ai-code-review

### Code Review Report: Security Audit
**Provider:** OpenAI (GPT-4)
**Language:** Python
**Review Type:** Security
**Target Area:** SQL Injection Vulnerabilities

**Complexity Score:** 7/10
**Files Reviewed:** `user_auth.py` (Lines 42-89)

---

#### Critical Issues Found
1. **SQL Injection Risk (Line 57-61)**
   ```python
   query = f"SELECT * FROM users WHERE username = '{username}' AND password = '{password}'"
   ```
   **Risk:** High. User input is directly interpolated into SQL. Attackers can bypass authentication with `' OR '1'='1`.
   **Fix:** Use parameterized queries:
   ```python
   query = "SELECT * FROM users WHERE username = %s AND password = %s"
   cursor.execute(query, (username, password))
   ```

2. **Hardcoded Secret (Line 78)**
   ```python
   API_KEY = "sk-1234567890abcdef"
   ```
   **Risk:** High. Secrets in code violate OWASP guidelines. 
   **Fix:** Use environment variables:
   ```python
   import os
   API_KEY = os.getenv("STRIPE_API_KEY")
   ```

---

#### Performance Optimizations
- **Line 45:** The `get_user_by_id()` function uses a linear search. Replace with a dictionary lookup (O(1) vs O(n)):
  ```python
  user_cache = {}
  def get_user_by_id(user_id):
      return user_cache.get(user_id)
  ```

---

#### Developer Skill Assessment
- **Security Awareness:** 6/10 (missed critical SQLi and hardcoded secrets)
- **Performance:** 7/10 (could optimize data structures)
- **Recommendation:** Complete the [OWASP Top 10](https://owasp.org/www-project-top-ten/) training module.

**Next Steps:**
1. Apply the SQL injection fix immediately.
2. Rotate the hardcoded API key.
3. Schedule a team workshop on secure coding practices.