Legacy Codebase Modernization

Automatically refactor deprecated scripts into modern, secure, and idiomatic architectures.

Legacy Input (e.g., Python 2.7 / CGI) legacy_handler.py

import cgi
import sqlite3

def application(environ, start_response):
    form = cgi.FieldStorage(fp=environ['wsgi.input'], environ=environ)
    user_id = form.getvalue("id")
    
    conn = sqlite3.connect('app.db')
    cursor = conn.cursor()
    # SQL Injection vulnerability present in legacy code
    cursor.execute("SELECT * FROM users WHERE id = " + str(user_id))
    user = cursor.fetchone()
    
    status = '200 OK'
    headers = [('Content-type', 'text/html')]
    start_response(status, headers)
    
    if user:
        return ["<html><body>Hello, %s</body></html>" % user[1]]
    else:
        return ["<html><body>Not found</body></html>"]

Modern Output (FastAPI / ORM)

Awaiting Input

from fastapi import FastAPI, HTTPException, Depends
from sqlalchemy.orm import Session
from .database import get_db, User

app = FastAPI()

@app.get("/users/{user_id}")
def get_user(user_id: int, db: Session = Depends(get_db)):
    # Vulnerability patched: SQLAlchemy handles parameter binding
    user = db.query(User).filter(User.id == user_id).first()
    
    if not user:
        raise HTTPException(status_code=404, detail="User not found")
        
    return {"message": f"Hello, {user.name}"}