Best Practices for Selenium Testing 

Selenium is a framework for testing web applications. Along with testing web applications, Selenium testing is also widely used to perform automation tasks and scrape data from websites efficiently. It supports multiple programming languages, including Java, Python, c-sharp, and Ruby. It is as close to human user behavior as one can get. It’s the perfect tool for testing the web application flow from start to finish. 

This article is designed to serve as a comprehensive guide on best practices for using Selenium effectively in web application testing. 

Why Selenium over other Tools? 

 There are several reasons to use Selenium over other test automation tools out there: 

  • It provides multi-browser flexibility. 
  • It is open source. 
  • It is easy to use and integrate. 
  • It supports parallel testing. 
  • It is highly flexible. 
  • It works across different operating systems. 

Best Practices for Selenium Testing 

One of the main reasons selenium testing is so widely used across different platforms is the wide range of options it provides with tools and different libraries.  

With every increment in tool options, it is crucial to choose the right tool for the right job. To overcome this hurdle, we can follow some basic practices and patterns that make the whole selenium testing process more efficient and organized. 

Page object models 

The Page Objects design pattern abstracts the representation of a web page using a specialized domain-specific language. This abstraction conceals the underlying implementation details of the page. Tests use classes and methods to perform actions instead of directly interacting with the page elements. This design hides specifics like element IDs and provides a structured framework tailored to the application being tested. 

Using this design has numerous advantages. Some of them are: 

  1. DSL System: Using the Page Objects design, we create a system representing the application from a business perspective. Tests written with this system should be easy for stakeholders in that field to understand. For example, a test for an accounting system might use terminology specific to accounting, making the tests comprehensible to accountants, even if they might be complex for others. 
  2. Testing Behavior: Similar to Behavior-Driven Development (BDD), the Page Objects design helps test how the application should function using its specific domain language. This ensures that tests align closely with the expected behavior of the application. 

Running Selenium Tests on Real Devices 

Although multiple emulators are available online for Selenium testing across platforms, conducting tests on real devices yields significant advantages. 

Emulators are software programs that simulate device functionalities, often used for early-stage code testing in development. However, they may not cover all device and operating system combinations, posing challenges for QA teams aiming to test specific scenarios. 

Testing on real devices provides more accurate results by replicating real-world user conditions. This approach helps teams identify a wider range of bugs, leading to the development of a more robust application. 

Teams can utilize cloud-based platforms like LambdaTest, which offers a Cloud Selenium Grid. LambdaTest is an AI-powered test execution platform that lets you test websites in different browsers with over 3000+ real devices, browsers, and OS combinations. 

Test Independence 

Writing every complex test code is a work of art in itself. Still, it is very important to ensure that these different test codes don’t interfere with the running of other tests and give accurate results without relying on other test outcomes or their previous state data.  

This will not only slow down the whole process but will also increase the complexity of the code, making its readability bad as well. It is always better to create separate test cases, which also gives organized and efficient work. When test cases are designed in such a way that they are independent, they are easier to debug and maintain. 

Stabilizing the Tests 

To maintain the reliability and effectiveness of selenium testing, some crucial key points should be considered while working on the tests or test codes. A few of these key points are: 

  • Maintaining a stable test suite. 
  • Discarding bad code changes. 
  • Regular Maintenance. 
  • Use of explicit waits. 
  • Reporting of failures. 

Generating Application State 

Selenium testing consists of multiple steps in testing any web application, as every feature and corner of the web application is tested a number of times until there are no glitches or bugs. One of the most important and initial steps of these tests is user authentication, which is needed to get the service of any web application.  

Now, generating an application state will make sure that this user authentication does not come in a way every time the tests are being run; not only this, but through it, tests can also be directly navigated to a certain page or if filling some form is a part of the test it can also be done by programming the data in selenium.  

However, sometimes API calls might be needed to fetch some information or set up data before moving further in the test; libraries like ‘request’ in Python can be used for the API calls. 

Domain-specific language 

A domain-specific language(DSL) in Selenium testing is a customized language designed to fill the gap between the testers and the users of the web application. DSL suggests that rather than using technical terms, the web application should contain more friendly terms, which would make the user experience better and more stable.  

It also makes it easier for non-technical users to understand and contribute to test automation efficiently. It also allows the developers to easily collaborate with testers and business analysts without getting into all the complex technical steps. 

DSL can be implemented in selenium testing in two simple steps: 

  1. Defining the Domain-specific language commands: This is done by creating a class and encapsulating the commands within. 
  2. Using the Domain-specific language commands in the test scripts.  

Advantages of using Domain-specific language: 

  • Abstracts complexity. 
  • Improves the readability of the test programs. 
  • Facilitates Communication. 
  • Promote Reusability. 

Mock external services 

The main reason for all the testing is to ensure the web application operates efficiently under various conditions while maintaining isolation from third-party services for security reasons. To achieve this, simulations of different external circumstances are created.  

These simulations place the web application in scenarios where various types of APIs, large databases, and other services are utilized, depending on the specific requirements of the web application. 

Some of the benefits of these simulations are: 

  • Increases the stability of the web application. 
  • Improves its reliability. 
  • Tests the web application in isolation. 
  • Makes the testing process independent of external services. 

Improved reporting 

Selenium provides a wide range of tools and libraries, but it lacks a built-in reporting system or service. However, in any web application testing, catching the issues quickly and communicating the result is crucial, and unit test framework integrations are used for that.  

These unit test frameworks support built-in reporting efficiently and provide an organized result that can be parsed by CI/CD(Continuous integration and continuous delivery/deployment) tools or other custom reporting systems. Along with the test frameworks, some other tools and practices are used. A few of them are: 

  • Logging and Logging libraries. 
  • Custom HTML reports. 
  • Capturing screenshots and videos of failures. 
  • Email and Slack notifications. 
  • Visualization of test metrics. 

Avoid Sharing State 

Sharing state simply explains the circumstance where a particular test case is dependent on some other test case outcome; this not only slows down the testing process but also jeopardizes the isolation of the web application while testing. Now, to ensure the independence of the testing process and reliability, some of the best practices that are considered are: 

  1. Isolate Test Cases: Each test case should be independent of others, with no dependencies on previous test outcomes. This ensures that failures or changes in one test case do not affect others. 
  2. Session Management: Manage sessions and state carefully during testing to prevent contamination between test cases. Clearing cookies, resetting databases, or using sandbox environments can help maintain isolation. 
  3. Parallel Execution of Test Cases: Running test cases in parallel reduces overall testing time and minimizes dependencies between tests. This approach can improve efficiency and scalability in testing. 
  4. Use of Fresh Test Data: Ensure that test data is fresh and isolated for each test run. Avoid reusing data between tests to prevent unintended dependencies or side effects. 

Fresh Browser per Test 

Every test case should have a clean environment in which to simulate, as it ensures the isolation and reliability of the testing without any cross-interference. Some of the browsers start each test with a clean environment by default. For example: 

It can be easily practiced in a few simple steps: 

  1. Initialize the new browser instance using the setup method before each test. 
  2. Ensure proper browser cleanup using the teardown method after each test. 
  3. Use of TestNG annotations. 

Note: Make sure the programmed tests are compatible with the browser version being used for Selenium testing and properly configured. 

Use of the Right Locators 

In selenium testing, locators basically serve as a pointer to web elements of any web application, such as links, checkboxes, and text fields. They also control automation, such as clicking a certain button, typing, or reading some data. Selenium provides and supports multiple kinds of locators, some of which are: 

  •    ID Locator: 

    It uses the value of the HTML id attribute to find the element. 

  •    Name Locator: 

   It uses the value of the HTML name attribute to find the element. 

  •    Class Name Locator: 

   It uses the value of the HTML class attribute to find the element. 

  •    Tag Name Locator: 

    It uses the HTML tag name to find the element. 

  •    Link Text Locator: 

    It uses the exact text of a link to find the element. 

  •    CSS Selector Locator: 

    It uses CSS selectors to find the element. This method is very powerful and    

    flexible. 

  •    Partial Link Text Locator: 

   It uses a portion of the link text to find the element. 

  •    XPath Locator: 

   It uses XPath expressions to find the element. This is the most powerful locator  

   method, but it can also be the most complex. 

Note: The above example codes are in Python Programming language. 

Use of Fluent APIs 

In Selenium testing, chaining is often used to ensure the sequence of multiple methods calling for a single statement does not get off track; this also binds the multiple methods together. To make this effectively possible, multiple APIs are used to program the test scripts. These APIs are often used along with the Page Object Model (POM) pattern for efficient results.

Some of the benefits of using these fluent APIs are: 

  • Readability 
  • Maintainability 
  • Reusability 

To use APIs in selenium testing with the Page Object Model, some steps are followed: 

  1. Defining a Page Object with Fluent API Method. 
  2. Using the Page Object in Test Script. 
  3. Improve Page Object with Assertions. 
  4. Using Enhanced Page Object in Test Script. 

Conclusion     

In conclusion, we can say that adopting simple yet very crucial practices in selenium testing not only makes the whole testing process way simpler but also creates a robust, efficient, and structured test simulation framework. It provides a regular update and makes the most of all the tools available for the job. This approach makes sure that automated test cases provide results with satisfactory accuracy and are reliable and maintainable, overall contributing to the quality and stability of the selenium testing of any web application.