Selenium Grid Tutorial: Hub & Node (with Example) (medium)

Selenium Grid

• Selenium Grid 1 is being deprecated by the Selenium Team.

Selenium Grid Architecture

• There can be multiple nodes in a Selenium Grid.
• Tests are loaded into the hub in Selenium Grid.
• The hub is launched on a machine, which can be different from the nodes.

Node and Hub

• The node component executes the tests loaded on the hub.
• Machines running the nodes do not need to be the same platform as the hub.

Purpose of Selenium Grid

• The purpose of Selenium Grid is to run tests in parallel on multiple machines, allowing for faster test execution.

DesiredCapabilities

• The DesiredCapabilities object is used to set the type of browser and OS that will be automated.
• The DesiredCapabilities object is imported from the org.openqa.selenium.remote package.

JSON Config File

• The JSON config file is used to configure the hub.
• The command to launch the hub using the JSON config file is java -jar selenium-server-standalone.jar -role hub -hubConfig hub.json.

Grid Console

• The Grid Console is used to monitor the grid and view the nodes and their status.

Launching Hub and Node

• The command to launch the hub on Machine A is java -jar selenium-server-standalone.jar -role hub.
• The hub uses port 4444 by default for its web interface.
• The purpose of launching a node is to register it with the hub and make it available for test execution.

Selenium Grid 1 and 2

• Selenium Grid 2 is an improvement over Selenium Grid 1, with a more scalable and flexible architecture.

Benefits of Selenium Grid

• The benefits of using Selenium Grid include faster test execution, parallel testing, and the ability to test on multiple browsers and platforms.

Grid Concepts

• Selenium Grid uses the concept of parallel testing to run multiple tests simultaneously on different browsers and platforms.

Verifying Hub

• The hub can be verified by checking the Grid Console or by using the command curl <a href="http://localhost:4444/grid/console">http://localhost:4444/grid/console</a>.

RemoteWebDriver

• The RemoteWebDriver object is used to execute tests on a remote node.

Installing Selenium Grid

• Selenium Grid can be installed by downloading the Selenium Server JAR file and running it with the java command.