Selenium is a very well-known open-source software suite, mainly used for testing web browsers and web applications by automating some processes. It comes with a set of tools and libraries that allow developers or testers to automate some functions related to web browsers and web applications.
- Selenium also supports different renowned Programming languages like Java, Python, C#, Ruby, etc. so that the developers can focus on the testing part and not think about learning a new language with which they are not comfortable.
- Testers can automate processes like clicking a link, opening new tabs, closing tabs, pressing any buttons, etc. that a normal user does with the browser.
Selenium Tool suite consists of 4 major components (one of them is now deprecated). We will look into them one by one in detail.
Selenium Tool Suite
- Selenium IDE (Integrated Development Environment)
- Selenium Remote Control (RC)
- Selenium WebDriver
- Selenium Grid
1. Selenium IDE (Integrated Development Environment)
Selenium IDE is a web browser extension that is available to install for most of the renowned browsers. It lets the testers record their interactions with the browser or web application and store them internally to prepare a test case. Then those test cases can be used by others, or the tester or developer can export those test cases into their preferred programming language, such as Java, Python, C#, Ruby, JavaScript, etc.
Benefits of Selenium IDE:
- User-Friendly, Interface: One of the most preferred advantages of the Selenium IDE is that it has a very user-friendly interface. It helps those who are not familiar with any programming language or are beginners to create and execute test cases based on the recorded automation.
- Record and Playback: Testers can record their interaction with the browser and the elements of the web page and play them later, allowing them to create easier test cases without doing much work.
- Cross-Browser Compatibility and Exporting the Script: The scripts stored/recorded in the IDE can be exported into different browsers or run in them. There is no need to make any changes to them rather than just import and export. Also, the testers can convert those test scripts into their preferred programming language if necessary.
Limitations of Selenium IDE:
- Functionality is Limited: One of the main drawbacks of the Selenium IDE is that its functionality is limited as compared to other Selenium tools.
- Dynamic Elements are not supported large-scalePlatform Theirlarge-scale: Selenium IDE might face some issues while handling Dynamic Elements or any complex web element.
- Not compatible with Non-Web Applications: Selenium IDE can only test web applications.
- Lack of Framework Support: The Selenium IDE can’t create test automation frameworks, which are essential for large-scale testing.
2. Selenium WebDriver
Selenium WebDriver is the heart and soul of the Selenium Tool Suite. It provides the testers or developers with a programming interface using which they can create test cases using different programming languages and test them by interacting with various web elements.
- Various renowned programming languages like Java, Python, Ruby, C#, JavaScript, etc. Using WebDriver, developers can write their automation test scripts using the programming language of their choice and then test those scripts with various web elements or browsers.
- The code written using WebDriver can directly communicate with the browser, so it is easy to manipulate web elements or automate the process.
- It can also work with most of the renowned browsers like Google Chrome, Firefox, Safari, Microsoft Edge, etc.
Benefits of Selenium WebDriver:
- Advanced Automation Capabilities: As the Selenium WebDriver provides the developers/testers a programming interface that allows them to write code, de i.e. automation scripts, the developers can develop way more sophisticated automation scripts as they have full control over them. Programming languages like Java, Python, C#, JavaScript, Ruby, etc. are available to write automation scripts.
- Cross-Browser and Platform Support: WebDriver supports most of the renowned web browsers and platforms (Windows, Mac) so it is easy for the developers to execute their automation scripts without thinking about compatibility.
- Improved Performance: As the code written in WebDriver can directly be executed in the web browser, the direct execution makes faster test execution and improved performance as compared to IDE.
- Flexibility: WebDriver is more flexible because everything is under the control of the developer/tester. They can write as many test cases as they want, or manipulate the web driver as they want.
- Language Support: WebDriver supports a variety of programming languages for the developers to use to write test scripts manually.
Limitations of Selenium WebDriver:
- Requires Programming Knowledge: To use Selenium WebDriver and create test scripts manually, the developers/testers need to know any of the supported programming languages. Due to this those who are not from a Technical Background find it difficult to use it.
- Complex Setup Process: Setting up the Selenium WebDriver is also a rigorous process as it comes with various extra drivers or browsers.
- Extra Maintenance Cost: As WebDriver provides an entire coding interface, developers/testers using that might need to debug and maintain their code so that they can use it later. This causes an overhead cost that should be borne by them.
- Browser Compatibility: Although browser compatibility might be the most useful and important feature of WebDriver, the developer/tester should always update their browser as well as their WebDriver versions; otherwise, there might be some compatibility issues due to different versions of WebDriver and the Web Browser.
3. Selenium Grid
Selenium Grid is a tool that allows parallel execution of test scripts across different browsers on different platforms. It becomes suitable for distributed testing and is very useful for testers. It lets the tester run test scripts simultaneously in different browsers on different platforms, which significantly reduces the execution time and optimizes the automation endeavor.
There are mainly two parts to a Selenium Grid:
- Hub: It acts as the center point and keeps track of the test scripts that are being distributed between different nodes, what results they are returning, etc. In simpler terms, it keeps track of all the scripts running parallel on different devices what results they are returning, and what problems they are facing.
- Node: Nodes are either different machines or browsers in which the test cases run.
Benefits of Selenium Grid:
- Parallel Execution of Test Cases: Selenium Grid allows testers to simultaneously execute test cases in different browsers or different platforms, which heavily reduces the execution time and makes the entire process more efficient.
- Easily Scalable: As Grid works on the concept of hubs and Nodes, it is easy to scale the entire system by adding as many nodes as we want. Which makes it suitable for large-scale automation testing.
- Cross-Browser and Cross-Platform Testing: Grid supports cross-browser and cross-platform simultaneous testing of testing scripts.
- Cost Management: Grid is cost-efficient because it simultaneously executes the same test case on different machines at the same time. So those hardware components can be later used to run different test cases simultaneously. In this way, the cost of buying and using new hardware is decreased.
Limitations of Selenium Grid:
- Complex to Setup: As Selenium Grid solely works on the concept of hubs and nodes, it is not easy to set up the entire system.
- Extra cost for Maintenance: As the number of nodes increases, the overall cost of the system also increases. The cost of maintaining them rises as well.
- Dependent on Network: Grid solely depends on communication between the nodes and the Hub. So if there is any issue with the network, then the entire system might collapse.
- Limited Support for Mobile Devices: Grid can’t work with Mobile Devices.
4. Selenium Remote Control (Deprecated)
Selenium Remote Control was the predecessor of the Selenium Web Driver. Before the creation of WebDriver, it was used by testers to interact with web elements via a JavaScript Program. But after the arrival of WebDriver, it has been deprecated as WebDriver is much more efficient than Remote Control, as it supports multiple programming languages.