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Vignesh
Vignesh

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Task18

Describe the Python Selenium architecture in detail?

What is the significance of the Python Virtual Environment? Give Some Example to support your answer?

Python Selenium Architecture:

Selenium WebDriver stands as a widely utilized open-source library and integral element within the Selenium automation framework. Its primary function involves automating the testing procedures for web applications. This technology comprises a set of APIs that provide a programming interface, empowering developers, and testers to craft scripts in diverse programming languages like Java, JavaScript, C#, Python, etc. These scripts are designed to automate actions within web browsers and extract information from web pages. WebDriver operates by replicating user actions, navigating across web pages, engaging with various elements (ranging from buttons, text fields, dropdown menus, forms, links, etc.), submitting forms, executing validations, performing assertions, and executing numerous other functions through test scripts.

The architecture of Selenium WebDriver (Selenium 3) comprises four primary components:

Selenium Client library: The Selenium Client Library encompasses languages such as Java, Ruby, Python, C#, and more. Once the test cases are initiated, the complete Selenium code will be transformed into JSON format.

JSON wire protocol over HTTP: JSON stands for JavaScript Object Notation, handling the transmission of information from the server to the client. The JSON Wire Protocol predominantly manages the transfer of data between HTTP servers. The produced JSON is accessible to browser drivers via the HTTP protocol.

Browser Drivers: Selenium’s browser drivers are inherently specific to each browser, establishing secure connections and enabling interaction with the browser. Selenium extends support for various browser drivers such as ChromeDriver, GeckoDriver, Microsoft Edge WebDriver, SafariDriver, and InternetExplorerDriver.

Browsers: One of the greatest advantages of Selenium WebDriver is its compatibility with all major browsers including Firefox, Google Chrome, Apple Safari, IE, Edge, and Opera. Each browser has its dedicated WebDriver for running automation scripts.

Selenium WebDriver Architecture

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Python Virtual Environment:

A Python virtual environment refers to an independent Python environment enabling the management of distinct dependencies for individual Python projects. Creating a Python virtual environment for each project guarantees that it will possess its necessary requirements without any interference from other projects.

What is the reason behind using a Python Virtual Environment?

While working with Python, we might find the need to install packages and modules that aren’t included in the standard library. Employing ‘pip install –user some_package’ enables the installation of Python packages in your home directory. However, potential issues may arise later regarding package dependencies.

Eg:

If developers are simultaneously handling two different projects — Project A requiring version 1.0 of a library and Project B necessitating version 2.0 of the same library — installing the dependency for Project B could potentially disrupt Project A. To circumvent this issue, creating separate virtual environments for each project is a simple solution. These virtual environments remain isolated from one another, allowing you to install dependencies for one project without concerns about affecting the other.

Functioning principle of a virtual environment

Installing virtualenv:

$ pip install virtualenv

Test the installation:

$ virtualenv — version

Creating a virtualenv using the following command:

$ virtualenv dir_name

*dir_name- Directory name

To create a Python 3 virtual environment, use the following command:

$ virtualenv -p /usr/bin/python3.X virtualenv_name

Deactivate a Python virtualenv:

(virtualenv_name)$ deactivate

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