port

server.js

@@ -9,11 +9,12 @@ const surveyController = require('./controllers/surveyController');
 const responseController = require('./controllers/responseController'); 
 var app = express();
 app.use(bodyParser.json())
-app.listen(3000, () => {
+const port = process.env.PORT || 3000;
+app.listen(port, () => {
     console.log('Express server started at port: 3000');
 });
 app.use(cors());
 app.use('/user', userController); 
 app.use('/survey', surveyController);
 app.use('/response', responseController); 
- 
+app.get('/', (req, res) => res.send('Home Page Route'));

vercel.json

@@ -3,5 +3,17 @@
     "version": 2,
     "env": {
       "MONGODB_URI": "@my-mongodb-uri"
-    }
+    },
+    "builds": [
+        {
+            "src": "./server.js",
+            "use": "@vercel/node"
+        }
+    ],
+    "routes": [
+        {
+            "src": "/(.*)",
+            "dest": "/"
+        }
+    ]
   }