What is Selenium Testing? A Complete Guide

In this article, we will focus on providing an introduction to Selenium that will provide you with a fundamental grasp of the Selenium tool suite, the importance of the tool as a bigger picture in software testing services, and criteria to assist you in determining if it meets your requirements as a tester or QA team.

Let us commence!

1. What is Selenium Automation Testing?

Selenium is an open-source framework that allows testing web applications over multiple devices and systems. Various computing languages, such as Java, C#, and Python can be used to construct Selenium Automated Testing. This testing refers to tests conducted with the Selenium testing tool.

Selenium Technology is not an individual tool that is used for a single purpose, but rather a series of tools, with each component catering to a distinct Selenium automation testing requirement of a business, such as:

  1. Selenium Integrated Development Environment (IDE)
  2. Selenium Remote Control (RC)
  3. Selenium WebDriver
  4. Selenium Grid

The new automation testing tool addition is Selenium 2 which comprises both Selenium RC and Selenium WebDriver integrated into a common architecture. In addition, Selenium 1 relates to Selenium RC.

2. Selenium Testing Tools

Selenium Testing Tools

2.1 Selenium IDE

Selenium IDE is a ‘record and playback tool’ that enables the creation and modification of test scenarios and sets.

Integrated Development Environment (IDE) is a Firefox extension designed to establish and perform test cases. It allows you to construct test cases by capturing your internet activities. Your activities are “translated” into Selenium-specific stages. These stages can then be translated into computer programming such as Java, Python, and Ruby, for subsequent execution. The final output is the whole test program in your chosen language.

It has the disadvantage of being mostly intended for prototyping and syntax. Among the limitations include the inability to script using conventional programming languages, the inability to test interactive online apps, and the inability to input data to facilitate data-driven testing.

2.2 Selenium WebDriver

Selenium WebDriver, commonly referred to as Selenium 2.0, performs test scripts using web-dependent services. It comprises:

2.2.1 API (Application Programming Interface)

It uses binders and converts test scripts written in Ruby, Java, Python, or C# to Selenese.

2.2.2 Library 

It is the repository for the API and coding-related bindings. The key end-user bindings maintained by the project plan are Selenium Java, Selenium Ruby, Selenium Dotnet, Selenium Python, and Selenium JavaScript (Node). 

2.2.3 Driver 

Exe file component that launches the test script in a web server instance. Google develop and maintain Chromedriver for Selenium to provide testing on Chrome.

2.2.4 Framework 

Integration modules for human or computer language test tools, such as Selenium with Cucumber and Selenium with TestNG.

2.3 Selenium Grid

The Selenium Grid can reduce test execution time by simultaneously performing many test scenarios on any range of distant devices. It is known as parallel testing. 

It is an intelligent service that delivers test inputs to distant web sessions. In addition to the user-side/tester test suite, this requires the following classified into two major categories: 

2.3.1 The “Hub” (the server): 

Recognizes accessibility calls from the client WebDriver and sends JSON test orders to remote drivers on ‘nodes’ that have been authorized.

2.3.2  ‘Node’ (remote device):

It includes a local operating system, web pages, and remoteWebDriver. 

WebDriver-client utilizes remoteWebDriver to conduct the test on a mobile host. RemoteWebDriver is similar to WebDriver; other than that, it consists of two factors: User (the test code) and Host (which performs the test remotely).

In the test script, you provide the “desired capabilities” (mobile, framework, website, etc.) of the execution node. The Hub gets this code, searches the listed nodes for the one that meets the specified characteristics, and sends the test for performance to that node. 

Establishing the Selenium Grid is very simple, but growing, customizing, and sustaining its integrity may be resource-intensive. Adopt it only after thoughtful thinking. 

2.4 Selenium Remote Control (Selenium RC)

Due to the limits enforced by the same source regulation, testers utilizing Selenium Core would have to set up the entire program undergoing testing and the web host on their personal PCs. Therefore, fellow Thought Works developer, Paul Hammant, planned to install a web server that acts as an HTTP proxy to “fool” the browsers into thinking that Selenium Core and the web apps getting run originate from the same address. This technology is referred to as Selenium 1 or Selenium Remote Control. 

3. Choose the Right Selenium Tool For Testing

3.1 Selenium IDE

  • Master test automation with Selenium fundamentals, using Selenese actions like write, read, clickAndWait, assertion, and verification.
  • Locators include identity, title, XPath, and CSS selector.
  • Customized JavaScript code execution with runScript.
  • Sending test cases in many file forms.
  • Construct tests with minimal or no coding experience.
  • To produce fundamental test sets that can be transferred to Selenium RC or Selenium WebDriver.
  • To test a web app just using Firefox and Chrome.

3.2 Selenium RC

  • To create a test employing a more descriptive language than Selenese.
  • To execute your test across several web browsers (excluding HtmlUnit) and OS systems.
  • Utilizing Selenium Grid to run your testing across various settings.
  • To test the program on a new browser with JavaScript functionality.
  • To test web apps using AJAX-based complicated scenarios.

3.3 Selenium WebDriver

  • For utilizing a specific computer language while developing a test case.
  • To evaluate apps with extensive AJAX-based functionality.
  • To run tests within the HtmlUnit browser.
  • For producing personalized test results.

3.4 Selenium Grid

  • To concurrently execute the Selenium RC scripts in many browsers and OS conditions.
  • To execute a large test suite that must finish as quickly as feasible.

4. Why Do We Need Selenium Testing?

Consider this case for manual testing: Verifying that the registration page for the web application verifies key inputs and correctly creates a user with the most recent editions of browsers on Windows.

Suppose that the registration page contains the following data input: account, contact information, and passcode. The tester will receive a Windows desktop and execute the following tasks on the most recent editions of Chrome and Firefox:

  • Insert the address and signup.
  • Enter correct characters in each section. 
  • Verify that the input strings were checked against relevant regular expressions and any data entries already existing. 
  • Insert “valid” text in each section; then press Sign Up. 
  • Determine if the “Welcome, “username”‘ page was shown. 
  • Confirm if a new userID was generated in the database server for ‘log in’. 
  • Sign the test pass if it was successful and “failed” if the login functionality refused at any point throughout the test.

This is a really simple system test. In the actual scenario, testers will likely examine all client processes on site for defects on as many operating systems and browser combinations as necessary to achieve performance test compatible criteria.

Based on the quantity of human testers (and the depth of the tests), it might take anything from days to months to ensure that the web application is completely working. 

Advanced developers and business teams may not have that much time to devote to testing, but they also cannot forgo rigorous testing in a rush to deploy. This is why they use Selenium-powered automation to boost their analysis. 

5. Which Type of Testing Can be Automated With Selenium?

Selenium may be used to automate several forms of testing. Let’s briefly explore the many methods of testing for selenium projects. 

5.1 Unit Testing

When a developer fixes a defect or adds a new function to a portion of a web app, he or she will do this form of testing in a selenium project. Unit testing might be difficult if experts are tasked with implementing several code modifications across multiple application components. 

Unit testing tools tailored for individual programming languages, like NUnit for Python, JUnit for Java etc. exist to streamline the unit test cases. Selenium is simply interoperable with these technologies, enabling developers to verify the unit testing over numerous os and browser configurations. 

5.2 System Testing or Black-box Testing

In the context of system testing or black-box testing, it is the responsibility of the testers to verify the system’s adherence to specified criteria. They must do end-to-end testing of the component’s functioning. During this assessment, the testers do not perform any previous tests, nor do they have any knowledge of the provided code’s background. 

In addition, a QA engineer must develop a script that verifies all of the program’s capabilities. Selenium enables testers to execute black-box testing programs, which frees up resources for experts to generate and consider more novel testing cases. 

5.3 Integration Testing

Furthermore, professionals of the QA team undertake a series of tasks to check that all the software’s components function correctly, both individually and when integrated. They guarantee that the components generate identical outcomes following integration. This occurs when you combine two or even more app components to exhibit a single feature. 

Using Selenium Automation Testing, developers can simply do comprehensive compatibility testing for each software release. This facilitates the evaluation of the functioning and characteristics of the web application’s numerous components.

5.4 End-to-end Testing

Technical staff performs end-to-end testing of online apps from the viewpoint of users. The QA engineers must develop a collection of test cases to ensure that the web service operates properly at several places. End-to-end testing requires a significant deal of time, particularly if the online application contains various elements and pages that must be evaluated on different devices, platforms, and operating systems.

Selenium Automation simplifies this procedure by enabling experts to automate the web through parallel testing. In addition, Selenium Automation enables testers to generate statistics on performance metrics, test case conditions, etc.

5.5 Regression Testing

Regression testing enables programmers to evaluate the end-to-end functioning of a software’s web page as the program is transferred from one test setting to the next. This is to ensure that the additional programming does not interfere with the web application’s current functioning. This is among the primary reasons why experts do regression testing following each release cycle.

Additionally, regression testing guarantees that the present application continues to function properly following the addition of new features. Sadly, it is a tedious procedure since specialists must test the whole website, even if only a minor update has been made. Selenium enables the automation of continual regression testing, saving experts a great deal of time.

5.6 Performance and Load Testing

End users are only concerned with the functionality of the online service. The quality assurance team is accountable for conducting numerous tests to see if the application meets the requirements and objectives of the end-users, as determined by the sponsors. Instead of individually executing the web application on multiple different permutations of operating systems and web browsers, experts can automate the procedures using Selenium to create the application’s effectiveness matrix.

5.7 Automated Browser Testing

As previously noted, cross-browser testing is the fundamental reason for Selenium’s success. Selenium serves all important browsers as well as a Selenium Grid enables you to execute browser automation to analyze your web application across many browsers concurrently.

5.8 Monkey Testing

In Monkey testing, they attempt to damage the system by feeding it unpredictable information. From the viewpoint of the end user, the command might be whatever, including clicking, scrolling, or a fake text string.

Selenium allows building multiple test scripts to perform monkey testing. For instance, you may create software that produces random clicks around a webpage by continually searching for web locators.

6. Why is Selenium Important?

Teams are afraid to release a product too quickly. SDLC often includes rigorous testing whenever a method is manual. Based on the scale of the testing crew, the duration of the procedure might range from a few weeks to several months. No business can tolerate the waste that results from devoting an excessive amount of energy to construction. If you want to accelerate the workflow, Selenium testing automation is the technique to approach. Here are the principal advantages of utilizing Selenium.

6.1 Faster Cross Browser Testing With Selenium

Subscribers can get their hands on online apps choosing any internet browser of one‘s wish. Therefore, it is essential to guarantee that a website is functional with several browsers. Thus, you can guarantee that your consumers always encounter a flawless UI, irrespective of the browser they employ. Cross-browser testing is the practice of evaluating your web service across many platforms. It may be a nightmare for human testers, who may have to test across dozens of browsers each moment when a modification is sent to their online application. Nevertheless, Selenium enables the automation of browser testing.

Selenium WebDriver can automate browsers, including Internet Explorer, Mozilla Firefox, Opera, Safari, Google Chrome, and Microsoft Edge.. What else could one want than a solitary test automation framework that ensures connection with all of them?

Browser testing using Selenium has simplified the lives of web testers worldwide.

6.2 Supports Different Programming Languages

This testing offers multiple programming languages, allowing any tester to grasp the test automation framework with relative simplicity.

What computer languages is this WebDriver compatible with? While you may do web testing with Selenium using virtually any computer language, becoming famous has its advantages. The original Selenium test scripts encourage Java, JavaScript, C#, Python, PHP, and Ruby interfaces.

Additionally, Selenium accepts several operating systems. Selenium supports various operating systems including Windows, Linux, macOS, and Solaris. Thus, you may rigorously evaluate your software platform by running it across combinations of browsers and operating systems.

6.3 Selenium Can Be Integrated With CI/CD Pipelines

Continuous Integrating and delivery need the quick and regular deployment of new development updates. Consider being responsible for manually guaranteeing the cross-browser suitability of your web application after each build passes throughout the CI/CD pipelines. Not forgetting the possibility of human mistakes when doing the task. With Selenium, there is a superior method!

Leveraging the Selenium browser automation technology, the developer does not have to rely upon cycles to complete. CI engines tell every team-mate about setup, environment, code refactoring, and failures. This allows the team to detect installation errors early on, if any.

Recurring efficiency, functionality, and suitability testing can be aided by Selenium automation. It also promotes rapid debugging by providing engineers with near-immediate feedback.

6.4 Selenium WebDriver Increases an Agile Tester’s Productivity

Agile is a methodology that emphasizes the continual improvement of a product by splitting the whole development effort into tiny sprints. During every certain period of cycle, a fresh element is introduced to the program via a product cycle. After each iteration, testing is undertaken to guarantee that the web application or website is completely functional. This allows for continual input and the elimination of issues throughout the earliest stages. Nevertheless, it might be difficult for rapid testing to evaluate new demands while still monitoring regression bugs.

Selenium controls browser-based content, enabling agile testers to automate monotonous test scripts and generate more rigorous test cases. The Selenium framework accelerates test running and increases overall testing performance.

6.5 Widely Used Testing Automation Tool

There are vast amounts of open-source applications accessible online. Nevertheless, before integrating any open-source technology into the operations, one must evaluate its legitimacy. 

Since 2004, the Selenium Initiative has been consistently handled, and the Selenium technology has been enhanced. Additionally, the Selenium testing tool has a large user population, so if you get confused with anything, you can ask for assistance. With the aid of the Selenium ecosystem, Selenium courses, journals, and online forums, it may be quickly resolved.

7. Conclusion

In this blog post, we covered an advanced guide on Selenium. We gained an understanding of Selenium testing, the Selenium tool suite, the significance of automated testing with Selenium against QTP, and how to pick the appropriate Selenium tool for your purposes. If you consider this blog to be interesting, please comment!

Itesh Sharma

Itesh Sharma is core member of Sales Department at TatvaSoft. He has got more than 6 years of experience in handling the task related to Customer Management and Project Management. Apart from his profession he also has keen interest in sharing the insight on different methodologies of software development.


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    1. Sonit Desai

      This article provides a comprehensive overview of Selenium testing. It gives a detailed understanding of how Selenium can help to improve the quality of your software and save you time and money. I especially liked the section on Selenium Grid, which I didn't know much about earlier. I would definitely recommend this article to anyone who is learning more about Selenium testing.

    2. Krisha

      Thank you for sharing such useful information on Selenium that has helped me with my project on Selenium certification and training. I am also looking forward to reading another article on Selenium from you.