implemented a simple backend for mobile banking

src/controllers/auth.controller.js

@@ -0,0 +1,25 @@
+const { validateUser } = require('../services/auth.service');
+const { generateToken } = require('../util/jwt');
+const { logger } = require('../util/logger');
+
+async function login(req, res) {
+  const { customerNo, password } = req.body;
+
+  if (!customerNo || !password) {
+    return res
+      .status(400)
+      .json({ error: 'customerNo and password are required' });
+  }
+
+  try {
+    const user = await validateUser(customerNo, password);
+    if (!user) return res.status(401).json({ error: 'invalid credentials' });
+    const token = generateToken(user.customer_no);
+    res.json({ token });
+  } catch (err) {
+    logger.error(err, 'login failed');
+    res.status(500).json({ error: 'something went wrong' });
+  }
+}
+
+module.exports = { login };