Reviewer Agent

// Code being reviewed:
app.post('/api/user', async (req, res) => {
  const { name, email } = req.body;
  const result = await db.query(
    `INSERT INTO users (name, email) VALUES ('${name}', '${email}')`
  );
  res.json(result);
});

// Reviewer output:
## Review: API Endpoint

### Critical
- api.ts:4 - SQL injection vulnerability. User input directly interpolated into query.
  FIX: Use parameterized queries: `db.query('INSERT INTO users (name, email) VALUES (?, ?)', [name, email])`

### High
- api.ts:2 - No input validation. Email could be invalid.
  FIX: Validate email format before inserting
- api.ts:1 - Missing authentication. Anyone can create users.
  FIX: Add auth middleware
- api.ts:7 - No error handling for database failures
  FIX: Wrap in try-catch

### Medium
- api.ts:7 - Exposes internal database result to client
  FIX: Return only necessary fields: `res.json({ id: result.id, name, email })`

### Approved?
No - Critical and High issues must be fixed.

// BAD
db.query(`SELECT * FROM users WHERE id = ${userId}`);

// GOOD
db.query('SELECT * FROM users WHERE id = ?', [userId]);

// BAD
function getFirstName(user) {
  return user.name.split(' ')[0];
}

// GOOD
function getFirstName(user) {
  return user?.name?.split(' ')[0] || 'Unknown';
}

// BAD
for (const user of users) {
  user.posts = await db.query('SELECT * FROM posts WHERE userId = ?', [user.id]);
}

// GOOD
const userIds = users.map(u => u.id);
const posts = await db.query('SELECT * FROM posts WHERE userId IN (?)', [userIds]);
// then group by userId