final commit

db.js

@@ -5,21 +5,97 @@ const { DB_URI } = process.env;
 let dbConnection;
 
 module.exports = {
-  connectToDb: (cb) => {
-    MongoClient.connect(DB_URI)
-      .then((client) => {
-        dbConnection = client.db();
-        return cb();
-      })
-      .catch((err) => {
-        console.log(err);
-        return cb(err);
+  connectToDb: async () => {
+    try {
+      const client = new MongoClient(DB_URI, {
+        useNewUrlParser: true,
+        useUnifiedTopology: true,
       });
+      await client.connect();
+      console.log("MongoDB connected successfully");
+      dbConnection = client.db("e-commerce");
+      return dbConnection;
+    } catch (err) {
+      console.error("MongoDB connection error:", err);
+      throw err;
+    }
   },
-  getDb: () => dbConnection,
-  getOrderModel: () => dbConnection.collection("orders"),
-  getUserModel: () => dbConnection.collection("users"),
-  getCustomerEnquiries: () => dbConnection.collection("customer-enquiries"),
-  getNewsletter: () => dbConnection.collection("newsletters"),
-  getResetPwd: () => dbConnection.collection("reset-password"),
+  startServer: async (app, port) => {
+    try {
+      if (!dbConnection) {
+        throw new Error('Database connection has not been established.');
+      }
+
+      await app.listen(port);
+      console.log(`App listening on port ${port}`);
+    } catch (err) {
+      console.error('Error starting server:', err);
+      throw err;
+    }
+  },
+
+  getOrderModel: () => {
+    if (!dbConnection) {
+      throw new Error('Database connection has not been established.');
+    }
+    return dbConnection.collection("orders");
+  },
+
+  getCategoryModel:()=>{
+    if (!dbConnection) {
+      throw new Error('Database connection has not been established.');
+    }
+    return dbConnection.collection("categories");
+  },
+
+  getProductsModel:()=>{
+    if (!dbConnection) {
+      throw new Error('Database connection has not been established.');
+    }
+    return dbConnection.collection("products");
+  },
+
+  getFaqsModel:()=>{
+    if (!dbConnection) {
+      throw new Error('Database connection has not been established.');
+    }
+    return dbConnection.collection("faqs");
+  },
+
+
+  getUserModel: () => {
+    if (!dbConnection) {
+      throw new Error('Database connection has not been established.');
+    }
+    return dbConnection.collection("users");
+  },
+
+  getCartModel: () => {
+    if (!dbConnection) {
+      throw new Error('Database connection has not been established.');
+    }
+    return dbConnection.collection("cart");
+  },
+
+
+  getCustomerEnquiries: () => {
+    if (!dbConnection) {
+      throw new Error('Database connection has not been established.');
+    }
+    return dbConnection.collection("customer-enquiries");
+  },
+
+  getNewsletter: () => {
+    if (!dbConnection) {
+      throw new Error('Database connection has not been established.');
+    }
+    return dbConnection.collection("newsletters");
+  },
+
+  getResetPwd: () => {
+    if (!dbConnection) {
+      throw new Error('Database connection has not been established.');
+    }
+    return dbConnection.collection("reset-password");
+  }
 };