Selenium Components | Selenium Tutorial pdf

Selenium Components

Selenium is composed of three major tools. Each one has a specific role in aiding the development of web application test automation.

Selenium-IDE

Selenium-IDE is the Integrated Development Environment for building Selenium test cases. It operates as a Firefox add-on and provides an easy-to-use interface for developing and running individual test cases or entire test suites. Selenium-IDE has a recording feature, which will keep account of user actions as they are performed and store them as a reusable script to play back. It also has a context menu (right-click) integrated with the Firefox browser, which allows the user to pick from a list of assertions and verifications for the selected location. Selenium-IDE also offers full editing of test cases for more precision and control.
Although Selenium-IDE is a Firefox only add-on, tests created in it can also be run against other browsers by using Selenium-RC and specifying the name of the test suite on the command line.

Selenium-RC (Remote Control)

Selenium-RC allows the test automation developer to use a programming language for maximum flexibility and extensibility in developing test logic. For instance, if the application under test returns a result set, and if the automated test program needs to run tests on each element in the result set, the programming language’s iteration support can be used to iterate through the result set, calling Selenium commands to run tests on each item.
Selenium-RC provides an API (Application Programming Interface) and library for each of its supported languages: HTML, Java, C#, Perl, PHP, Python, and Ruby. This ability to use Selenium-RC with a high level programming language to develop test cases also allows the automated testing to be integrated with a  project’s automated build environment.

Selenium-Grid

Selenium-Grid allows the Selenium-RC solution to scale for large test suites or test suites that must be run in multiple environments. With Selenium-Grid multiple instances of Selenium-RC are running on various operating system and browser configurations, each of these when launching register with a hub. When tests are sent to the hub they are then redirected to an available Selenium-RC, which will launch the browser and run the test. This allows for running tests in parallel, with the entire test suite theoretically taking only as long to run as the longest individual test.