New 2 done

backend/.env

@@ -0,0 +1 @@
+MONGO_URI=mongodb+srv://root:root@book-store-mern.qar8fzj.mongodb.net/?appName=Book-Store-MERN

backend/api/index.js

@@ -0,0 +1,50 @@
+import express from 'express';
+import mongoose from 'mongoose';
+import cors from 'cors';
+import booksRoute from '../routes/booksRoute.js';
+
+// On Vercel, set MONGO_URI in Project Settings -> Environment Variables.
+// Locally (via `vercel dev`), it will read from backend/.env if you use
+// something like `vercel env pull` or `dotenv` — see README notes below.
+const mongoDBURL = process.env.MONGO_URI;
+
+const app = express();
+
+app.use(express.json());
+app.use(cors());
+
+app.get('/', (request, response) => {
+  return response.status(200).send('Welcome To MERN Stack Tutorial (Vercel)');
+});
+
+app.use('/books', booksRoute);
+
+// Serverless functions can be invoked concurrently and are reused between
+// invocations while "warm", so we cache the DB connection instead of
+// reconnecting on every request.
+let isConnected = false;
+
+async function connectDB() {
+  if (isConnected && mongoose.connection.readyState === 1) return;
+
+  if (!mongoDBURL) {
+    throw new Error(
+      'MONGO_URI environment variable is not set. Add it in Vercel Project Settings.'
+    );
+  }
+
+  await mongoose.connect(mongoDBURL);
+  isConnected = true;
+  console.log('App connected to database');
+}
+
+// Vercel's Node runtime calls this exported function as the request handler.
+export default async function handler(request, response) {
+  try {
+    await connectDB();
+    return app(request, response);
+  } catch (error) {
+    console.error(error);
+    return response.status(500).json({ message: 'Database connection failed' });
+  }
+}

backend/config.js

@@ -1,7 +1,7 @@
 export const PORT = 5555;
 
 export const mongoDBURL =
-  'mongodb+srv://root:root@books-store-mern.c7ba8z1.mongodb.net/books-collection?retryWrites=true&w=majority';
+  'mongodb+srv://root:root@book-store-mern.qar8fzj.mongodb.net/?retryWrites=true&w=majority&appName=Book-Store-MERN';
 
 // Please create a free database for yourself.
 // This database will be deleted after tutorial

backend/index.js

@@ -1,3 +1,6 @@
+import dns from 'dns';
+dns.setServers(['1.1.1.1', '8.8.8.8']);
+
 import express from 'express';
 import { PORT, mongoDBURL } from './config.js';
 import mongoose from 'mongoose';
@@ -27,7 +30,7 @@ app.get('/', (request, response) => {
 });
 
 app.use('/books', booksRoute);
-
+console.log(mongoDBURL);
 mongoose
   .connect(mongoDBURL)
   .then(() => {
@@ -37,5 +40,6 @@ mongoose
     });
   })
   .catch((error) => {
-    console.log(error);
+    console.error(error);
+    console.error(error.message);
   });

backend/models/bookModel.js

@@ -10,7 +10,7 @@ const bookSchema = mongoose.Schema(
       type: String,
       required: true,
     },
-    publishYear: {
+    publishedYear: {
       type: Number,
       required: true,
     },