What is Selenium?: Introduction to Selenium Testing

 

The process of Software Testing, if executed in a manual fashion, can be extremely time consuming and strenuous. So what if, we could automate the testing process? It would definitely make it more efficient and productive. This is your answer to what is Selenium as it is the tool which helps in automation of the testing process, resulting in the execution of Selenium Automation Testing.

This blog would provide you with a comprehensive understanding of what is Selenium, its advent as an open source automated testing tool, its benefits as well as shortcomings and much more.  Consequently, we will cover the following topics:

What is Selenium?

What is Software Testing?

Limitations of Manual Testing

Advent of Selenium Automation Tool

Selenium Suite of Tools

Selenium Uses: Its Advantages

Limitations of Selenium

Selenium Jobs

Conclusion

What is Selenium?

Selenium is a software testing tool which is free, open-sourced and is used for testing web applications across different platforms and browsers. The process of Selenium Automation Testing embodies a single interface and allows the user to write test scripts in different programming languages like Java, Python, C#, Ruby, Perl, PHP and NodeJS. It can only be used to test web applications and not desktop or mobile applications.

What is Software Testing?

Testing is undertaken in order to evaluate the performance, quality and dependability of a product, before it is finally released into the market. This software testing is done for web applications too. As a sizable mass of business operations have emerged as being completely internet based, testing has become indispensable. Consider a situation where you try to add an item to your online shopping cart, but you are simply not able to do so and you are continuously redirected to an error page. This might happen as a result of some bug in the backend code of the web application and this glitch might result in significant revenue loss for the e-commerce company. Hence, there is a need to test the code for avoiding such mishaps.

Limitations of Manual Testing

Manual testing is when the test is executed by Quality Assurance (QA) personnel by writing test cases. These cases are made to run manually for every transaction and their result (failure or success) is required to be recorded manually. Given such a scenario, the drawbacks of manual testing are as follows:

·         It is extremely time consuming

·         It is limited in scope and requires a tester at all times

·         There is a high chance of human error and the product quality happens to be low

·         All defects and test cases may not be detected

·         There is no support for performance and batch testing

The drawbacks of manual testing resulted in a shift in favor of automation testing and the Selenium Automation tool came into prominence. It involves the execution of test cases with the help of a tool, which could avoid manual interference.

Advent of Selenium Automation Tool

The Selenium Automation Tool evolved over the years with its different forms being developed in order to address the shortcomings of its predecessors, as they were subsequently noticed during Selenium Automated Testing. 

In discussing the development of Selenium in subsequent phases, it is important to understand an important concept (The Same Origin Policy Issue) which was the major reason for a shift from Selenium Core to Selenium RC. Selenium Core involved the interpretation and execution of Selenese commands through the built-in JavaScript interpreter of the browser. For example, if test.js is the JavaScript which is used by google.com, then this program was so designed, that it would be able to acquire access to pages like google.com/login or google.com/mail within the parent domain. However, it was not possible for the program to access pages from other domains, say yahoo.com, due to the same origin policy. This policy prohibited access to web elements from a domain which was different from the one where the JavaScript was launched. This compelled users to install local copies of Selenium Core as well as the web server which contained the web application, so that they belonged to the same domain.

This shortcoming of Selenium Core resulted in the birth of Selenium RC which sought to overcome the same origin policy problem by including a HTTP proxy server which could deceive the browser into believing that the web application and the test script came from the same source. 

Selenium Suite of Tools

The Selenium Automation software is not a single tool, but a suite of software, each of which serves a specific set of testing purpose for the organization. The tools are:

·         Selenium Integrated Development Environment (Selenium IDE)

·         Selenium Remote Control (Selenium RC)

·         Selenium WebDriver

·         Selenium Grid

Selenium IDE

 Features:

·         Selenium IDE was created by Shinya Kasatani of Japan as a ‘record and playback tool’ and was initially known as Selenium Recorder

·         Firefox plug-in which can be used to record and execute test cases

·         The interaction of the user with the browser is recorded and is made to create test cases

·         It was primarily created to accelerate the production of automation scripts

Pros:

·         Selenium IDE is simple, easy to install and user-friendly

·         Prior knowledge of programming language is not required, though basic knowledge of DOM and HTML is required

·         It supports extensions as well as appropriate reporting, debugging and scripting

·         It supports the export of recorded tests in different programming languages

Cons:

·         Selenium IDE is only available for Firefox and does not support data driven testing

·         Cannot test dynamic web applications and the execution of test cases is slow as compared to RC and WebDriver

·         It does not support conditional operations and iterations and is primarily designed to produce test prototypes

Selenium RC

Features:

·         Selenium RC was created by Paul Hammant in order to address the Same Origin Policy issue

·         Within the overall Selenium Project, Selenium RC was the first flagship testing tool

·         It allowed users to write test cases in their preferred language

·         Selenium RC 2.25.0 supported languages like Java, PHP, C, Ruby, Perl and Python

Pros:

·         It supports cross-browser testing, user preferred language and data driven testing

·         Supports conditional operations and iterations as well as new browsers

·         The execution speed is greater than IDE

Cons:

·         It involves a complicated installation procedure as compared to IDE

·         Prior knowledge of programming language is needed

·         Execution speed is slow as compared to WebDriver

·         API contains vague commands

Selenium WebDriver

Features:

·         Selenium WebDriver was created by Simon Stewart in 2006 for replacing Selenium RC

·         It provides an interface for creation as well as execution of test cases

·         It is possible to identify web page elements through the test cases and take appropriate action

·         In 2008, Selenium WebDriver was merged with Selenium RC to create Selenium 2

·         The user created script directly interacts with the browser and since each browser has its own WebDriver, it helps in the interpretation of the script

Pros:

·         It is quite easy to install Selenium WebDriver as compared to Selenium RC

·         It provides realistic browser interaction

·         Direct communication with browser with no separate component needed

·         In case of Selenium Webdriver, the execution time is faster as compared to Selenium IDE or Selenium RC

·         Testing is possible on multiple platforms

Cons:

·         Complicated installation as compared to IDE

·         Selenium WebDriver entails prior knowledge of programming language

·         Does not immediately support new browsers and there is no procedure to track runtime messages

·         Selenium WebDriver does not allow for image testing

Selenium Grid

Features:

·         Selenium Grid was created by Patrick Lightboy with the objective of lessening the execution time of test cases

·         It is used in combination with RC for the remote execution of test cases

·         Selenium Grid makes use of the Hub-Node design which helps in simultaneous execution of more than one test case on different machines which happen to be remotely located

·         There is one master system which is the hub and it controls the other child systems which are the nodes

Pros:

·         Facilitates parallel execution of test cases on different browsers

·         Selenium Grid offers tools which can help in the identification of failures and providing for new test execution

·         It helps in capturing screenshots of browsers at different points of execution of the test case

Cons:

·         It is possible to execute the code only on the local machine where the cases are launched

·         The remote machines are simply recipients of browser control commands

·         The initial operation of parallel testing requires significant amount of effort and time

Selenium Uses: Its Advantages

1.      Selenium Automation Tool is an open-source testing framework which is available free of cost. This makes it highly attractive as compared to its alternatives which generally come with a licensing price

2.      Selenium supports text scripts written in a wide range of programming languages: Python, Java, Perl, Ruby, PHP and C#

3.      It has a proven track record of accurate results, making it highly reliable

4.      Selenium facilitates execution of test cases on more than one operating system like Android, Windows, iOS, Linux and Mac

5.      Selenium Automation Testing can be carried out on multiple web browsers like Chrome, Opera, Safari, Internet Explorer (IE) and Firefox

6.      It allows for parallel test execution and has a huge community support

7.      Selenium provides for integration with JUnit and TestNG which helps in the generation and management of test cases

8.      Continuous testing is possible through the integration of Selenium with Maven Jenkins and Docker

Limitations of Selenium

1.      One major drawback of Selenium is that it can only be used to test web applications and is not suitable for testing mobile or desktop software applications

2.      There is no assured user support, apart from customer communities

3.      It cannot acquire access to web elements detected to be outside the web application which is under test

4.      Selenium Automation Testing cannot be used for image testing or data-driven testing independently. These are only possible with the integration of additional tools

5.      It requires prior knowledge of programming language to write tests

Selenium Jobs

Selenium as a career can be an extremely wise choice since the future holds considerable prospects for Selenium test automation engineers. As a Selenium WebDriver professional, you can think of Selenium job roles such as:

1.      Selenium Tester

2.      Selenium Quality Engineer – Automation

3.      Selenium Automation Engineer

4.      Selenium Test Analyst

5.      Java Selenium Automation Engineer

6.      Software Development Test Engineer

7.      Senior QA Automation Engineer

The average salary of a person engaged in a Selenium Tester Job in U.S. is $97,500 per annum. It falls in the range of $80,925 to $120,510. Similarly, a Software Test Engineer can expect an average salary of $100,971; $98,898 for Senior Quality Assurance Analyst; $89,657 for Automation Engineer and $93,606 for Senior Quality Assurance Tester.

If you wish to master the Selenium Automation Tool and strive to be a Software Development Engineer in Test (SDET); Syntax Technologies.

Conclusion

Automation is bound to rule production activities in the future. It is held to propel efficiency as well as guarantee ROI. Given so, Selenium is bound to remain the tool of choice. It may have its own disadvantages; however, its benefits overshadow other tools, predominantly in three specific areas: cost, flexibility and parallel testing.