feat: implement GraphQL API with Apollo Server

BACKEND/app.js

@@ -20,6 +20,9 @@ import passport from "./config/passport.js";
 import swaggerUi from 'swagger-ui-express';
 import swaggerSpec from './swagger.js';
 import { stripeWebhook } from "./controllers/checkout.controller.js";
+import { expressMiddleware } from "@as-integrations/express4";
+import { apolloServer } from "./graphql/server.js";
+import { optionalProtect } from "./middleware/auth.js";
 
 // Import error handlers
 import { notFoundHandler, errorHandler } from "./middleware/errorMiddleware.js";
@@ -57,6 +60,18 @@ if (process.env.VITE_API_URL) {
 }
 
 const app = express();
+await apolloServer.start();
+
+app.use(
+  "/graphql",
+  express.json(),
+  optionalProtect,
+  expressMiddleware(apolloServer, {
+    context: async ({ req }) => ({
+      user: req.user || null,
+    }),
+  })
+);
 app.use(
   helmet({
     contentSecurityPolicy: {
@@ -132,4 +147,14 @@ if (process.env.NODE_ENV === "production") {
   });
 }
 
-export default app;
+// ============= ERROR HANDLERS (ALWAYS AT THE BOTTOM) =============
+// 404 handler for unmatched routes (API routes that don't exist)
+app.use(notFoundHandler);
+// Global error handler
+app.use(errorHandler);
+
+export default app;
+
+
+
+

BACKEND/graphql/README.md

@@ -0,0 +1,73 @@
+# GraphQL API
+
+## Endpoint
+
+`/graphql`
+
+Apollo Sandbox is available at:
+
+http://localhost:5000/graphql
+
+## Product Query Example
+
+```graphql
+query GetProducts {
+  products {
+    _id
+    name
+    price
+    image
+    description
+    category
+    brand
+    stock
+    averageRating
+    reviewCount
+  }
+}
+```
+
+## Product Mutation Example
+
+```graphql
+mutation CreateProduct {
+  createProduct(
+    name: "Sample Product"
+    price: 99.99
+    image: "https://example.com/image.png"
+    description: "A sample product"
+    category: "General"
+    brand: "DemoBrand"
+    stock: 10
+  ) {
+    _id
+    name
+    price
+  }
+}
+```
+
+## User Query Example
+
+```graphql
+query GetUsers {
+  users {
+    _id
+    name
+    email
+    avatar
+  }
+}
+```
+
+## Order Query Example
+
+```graphql
+query {
+  orders {
+    _id
+    totalAmount
+    paymentStatus
+  }
+}
+```

BACKEND/graphql/resolvers.js

@@ -0,0 +1,101 @@
+import Product from "../models/product.model.js";
+import User from "../models/user.model.js";
+import Order from "../models/order.model.js";
+import {
+  indexProduct,
+  deleteProductFromIndex,
+} from "../services/elasticsearch.service.js";
+import redis from "../config/redis.js";
+
+async function invalidateProductCache() {
+  if (!redis) return;
+  try {
+    const keys = await redis.keys("products:*");
+    if (keys.length) {
+      await redis.del(...keys);
+    }
+  } catch (error) {
+    console.warn("[Redis] Cache invalidation error:", error.message);
+  }
+}
+
+export const resolvers = {
+  Query: {
+    products: async () => Product.find({ isDeleted: false }),
+    product: async (_, { id }) =>
+      Product.findOne({
+        _id: id,
+        isDeleted: false,
+      }),
+
+    users: async () => User.find(),
+    user: async (_, { id }) => User.findById(id),
+
+    orders: async () => Order.find().populate("user"),
+    order: async (_, { id }) => Order.findById(id).populate("user"),
+  },
+  Mutation: {
+    createProduct: async (_, args, context) => {
+      if (!context.user) {
+        throw new Error("Unauthorized");
+      }
+
+      const product = await Product.create(args);
+      await indexProduct(product);
+      await invalidateProductCache();
+      return product;
+    },
+
+    updateProduct: async (_, { id, ...updates }, context) => {
+      if (!context.user) {
+        throw new Error("Unauthorized");
+      }
+
+      const product = await Product.findByIdAndUpdate(id, updates, {
+        new: true,
+      });
+      if (product) {
+        await indexProduct(product);
+        await invalidateProductCache();
+      }
+      return product;
+    },
+
+    deleteProduct: async (_, { id }, context) => {
+      if (!context.user) {
+        throw new Error("Unauthorized");
+      }
+
+      const deleted = await Product.findByIdAndUpdate(
+        id,
+        { isDeleted: true },
+        { new: true }
+      );
+      if (!deleted) {
+        return false;
+      }
+
+      await deleteProductFromIndex(id);
+      await invalidateProductCache();
+      return true;
+    },
+
+    createUser: async (_, args, context) => {
+      if (!context.user) {
+        throw new Error("Unauthorized");
+      }
+
+      return await User.create(args);
+    },
+
+    deleteUser: async (_, { id }, context) => {
+      if (!context.user) {
+        throw new Error("Unauthorized");
+      }
+
+      const deleted = await User.findByIdAndDelete(id);
+      return !!deleted;
+    },
+  },
+};
+

BACKEND/graphql/schema.js

@@ -0,0 +1,71 @@
+export const typeDefs = `#graphql
+  type Product {
+    _id: ID!
+    name: String!
+    price: Float!
+    image: String!
+    description: String
+    category: String
+    brand: String
+    stock: Int
+    averageRating: Float
+    reviewCount: Int
+  }
+
+  type User {
+    _id: ID!
+    name: String!
+    email: String!
+    avatar: String
+  }
+
+  type Order {
+    _id: ID!
+    totalAmount: Float!
+    paymentStatus: String!
+    stripeSessionId: String!
+  }
+
+  type Query {
+    products: [Product]
+    product(id: ID!): Product
+
+    users: [User]
+    user(id: ID!): User
+
+    orders: [Order]
+    order(id: ID!): Order
+  }
+
+  type Mutation {
+    createProduct(
+      name: String!
+      price: Float!
+      image: String!
+      description: String
+      category: String
+      brand: String
+      stock: Int
+    ): Product
+
+    updateProduct(
+      id: ID!
+      name: String
+      price: Float
+      image: String
+      description: String
+      category: String
+      brand: String
+      stock: Int
+    ): Product
+
+    deleteProduct(id: ID!): Boolean
+
+    createUser(
+      name: String!
+      email: String!
+    ): User
+
+    deleteUser(id: ID!): Boolean
+  }
+`;

BACKEND/graphql/server.js

@@ -0,0 +1,8 @@
+import { ApolloServer } from "@apollo/server";
+import { typeDefs } from "./schema.js";
+import { resolvers } from "./resolvers.js";
+
+export const apolloServer = new ApolloServer({
+  typeDefs,
+  resolvers,
+});