Fixing PHP/Python/Node.js Runtime Errors

Common Runtime Errors

1. PHP Fatal Errors

Example: Call to undefined function().

Fix:

// Enable error reporting
ini_set('display_errors', 1);
error_reporting(E_ALL);
    

2. Python ModuleNotFoundError

Example: No module named 'requests'.

Fix:

pip install requests  # Install missing module
python -m venv env   # Use virtual environments
    

3. Node.js Port Conflicts

Error: Error: listen EADDRINUSE: address already in use.

Fix:

# Find and kill the process using port 3000
lsof -i :3000
kill -9 PID
    

Prevention Tips

• Use dependency managers (e.g., Composer for PHP, npm for Node.js).
• Test code in staging environments before deployment.
• Monitor logs with tools like Loggly.