Task8

package.json

@@ -8,6 +8,7 @@
   "scripts": {
     "prebuild": "rimraf dist",
     "build": "nest build",
+    "bundle": "ncc build src/lambda.ts --out dist/lambda_bundle.js",
     "format": "prettier --write \"src/**/*.ts\" \"test/**/*.ts\"",
     "start": "nest start",
     "start:dev": "nest start --watch",
@@ -21,24 +22,30 @@
     "test:e2e": "jest --config ./test/jest-e2e.json"
   },
   "dependencies": {
+    "@codegenie/serverless-express": "^4.17.0",
     "@nestjs/common": "^10.0.3",
     "@nestjs/config": "^3.0.0",
     "@nestjs/core": "^10.0.3",
     "@nestjs/jwt": "^10.1.0",
     "@nestjs/passport": "^10.0.0",
     "@nestjs/platform-express": "^10.0.3",
+    "@nestjs/typeorm": "^11.0.0",
+    "aws-lambda": "^1.0.7",
     "helmet": "^7.0.0",
     "passport": "^0.6.0",
     "passport-http": "^0.3.0",
     "passport-jwt": "^4.0.1",
     "passport-local": "^1.0.0",
+    "pg": "^8.16.3",
     "reflect-metadata": "^0.1.13",
-    "rxjs": "^7.8.1"
+    "rxjs": "^7.8.1",
+    "typeorm": "^0.3.27"
   },
   "devDependencies": {
     "@nestjs/cli": "^10.0.3",
     "@nestjs/schematics": "^10.0.1",
     "@nestjs/testing": "^10.0.3",
+    "@types/aws-lambda": "^8.10.157",
     "@types/express": "^4.17.17",
     "@types/jest": "29.5.2",
     "@types/node": "^20.3.1",
@@ -47,6 +54,7 @@
     "@types/supertest": "^2.0.12",
     "@typescript-eslint/eslint-plugin": "5.60.0",
     "@typescript-eslint/parser": "5.60.0",
+    "@vercel/ncc": "^0.38.4",
     "eslint": "8.43.0",
     "eslint-config-prettier": "^9.0.0",
     "eslint-plugin-prettier": "^5.0.0",

src/app.module.ts

@@ -1,14 +1,42 @@
 import { Module } from '@nestjs/common';
+import { TypeOrmModule } from '@nestjs/typeorm';
+import { ConfigModule, ConfigService } from '@nestjs/config';
 
 import { AppController } from './app.controller';
 
 import { CartModule } from './cart/cart.module';
 import { AuthModule } from './auth/auth.module';
 import { OrderModule } from './order/order.module';
-import { ConfigModule } from '@nestjs/config';
+import { CartEntity } from './cart/entities/cart.entity';
+import { CartItemEntity } from './cart/entities/cart-item.entity';
 
 @Module({
-  imports: [AuthModule, CartModule, OrderModule, ConfigModule.forRoot()],
+  imports: [
+    ConfigModule.forRoot({
+      isGlobal: true,
+    }),
+    TypeOrmModule.forRootAsync({
+      imports: [ConfigModule],
+      useFactory: (configService: ConfigService) => ({
+        type: 'postgres',
+        host: configService.get<string>('DB_HOST'),
+        port: configService.get<number>('DB_PORT', 5432),
+        username: configService.get<string>('DB_USERNAME'),
+        password: configService.get<string>('DB_PASSWORD'),
+        database: configService.get<string>('DB_DATABASE', 'cartdb'),
+        entities: [CartEntity, CartItemEntity],
+        synchronize: true, // Auto-create tables (for development/demo)
+        logging: false,
+        ssl: {
+          rejectUnauthorized: false, // AWS RDS uses self-signed certificates
+        },
+      }),
+      inject: [ConfigService],
+    }),
+    AuthModule,
+    CartModule,
+    OrderModule,
+  ],
   controllers: [AppController],
   providers: [],
 })

src/cart/cart.controller.ts

@@ -28,8 +28,8 @@ export class CartController {
   // @UseGuards(JwtAuthGuard)
   @UseGuards(BasicAuthGuard)
   @Get()
-  findUserCart(@Req() req: AppRequest): CartItem[] {
-    const cart = this.cartService.findOrCreateByUserId(
+  async findUserCart(@Req() req: AppRequest): Promise<CartItem[]> {
+    const cart = await this.cartService.findOrCreateByUserId(
       getUserIdFromRequest(req),
     );
 
@@ -39,12 +39,12 @@ export class CartController {
   // @UseGuards(JwtAuthGuard)
   @UseGuards(BasicAuthGuard)
   @Put()
-  updateUserCart(
+  async updateUserCart(
     @Req() req: AppRequest,
     @Body() body: PutCartPayload,
-  ): CartItem[] {
+  ): Promise<CartItem[]> {
     // TODO: validate body payload...
-    const cart = this.cartService.updateByUserId(
+    const cart = await this.cartService.updateByUserId(
       getUserIdFromRequest(req),
       body,
     );
@@ -56,16 +56,16 @@ export class CartController {
   @UseGuards(BasicAuthGuard)
   @Delete()
   @HttpCode(HttpStatus.OK)
-  clearUserCart(@Req() req: AppRequest) {
-    this.cartService.removeByUserId(getUserIdFromRequest(req));
+  async clearUserCart(@Req() req: AppRequest): Promise<void> {
+    await this.cartService.removeByUserId(getUserIdFromRequest(req));
   }
 
   // @UseGuards(JwtAuthGuard)
   @UseGuards(BasicAuthGuard)
   @Put('order')
-  checkout(@Req() req: AppRequest, @Body() body: CreateOrderDto) {
+  async checkout(@Req() req: AppRequest, @Body() body: CreateOrderDto) {
     const userId = getUserIdFromRequest(req);
-    const cart = this.cartService.findByUserId(userId);
+    const cart = await this.cartService.findByUserId(userId);
 
     if (!(cart && cart.items.length)) {
       throw new BadRequestException('Cart is empty');
@@ -83,7 +83,7 @@ export class CartController {
       address: body.address,
       total,
     });
-    this.cartService.removeByUserId(userId);
+    await this.cartService.removeByUserId(userId);
 
     return {
       order,

src/cart/cart.module.ts

@@ -1,12 +1,17 @@
 import { Module } from '@nestjs/common';
+import { TypeOrmModule } from '@nestjs/typeorm';
 
 import { OrderModule } from '../order/order.module';
 
 import { CartController } from './cart.controller';
 import { CartService } from './services';
+import { CartEntity, CartItemEntity } from './entities';
 
 @Module({
-  imports: [OrderModule],
+  imports: [
+    TypeOrmModule.forFeature([CartEntity, CartItemEntity]),
+    OrderModule,
+  ],
   providers: [CartService],
   controllers: [CartController],
 })

src/cart/entities/cart-item.entity.ts

@@ -0,0 +1,28 @@
+import { Entity, PrimaryColumn, Column, ManyToOne, JoinColumn } from 'typeorm';
+import { CartEntity } from './cart.entity';
+
+@Entity('cart_items')
+export class CartItemEntity {
+  @PrimaryColumn({ type: 'uuid' })
+  cart_id: string;
+
+  @PrimaryColumn({ type: 'varchar' })
+  product_id: string;
+
+  @Column({ type: 'int', nullable: false })
+  count: number;
+
+  // Store product details as JSON for denormalization (since products are in a different service)
+  @Column({ type: 'jsonb', nullable: true })
+  product_details: {
+    title?: string;
+    description?: string;
+    price?: number;
+  };
+
+  @ManyToOne(() => CartEntity, (cart) => cart.items, {
+    onDelete: 'CASCADE',
+  })
+  @JoinColumn({ name: 'cart_id' })
+  cart: CartEntity;
+}

src/cart/entities/cart.entity.ts

@@ -0,0 +1,35 @@
+import { Entity, PrimaryGeneratedColumn, Column, OneToMany } from 'typeorm';
+import { CartItemEntity } from './cart-item.entity';
+
+export enum CartStatus {
+  OPEN = 'OPEN',
+  ORDERED = 'ORDERED',
+}
+
+@Entity('carts')
+export class CartEntity {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Column({ type: 'varchar', nullable: false })
+  user_id: string;
+
+  @Column({
+    type: 'enum',
+    enum: CartStatus,
+    default: CartStatus.OPEN,
+  })
+  status: CartStatus;
+
+  @Column({ type: 'timestamp', default: () => 'CURRENT_TIMESTAMP' })
+  created_at: Date;
+
+  @Column({ type: 'timestamp', default: () => 'CURRENT_TIMESTAMP' })
+  updated_at: Date;
+
+  @OneToMany(() => CartItemEntity, (cartItem) => cartItem.cart, {
+    cascade: true,
+    eager: true,
+  })
+  items: CartItemEntity[];
+}

src/cart/entities/index.ts

@@ -0,0 +1,2 @@
+export { CartEntity, CartStatus } from './cart.entity';
+export { CartItemEntity } from './cart-item.entity';