🛡️ Secure Python Code Execution Server

This project provides a secure web-based Python execution server with sandboxing, memory limits, execution timeouts, and persistent sessions.

👉 Cross-platform: Works on both Linux & Windows
👉 Session Management: Maintain variables across executions
👉 Security Features: Blocks dangerous imports (os, sys, subprocess, etc.)
👉 Execution Limits:

• Max Memory: 100MB per session
• Max Execution Time: 2 seconds
  👉 Web UI: User-friendly interface for running code

---

🚀 Getting Started

1️⃣ Installation

🔹 Prerequisites

Ensure you have Python 3.8+ installed.

📌 clone the repo:

git clone https://github.com/ah0048/Python-Code-Execution-Server.git
cd Python-Code-Execution-Server

📌 create a virtual environment:

• On Linux/macOS:

python3 -m venv venv

• On Windows:

python -m venv venv

📌 activate the virtual environment:

• On Linux/macOS:

source venv/bin/activate

• On Windows:

venv\Scripts\activate

📌 Install dependencies:

pip install -r requirements.txt

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2️⃣ Running the Server

🔹 On Linux / Mac

python3 run.py

🔹 On Windows (Command Prompt / PowerShell)

python run.py

The server will start at:
📌 http://127.0.0.1:5000/

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3️⃣ Using the Web UI

1️⃣ Open your browser and go to http://127.0.0.1:5000/
2️⃣ Write Python code in the editor
3️⃣ Click "Execute" to run it
4️⃣ (Optional) Enter a Session ID to persist variables across executions

---

API Usage

🔹 Execute Python Code

📌 Endpoint:

POST /execute

📌 Request Body (JSON):

{
    "code": "print('Hello, World!')",
    "id": "optional-session-id"
}

📌 Response Example:

{
    "id": "123e4567-e89b-12d3-a456-426614174000",
    "stdout": "Hello, World!\n"
}

🔹 Error Handling

If an error occurs, the response will include an "error" field instead of "stdout" or "stderr".

Example (Timeout Exceeded):

{
    "id": "123e4567-e89b-12d3-a456-426614174000",
    "error": "Execution timeout. Session terminated."
}

---

🔒 Security & Execution Restrictions

This server restricts unsafe operations to prevent security risks.

1️⃣ Blocked Modules

The following dangerous modules are blocked:
🚫 os, sys, socket, subprocess, shutil, pathlib, open

Example (Blocked Code):

import os
os.system("rm -rf /")  # ❌ Not Allowed!

📌 Response:

{
    "stderr": "Traceback (most recent call last):\nPermissionError: Importing 'os' is restricted.\n"
}

---

2️⃣ Execution Limits

Limit	Value
Max Execution Time	2 seconds
Max Memory Usage	100MB

Example (Infinite Loop):

while True: pass

📌 Response:

{
    "error": "Execution timeout. Session terminated."
}

Example (Exceeding Memory Limit):

a = " " * 1024 * 1024 * 200  # Allocate 200MB

📌 Response:

{
    "error": "Memory limit exceeded. Session terminated."
}

---

🛠️ Known Limitations

🔹 File System & Network Access Blocked
🔹 No Support for Asynchronous Execution (async functions may not work properly)
🔹 Cannot Execute Multi-Threaded Code (threading is blocked)

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🎯 Summary

• Python Flask Server for executing code securely
• Memory & Execution Time Limits enforced
• Persistent Sessions to store variables across executions
• Web UI for easy testing
• Works on both Windows & Linux

💡 Future Improvements:

• Add Docker support for stricter sandboxing
• Implement rate limiting to prevent abuse
• Support async execution and classes build