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Ashnet A
Ashnet A

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Python Selenium Architecture

*Python Selenium Architecture: *

                  Selenium is a browser automation framework that allows controlling browsers through WebDriver APIs. It supports various languages, including Python, and works with all major browsers (Chrome, Firefox, Edge, Safari, etc.).

                 The term "Python vertical environment" is not a standard phrase in the Python ecosystem, but based on context, you may be referring to one of the following:

                 I'll assume you meant Python Virtual Environment, which is a crucial concept in Python development. Let’s explore that in detail.
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• Understand how to manage dependencies in Python projects.
• Learn how to avoid version conflicts.
• Work on multiple Python projects without them interfering.
• Improve your understanding of deployment, testing, and collaboration

  1. Python Client Bindings • Python developers write test or automation scripts using the Selenium Python bindings (selenium package). • These bindings are a Python wrapper around the WebDriver API, and translate Python commands into HTTP requests understood by the browser-specific WebDriver. 2.** WebDriver API ** • This is the communication layer between your Python code and the browser. • It uses HTTP requests and JSON payloads to send commands and receive responses. • There are two protocols: o JSON Wire Protocol (used in earlier versions) o W3C WebDriver Protocol (current standard since Selenium 4)
  2. Browser-Specific WebDriver Executables • A WebDriver executable is a bridge between Selenium and the actual browser. • Examples: o chromedriver for Chrome o geckodriver for Firefox o msedgedriver for Edge • These executables receive commands from Selenium over HTTP and forward them to the actual browser. The driver performs actions like: • Opening a page • Clicking a button • Extracting text • Taking screenshots • Executing JavaScript
  3. Browser (Chrome, Firefox, Edge, Safari) • The real browser is launched and controlled via its driver. • WebDriver interacts with the browser’s native APIs to control UI components and retrieve DOM content. • User writes a Python script using Selenium's API. • Selenium converts the commands into HTTP requests (W3C WebDriver commands). • These requests are sent to the WebDriver executable, which acts like an HTTP server. • The WebDriver interacts with the browser using its internal APIs. • The browser executes the command and returns a response. • The WebDriver sends back a response to the Selenium Python bindings. • The script continues with the next command. Component Role Python Bindings User interface to write automation logic in Python WebDriver API Standard protocol to send commands over HTTP WebDriver Executable Middleware between Selenium and browser Browser Executes the actual commands on web pages Selenium Grid Parallel & distributed test execution

Python Virtual Environment:
A Python virtual environment is an isolated workspace that allows you to install and manage Python packages separately for each project, without interfering with other projects or the system-wide Python installation.
Each project can maintain its own dependencies without conflicts.
* You avoid polluting your system Python installation with unnecessary or conflicting packages.
* You can freeze and export the list of dependencies using requirements.txt and recreate the exact environment elsewhere.
* You can freeze and export the list of dependencies using requirements.txt and recreate the exact environment elsewhere.
* Automated build systems, Docker containers, and cloud deployment pipelines rely on isolated environments for consistency.
**Without Virtual Environment:*
• Version conflicts between packages
• Harder to reproduce bugs
• System-level Python becomes cluttered
• Collaboration becomes error-prone
EXAMPLE OF VIRTUAL ENVIRONMENT

Step 1: Create a virtual environment 

      python -m venv myenv
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Step 2: Activate the environment 

      On Windows:
      myenv\Scripts\activate
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Step 3: Install packages 

      pip install flask
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Step 4: Save dependencies 

      pip freeze > requirements.txt
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Step 5: Deactivate when done 

      deactivate
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