Selenium Grid

Selenium Grid is a powerful tool that facilitates parallel test execution across multiple browsers, operating systems, and machines. It allows you to distribute test execution on different environments, providing faster test execution and improved efficiency in running tests concurrently.

Key Components of Selenium Grid:

  1. Hub: Acts as a central point to manage and distribute test requests to various nodes.
  2. Node: Represents the actual test execution environment where tests are run on different browsers and platforms.

Setting up Selenium Grid

Step 1 : Download Selenium Server (Grid):

In order to run Remote Selenium WebDriver you need tp download Selenium Server. Click here to download from official website.

Step 2 : Start the Hub:

java -jar selenium-server-standalone-.jar -role hub

Step 3 : Start Nodes

java -Dwebdriver.chrome.driver="chromedriver_path" -jar selenium-server-standalone-.jar -role node -hub http://localhost:4444/grid/register -port

Replace "chromedriver_path" with the path to your ChromeDriver and with an available port.

Benefits of Selenium Grid

  • Parallel Execution: Run tests concurrently across multiple environments, reducing overall execution time.
  • Cross-browser Testing: Test web applications on different browsers and versions simultaneously.
  • Scalability: Easily scale up by adding or removing nodes based on testing requirements.
  • Cost-effective: Optimize resources by distributing tests on various machines.

Java
C#
Python
Javascript
Kotlin
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ChromeOptions options = new ChromeOptions();
//Add capability
//options.setCapability("");
WebDriver driver = new RemoteWebDriver(new URL("http://localhost:4444"), options);
driver.get("https://www.testautomationstudio.com/demo/home/");

driver.quit();
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ChromeOptions options = new ChromeOptions();
//Add Options
options.AddArgument("--headless");
IWebDriver driver = new RemoteWebDriver(new Uri("http://localhost:4444"), options);
driver.Url = "https://www.testautomationstudio.com/demo/home/";
driver.Manage().Timeouts().ImplicitWait = TimeSpan.FromSeconds(30);
driver.Manage().Window.Maximize();
driver.Quit();
Python code coming soon
Javascript code coming soon
Kotlin code coming soon
Selenium v4.0

Selenium Grid 4 is a brand-new version created entirely from scratch, different from its earlier versions. It comes with many enhancements that make it faster and more aligned with current standards. This new version reorganizes the grid's various functions to match the way technology and software are developed today.


The design of Selenium Grid 4 specifically focuses on being compatible with containerization (like Docker) and being easily scalable in cloud environments. It's essentially a completely new solution that's well-suited for the way technology works in today's world.

Following are different ways you can make use of Grid depending upon your needs.

Standalone

Selenium Standalone mode brings together all the parts of Selenium Grid into one. It's like having a complete Grid setup by just using one command and within a single program on your computer. However, Standalone mode can only run on one machine.


Using Standalone mode is the simplest way to start a Selenium Grid. When you start the server in Standalone mode, it automatically waits for requests from RemoteWebDriver at http://localhost:4444. It also checks your computer's settings to find the drivers it needs by default.


To start the Grid in standalone mode run the following command.

java -jar selenium-server.jar standalone

Hub and Node

The Hub and Node roles in Selenium Grid are really popular because they let you do a few important things:

  • Combine Different Machines: You can connect various computers into one Grid. These computers might have different operating systems or different versions of web browsers.
  • Run Tests in Different Environments: You can start tests using WebDriver from just one place, even if you want to test on many different setups.
  • Change the Size of Your Grid Easily: You can increase or decrease the number of machines in your Grid without needing to shut it all down.

A Hub is composed by Router, Distributor, Session Map, New Session Queue, and Event Bus. To start the Grid in Hub mode run the following command.

java -jar selenium-server.jar hub

Node can be configured on same machine as Hub or it can be configured on multiple machines with different OS. To configure Node on same machine run the following command.

java -jar selenium-server.jar node

To configure Node on different machine run the following command.

java -jar selenium-server.jar node --hub http://:4444