CommandRunner API: A Unified Solution for OS and Math Operations

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Project Overview

This project demonstrates a client-server application using Django REST Framework (DRF) and ZeroMQ (ZMQ) for communication. The server processes two types of commands:

1. OS Commands: Executes system commands like ping, ls, or echo.
2. Math Commands: Evaluates basic arithmetic expressions such as (2 + 3) * 4.

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Technologies Used

1. Django: Python web framework for building the server-side application.
2. Django REST Framework (DRF): Simplifies API development.
3. ZeroMQ (ZMQ): A high-performance messaging library for client-server communication.

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Features

• Processes OS and Math commands.
• Communicates between client and server using ZeroMQ.
• API endpoint for executing commands.
• Handles invalid commands gracefully with error responses.

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How to Set Up and Run

1. Prerequisites

• Python 3.8 or higher installed.
• Install required libraries:

  pip install django djangorestframework pyzmq

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2. Start the ZeroMQ Server

Navigate to the project directory and run the server:

python core/zmq_server.py

The server will start listening on tcp://*:5555.

Press Ctrl + C to Stop:

Output:

[INFO] Server is running...
[INFO] Received message: {'command_type': 'os', 'parameters': ['echo', 'Hello']}
[INFO] Sending response: {'status': 'success', 'result': 'Hello\n'}
^C
[INFO] Server is shutting down...
[INFO] Server closed.

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3. Run the Django Application

Start the Django development server:

python manage.py runserver

The API will be available at http://127.0.0.1:8000/api/execute-command/.

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4. Test the API

You can send POST requests to the /api/execute-command/ endpoint using Postman, curl, or similar tools.

Example: OS Command

Request:

POST http://127.0.0.1:8000/api/execute-command/
{
  "command_type": "os",
  "parameters": ["echo", "Hello, World!"]
}

Response:

{
  "status": "success",
  "result": "Hello, World!\n"
}

Example: Math Command

Request:

POST http://127.0.0.1:8000/api/execute-command/
{
  "command_type": "compute",
  "expression": "(5 + 3) * 2"
}

Response:

{
  "status": "success",
  "result": 16
}

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5. Run Tests

Run the Django unit tests:

python manage.py test

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How It Works

1. Client Sends Command: A JSON request is sent to the /api/execute-command/ endpoint.
2. API Processes Request: The Django view sends the command to the ZeroMQ server.
3. Server Executes Command: The ZeroMQ server processes the command (OS or Math) and returns the result.
4. Response Sent Back: The API sends the response back to the client.

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Optional Features

• unit tests: Implemented unit tests for the client and server in tests.py.
• Logging: Added command logging in zmq_server.py.