Initial commit: Character sandbox with React+Express frontend/backend, SvelteKit foundation

server/middleware/auth.js

@@ -0,0 +1,26 @@
+import jwt from 'jsonwebtoken';
+
+const JWT_SECRET = process.env.JWT_SECRET || 'sandbox-secret-key-change-in-production';
+
+export function generateToken(userId) {
+  return jwt.sign({ userId }, JWT_SECRET, { expiresIn: '7d' });
+}
+
+export function authenticateToken(req, res, next) {
+  const authHeader = req.headers['authorization'];
+  const token = authHeader && authHeader.split(' ')[1];
+
+  if (!token) {
+    return res.status(401).json({ error: 'Authentication required' });
+  }
+
+  jwt.verify(token, JWT_SECRET, (err, decoded) => {
+    if (err) {
+      return res.status(403).json({ error: 'Invalid or expired token' });
+    }
+    req.userId = decoded.userId;
+    next();
+  });
+}
+
+export { JWT_SECRET };