feat: refactor cart module to use TypeORM for database interactions

env.example

@@ -4,4 +4,14 @@ APP_PORT=4000
 AUTH_USERNAME=yourGithubLogin ### It should be your github username
 AUTH_PASSWORD=TEST_PASSWORD
 APP_URL=http://localhost:4000
-###
+###
+
+### Database configuration (local development)
+DB_HOST=localhost
+DB_PORT=5432
+DB_NAME=cartdb
+DB_USERNAME=postgres
+DB_PASSWORD=postgres
+### For AWS Lambda, DB_SECRET_ARN is set by CDK and DB_PASSWORD is retrieved from Secrets Manager
+# DB_SECRET_ARN=arn:aws:secretsmanager:us-east-1:ACCOUNT_ID:secret:...
+DB_SSL=false

package.json

@@ -6,7 +6,7 @@
   "private": true,
   "license": "UNLICENSED",
   "scripts": {
-    "prebuild": "rimraf dist",
+    "prebuild": "./node_modules/.bin/rimraf dist",
     "build": "nest build",
     "format": "prettier --write \"src/**/*.ts\" \"test/**/*.ts\"",
     "start": "nest start",
@@ -21,29 +21,37 @@
     "test:e2e": "jest --config ./test/jest-e2e.json"
   },
   "dependencies": {
+    "@aws-sdk/client-secrets-manager": "^3.1045.0",
     "@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": "^10.0.2",
+    "@vendia/serverless-express": "^4.12.6",
+    "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": "^8.20.0",
     "reflect-metadata": "^0.1.13",
-    "rxjs": "^7.8.1"
+    "rxjs": "^7.8.1",
+    "typeorm": "^0.3.29"
   },
   "devDependencies": {
     "@nestjs/cli": "^10.0.3",
     "@nestjs/schematics": "^10.0.1",
     "@nestjs/testing": "^10.0.3",
+    "@types/aws-lambda": "^8.10.161",
     "@types/express": "^4.17.17",
     "@types/jest": "29.5.2",
-    "@types/node": "^20.3.1",
+    "@types/node": "^22.19.19",
     "@types/passport-jwt": "^3.0.8",
     "@types/passport-local": "^1.0.35",
+    "@types/pg": "^8.20.0",
     "@types/supertest": "^2.0.12",
     "@typescript-eslint/eslint-plugin": "5.60.0",
     "@typescript-eslint/parser": "5.60.0",
@@ -58,7 +66,7 @@
     "ts-loader": "^9.4.3",
     "ts-node": "10.9.1",
     "tsconfig-paths": "^4.2.0",
-    "typescript": "^5.1.3"
+    "typescript": "^5.9.3"
   },
   "jest": {
     "moduleFileExtensions": [

src/app.module.ts

@@ -6,9 +6,16 @@ import { CartModule } from './cart/cart.module';
 import { AuthModule } from './auth/auth.module';
 import { OrderModule } from './order/order.module';
 import { ConfigModule } from '@nestjs/config';
+import { DatabaseModule } from './database/database.module';
 
 @Module({
-  imports: [AuthModule, CartModule, OrderModule, ConfigModule.forRoot()],
+  imports: [
+    ConfigModule.forRoot({ isGlobal: true }),
+    DatabaseModule,
+    AuthModule,
+    CartModule,
+    OrderModule,
+  ],
   controllers: [AppController],
   providers: [],
 })

src/auth/strategies/basic.strategy.ts

@@ -1,4 +1,4 @@
-import { Injectable, UnauthorizedException } from '@nestjs/common';
+import { Injectable, UnauthorizedException, Inject } from '@nestjs/common';
 import { PassportStrategy } from '@nestjs/passport';
 
 import { BasicStrategy as Strategy } from 'passport-http';
@@ -7,7 +7,7 @@ import { AuthService } from '../auth.service';
 
 @Injectable()
 export class BasicStrategy extends PassportStrategy(Strategy) {
-  constructor(private authService: AuthService) {
+  constructor(@Inject(AuthService) private authService: AuthService) {
     super();
   }
 

src/cart/cart.controller.ts

@@ -13,11 +13,21 @@ import {
 import { BasicAuthGuard } from '../auth';
 import { Order, OrderService } from '../order';
 import { AppRequest, getUserIdFromRequest } from '../shared';
-import { calculateCartTotal } from './models-rules';
 import { CartService } from './services';
-import { CartItem } from './models';
+import { CartItemEntity, ProductData } from './entities/cart-item.entity';
 import { CreateOrderDto, PutCartPayload } from 'src/order/type';
 
+type FrontendCartItem = { product: ProductData; count: number };
+
+function toFrontendItems(items: CartItemEntity[]): FrontendCartItem[] {
+  return items
+    .filter((item) => item.product_data)
+    .map((item) => ({
+      product: item.product_data as ProductData,
+      count: item.count,
+    }));
+}
+
 @Controller('api/profile/cart')
 export class CartController {
   constructor(
@@ -28,66 +38,63 @@ export class CartController {
   // @UseGuards(JwtAuthGuard)
   @UseGuards(BasicAuthGuard)
   @Get()
-  findUserCart(@Req() req: AppRequest): CartItem[] {
-    const cart = this.cartService.findOrCreateByUserId(
+  async findUserCart(@Req() req: AppRequest): Promise<FrontendCartItem[]> {
+    const cart = await this.cartService.findOrCreateByUserId(
       getUserIdFromRequest(req),
     );
 
-    return cart.items;
+    return toFrontendItems(cart.items);
   }
 
   // @UseGuards(JwtAuthGuard)
   @UseGuards(BasicAuthGuard)
   @Put()
-  updateUserCart(
+  async updateUserCart(
     @Req() req: AppRequest,
     @Body() body: PutCartPayload,
-  ): CartItem[] {
+  ): Promise<FrontendCartItem[]> {
     // TODO: validate body payload...
-    const cart = this.cartService.updateByUserId(
+    const cart = await this.cartService.updateByUserId(
       getUserIdFromRequest(req),
       body,
     );
 
-    return cart.items;
+    return toFrontendItems(cart.items);
   }
 
   // @UseGuards(JwtAuthGuard)
   @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');
     }
 
     const { id: cartId, items } = cart;
-    const total = calculateCartTotal(items);
     const order = this.orderService.create({
       userId,
       cartId,
-      items: items.map(({ product, count }) => ({
-        productId: product.id,
+      items: items.map(({ product_id, count }) => ({
+        productId: product_id,
         count,
       })),
       address: body.address,
-      total,
+      total: 0,
     });
-    this.cartService.removeByUserId(userId);
+    await this.cartService.removeByUserId(userId);
 
-    return {
-      order,
-    };
+    return { order };
   }
 
   @UseGuards(BasicAuthGuard)

src/cart/cart.module.ts

@@ -1,12 +1,18 @@
 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 } from './entities/cart.entity';
+import { CartItemEntity } from './entities/cart-item.entity';
 
 @Module({
-  imports: [OrderModule],
+  imports: [
+    OrderModule,
+    TypeOrmModule.forFeature([CartEntity, CartItemEntity]),
+  ],
   providers: [CartService],
   controllers: [CartController],
 })

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

@@ -0,0 +1,28 @@
+import { Entity, Column, ManyToOne, JoinColumn, PrimaryColumn } from 'typeorm';
+import { CartEntity } from './cart.entity';
+
+export type ProductData = {
+  id: string;
+  title: string;
+  description: string;
+  price: number;
+};
+
+@Entity('cart_items')
+export class CartItemEntity {
+  @PrimaryColumn({ name: 'cart_id', type: 'uuid' })
+  cart_id!: string;
+
+  @PrimaryColumn({ type: 'varchar' })
+  product_id!: string;
+
+  @Column({ type: 'int' })
+  count!: number;
+
+  @Column({ type: 'simple-json', nullable: true })
+  product_data!: ProductData | null;
+
+  @ManyToOne(() => CartEntity, (cart) => cart.items, { onDelete: 'CASCADE' })
+  @JoinColumn({ name: 'cart_id' })
+  cart!: CartEntity;
+}

src/cart/entities/cart.entity.ts

@@ -0,0 +1,38 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  OneToMany,
+  CreateDateColumn,
+  UpdateDateColumn,
+} 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;
+
+  @CreateDateColumn()
+  created_at: Date;
+
+  @UpdateDateColumn()
+  updated_at: Date;
+
+  @OneToMany(() => CartItemEntity, (item) => item.cart, {
+    cascade: true,
+    eager: true,
+  })
+  items: CartItemEntity[];
+}

src/cart/entities/index.ts

@@ -0,0 +1,2 @@
+export * from './cart.entity';
+export * from './cart-item.entity';