenium RC upgrade, and it does not require any manual process like Selenium Server, instead, there is direct communication between code and browser.

Selenium WebDriver consists of:

• API – Application Programming Interface. Ports test scripts written in Ruby, Java, Python, etc. to Selenese (Selenium’s own scripting language), through bindings.
• Library houses the API and language-specific bindings. Although plenty of third-party bindings exist to support different programming languages, the core client-side bindings supported by the main project are: Selenium Java (as selenium jar files), Selenium Ruby, Selenium dotnet (or Selenium C#, available as .dll files), Selenium Python, and Selenium JavaScript (Node).
• Driver – Executable module that opens up a browser instance and runs the test script.
• Framework – Support libraries for integration with natural or programming language test frameworks, like Selenium with Cucumber or Selenium with TestNG.

The way Selenium WebDriver works:

The WebDriver protocol has a local end named client which sends the commands (test scripts) to a browser-specific driver. The driver then executes these commands on its browser instance. So, if the test script calls for execution on Chrome and Firefox, the ChromeDriver will execute the test on Chrome; the GeckoDriver will execute the test on Firefox.

Note: Test scripts execute only when the WebDriver’s client and browser/driver are connected. It doesn’t have to be on the same device. However, to enable test execution on multiple remote drivers, you need RemoteWebDriver and the Grid.

Selenium Grid

Selenium Grid is the last component of the Selenium Suite and it is used for the parallel testing or distributive testing. It allows us to execute test scripts on different machines at the same time.

The Architecture of Selenium Grid

In Grid one of the systems is created as Hub. Hub works as a central point controlling all the nodes, it accepts access requests from WebDriver client. Nodes are an actual machine on which execution is done and contains a native OS, browsers and RemoteWebDriver.

The way Selenium Grid works

WebDriver-client executes the test on a faraway device through RemoteWebDriver. RemoteWebDriver is like a regular WebDriver, except its two components are the Client (your test script) and Server (a Java servlet that actually executes the test on the remote device).

In your test script, you define ‘desired capabilities’ (device, platform, browser, etc.) of the node where the test will execute. The Hub receives test script, runs through the registered nodes to find the one that matches the desired capabilities, and assigns the test to it for execution.

When it comes to real test automation, the ideal candidates are your regression test cases that you would usually execute to ascertain the overall stability of your application. See the detailed guide on how to automate your regression test cases using Selenium.

History of Selenium

The story of Selenium started in 2004 when the tool first became available for commercial use. Over time, it has evolved to include Selenium IDE, RC, and other components that make this tool the go-to test automation tool of today’s time.

Importance of Selenium Automation Testing

When you work in software testing, you know that the manual approach to validating features is an extended and long-drawn process. It demands continuous monitoring through human-based intervention. Naturally, adopting automation techniques in such scenarios is the right way to go.

One way to do so is by scripting tests in Selenium, which comes with a huge community of users and supports multiple languages to create the tests.

It further comes equipped with many testing abilities, such as:

• Browser Support: Selenium Automation testing offers extensive browser support across major browsers like Chrome, Firefox, Safari, and Edge to promote cross-browser compatibility.
• Parallel Testing: Selenium not only saves time by automating tests but also enables parallel testing across different environments, which significantly accelerates feedback loops.
• Reusable Test Scripts: With Selenium you can create reusable test scripts to use across multiple test cases and projects in order to reduce effort in writing and maintaining scripts.
• UX Reporting: Selenium integrates with various reporting tools to provide detailed UX reports that offer insight into test execution, product failures, and performance issues.
• Scalability: The framework of Selenium is largely popular for handling large-scale test automation projects with ease across multiple machines and environments.
• Community and Documentation: Selenium boasts a large and active community that regularly contributes to sharing knowledge through updated documentation, tutorials, and forums. The strong community support makes Selenium a reliable and evolving tool for test automation.
• CI/CD Integrations: Selenium integrates with CI/CD tools like Jenkins, Travis CI, and CircleCI to automate test execution as part of the development pipeline.

Different Types of Selenium Testing

Like any other testing tool, Selenium offers a wide range of testing options, including unit testing, functional testing, regression testing, and integration testing.

Unit Testing

While unit testing is typically performed with frameworks like JUnit or TestNG, it can also be done using Selenium. The tool can aid unit testing by validating web component functionality in isolation. 

For instance, testing a specific JavaScript function’s impact on a web element’s behavior using Selenium WebDriver. Read more on Web elements in Selenium

Functional Testing

Selenium excels at functional testing by automating user interactions with the web application by simulating real user scenarios, such as form submissions, navigation, and button clicks.

Regression Testing

For regression testing, Selenium comes out to be an ideal tool as it automatically re-runs the test case when any changes or updates are detected in the code. By doing so, the manual intervention is reduced, and the test case corresponding to the area of the changed code is executed to confirm that existing functionalities remain unaffected.

Integration Testing

Selenium can perform integration testing by automating interactions between different web modules or services. It tests the combined functionality of integrated components to ensure they work together as intended and the data flow between them is not affected.

As you could see, Selenium has pros and cons and depending on your type of software you should consider which approach is the best. After considering all, maybe Automated Testing would not be the best approach, and that is where Scriptless Automation Testing advent.

We will tell something more about the challenges in Selenium-based Automated testing, so you can better understand the difference between Automated Testing and Scriptless Test Automation.

Why Should You Use Real Devices for Automation Testing in Selenium?

After the testing phase is over, the software is handed over to the real users. Just because the testing yielded no unexpected results does not mean users won’t encounter them because users run the product under varying circumstances and situations.

That’s when using real devices for automation testing in Selenium comes to the rescue. It ensures that your tests accurately reflect real-world user conditions and provides authentic hardware and software environments to detect issues related to performance, compatibility, and user experience. Testing on real devices further ensures better reliability and confidence in test results.

Selenium Automation Testing Requirements

If you are a small business just starting out in the testing domain for your product or the client’s, the Selenium test automation approach could be expensive. However, the extent of this pricey deal will also depend on the browsers you are running your tests on and how many times you run them.

For instance, if you have a web application that needs to be validated for cross-browser compatibility, the requirements would include:

• Set up Webdriver and install relevant libraries.
• Get the latest versions of the browsers you want to run your tests on and configure their settings.
• Develop test scripts in your language.
• Set up a test environment and integrate the tests with a suitable framework, such as JUnit, TestNG (for Java), PyTest (for Python), or NUnit (for C#).
• Combine the tests with CI/CD tools to automate the cross-browser test execution.
• Finally, report the results using the reporting tools that are preferable to you.

Following these steps and keeping the tests and results updated can prove to be expensive and time-consuming. Yet the above approach includes the basic requirements for any Selenium-based testing.

Challenges Involved in Automated Testing

• Lack of quicker feedback: Scripts are written after the application is built and stabilized. Early feedback, which is essential for the reduction of the cost of quality in Agile development, is seldom available. Read more on the importance of Shift Left Testing.
• Substantial upfront investment: Huge upfront investments are necessary due to complex scripting environments and tools, and also for test infrastructure. Hence, we would need to hire and train skilled resources. The article Overcoming The Ramp-up Delay, Cost and Resources Required To Automate Testing explains about the test automation ecosystem.
• Change of focus: The prime objective of the testing team has moved from testing the functionality of the application to the technical development and execution of scripts.

Tips for Running Successful Selenium Tests

Making sure to follow certain techniques to write test cases and execute them will help you easily get the grasp of Selenium and receive better results.

• To start, create a small, simple test to verify the functionality of a certain feature.
• Keep the test concise and target the right components on the page or application you are testing.
• Use reliable locators like ID, name, or CSS selectors to ensure stable and maintainable tests.
• Utilize implicit and explicit waits to handle dynamic content and ensure elements are available before interacting with them.
• Use Page Object Model (POM) to organize and manage web elements and interactions.
• Integrate Selenium tests with CI/CD to automate and streamline the testing process.
• Keep the test code and results well-organized so that they can be monitored and followed up easily in the future.

Troubleshooting Common Issues with Selenium Tests

It can be challenging to troubleshoot issues with Selenium, but it is not impossible. By only following a few simple steps, you can overcome any difficulties faced while creating and executing tests in Selenium.

• Selenium Grid is a surefire way of troubleshooting Selenium issues. With Grid, you can run tests in parallel and identify performance and compatibility issues on different browsers and devices.
• Employ Selenium WebDriver to use its alert handling capabilities to accept or dismiss pop-ups. Additionally, Webdriver provides a feature to capture screenshots and videos that are useful in debugging the issues.
• Make sure to set up a test environment that closely matches the production environment. 
• Stay compliant with the security concerns of the application under test by using the Selenium Security Testing Framework to locate and resolve safety issues.

Read here about – Testsigma vs Selenium

How to Get Started with the Selenium Automation Testing Tool?

To get started with Selenium, you will first have to download and install Selenium WebDriver, a browser extension that connects with the browser on your system to support cross-browser testing. Once the driver is successfully installed, you can start creating the test cases.

To install Selenium, follow the below steps:

• Go to https://www.selenium.dev/ and click on the ‘Download’ option in the menu.
• Scroll down to the Selenium IDE option and select the browser for which you want to download.
• Add the extension to the browser and follow the instructions as mentioned.
• After the installation is done, start writing the test cases in the language of your choice.

Read more about how to use Selenium with Eclipse.

Future of Selenium Automation Testing

By seeing the growth of Selenium in the past decade, you can predict that the future of Selenium is promising.

Some of the things you can expect to see in time are:

• Integration of AI and Machine Learning into the platform for easier and more efficient test case creation.
• Enhanced Browser and OS Support beyond the current stack.
• In-built or better support for headless and mobile testing.
• Selenium Grid might become more efficient and user-friendly in running a high number of parallel tests without issues.
• More support for the latest CI/CD tools, development frameworks, and cloud-based testing platforms.
• Detailed and highly comprehensive reporting features and analytics tools within Selenium to provide deeper insights into test results.

Conclusion

In conclusion,  the key holdups in adopting traditional QA methods are the issues faced by functional and business teams in understanding automation scripts. Additional effort is required to make them available to non-technical users, leading to reduced collaboration between the functional specialists and automation teams.

One of the solutions to maximize the scalability of Automated Testing is Scriptless Test Automation. Scriptless Test Automation enables QA Engineer to automate test cases without coding, and any knowledge of it. It helps to achieve faster results and reduces the time expanded to understanding the code.

Now that you know about the basics of Selenium and are aware that scriptless test automation is an alternative to it that makes the test automation very easy, the next logical read for you would be: Selenium vs Scriptless Test Automation.

Read more : An alternative to Selenium for test automation in Continuous Delivery

Until then, sign up for a free trial of Testsigma, Scriptless Test Automation tool powered by NLP! Start writing complex automated tests in simple English.

Still in doubt? Read the detailed comparison between Testsigma and other tools.

Frequently Asked Questions

How is Selenium Testing Integral to CI/CD?

Automation testing is a key part of the CI/CD process. When it comes to Selenium-based automation testing, integrating it with CI/CD pipelines is crucial for achieving continuous quality assurance. It helps to automatically execute tests during each code commit, build, or deployment, ensuring immediate feedback on code changes. 

Another useful aspect of this integration is the ability to quickly identify and fix defects to maintain software stability and reduce the risk of introducing bugs. Automated Selenium tests enhance the efficiency of the CI/CD process by allowing frequent, reliable testing across various browsers and environments.

Selenium Limitations and Challenges

Top Limitations and Challenges in Selenium & Solution

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A Complete Guide to Selenium UI testing

Selenium IDE

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