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DHANUSH

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Python selenium architecture

Selenium is a powerful tool for automating web browesrs and its architecture is designed to allow scripts to interact with web page just as a human would. Here a detailed breakdown of the selenium architecture.

  1. Selenium components:
  • selenium web drive: this is core component of selenium.it provodes a programming interface to interact with web browsers. Web driver interacts with the browser directly without any middle layer.

  • selenium server: used for remote execution of web driver scripts.it acts as a middleware between the test code and the browser

  • selenium grid: used to distribute the execution of the cases across different environments machines.

  1. Selenium Web Drive architecture:

selenium web driver follows a client server architecture. Here's how it structured:

  • Clint (Test script/code):

    • The clint can any of the supportes programming languages (python, java, c#,etc).
    • The script contains commands that are translstes into HTTP requests.
      • JSON Wire protocol:
    • WebDriver uses the JSON Wirw protocal to communication between the client libraries and server.
    • these requests contain actions like find elemenr, click, get, etc.
      • Browser specific driver
      • Each browser has a specific driver like chromedriver for chrome geckodriver for firefox, etc.
      • the webdrive sends the HTTP requests to the browser driver.
  1. Selenium grid architecture

1.Hub

  • The cental point of the selenium grid.

  • receives test requests form the client.

2.Nodes

  • Nodes are actual machines where the tests are executed.

  • the hub forwards the test commands to the nodw which then executes the test on its local browser instance.

  1. Execution flow in selenium:
  • test script initialization:

    • Thu user writes test scripts in a language like python useing selenium libraries
      • Command Execution:
    • the script generates WebDriver commands.

    command are send as HTTP requests to the browse driver via JSON Wier protacol.

    • Browser interaction:
      • THe browser drive receives the commands and translates them to the native browser language
      • The browser executes these commands.
    • Resulting Reporting:
      • the browser driver collectes the results and sends them back as HTTP responses.
  1. Advance features:
  • Page object model (POM): A desing pattern to creat object repositories for web UI elements.

  • Action Chains: Used for complex user interaction like drag and drop and right-click,etc.

  1. Python selenium bindings:
  • Selenium, web driver: This model provide the methods and classes required to interact with browser.

*Find-element-by id(),,click(),send-key():

* Mothed to interact with web elements.
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QUESTION NUM 2

The significance of the python virtual in environment:

  • The Python virtual environment is a critical tool for managing dependencies and configurations in Python projects. Here's why it's significant, along with some practical examples.

Significance of Python Virtual Environments:

Isolation of Dependencies:

What It Does:

  • A virtual environment allows you to create an isolated space for a Python project where you can install specific versions of libraries and packages without affecting the global Python installation.

Example:

  • Suppose you’re working on two projects, Project A and Project B. Project A requires requests version 2.20, while Project B needs version 2.26. By using virtual environments, you can create separate environments for each project, ensuring that each uses the correct version of requests without conflicts. Avoiding Conflicts:

What It Does:

  • Virtual environments prevent dependency conflicts by keeping project-specific packages separate from the system-wide Python packages.

Example:

  • If Project C relies on Django 2.2 but another project, Project D, requires Django 3.0, a virtual environment for each project ensures that they don’t interfere with each other’s Django versions.

Reproducibility:

What It Does:

  • Using virtual environments helps ensure that your project’s dependencies are consistent across different development setups. You can specify exact versions of packages in a requirements.txt file.

Example:

  • If you need to collaborate with a team or deploy your project to production, you can use pip freeze > requirements.txt to capture the exact versions of the libraries in your virtual environment. This file can then be used to recreate the environment elsewhere using pip install -r requirements.txt.

Ease of Management:

  • What It Does: Virtual environments simplify managing dependencies for multiple projects. You can activate and deactivate environments as needed, keeping your workspace organized.

Example:

  • You might be working on a data science project that requires specific versions of data processing libraries. By creating a virtual environment, you can quickly switch between this project and another one that uses different libraries without manual adjustments.

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