feat: payment service with IPG

.env

@@ -3,7 +3,9 @@ SECRET=fDS9j269DSfd823FhdfG65
 ACCESS_TOKEN_SECERT=PNd98dsDS089ds3SDh7C5hg265SFC42bgHxTg34x
 ACCESS_TOKEN_SECERT_ADMIN=G89dsJsd90DFdsf96F8se3sgL7JB29265SFC42bgHxTg34x
 CONNECTION_STRING=
-MERCHANT_ID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
+MERCHANT_ID=250ae134-635f-4728-8415-ee9a984616e8
+IPG_TYPE=sandbox
+SITE_URL=http://localhost:3000/payment
 EMAIL_HOST=
 EMAIL_PORT=
 EMAIL_USER=
@@ -23,5 +25,5 @@ STORAGE_ENDPOINT=https://storage.iran.liara.space
 STORAGE_BUCKET=dlearn
 STORAGE_REGION=default
 
-MONGO_CONNECTION_DANAK=mongodb://root:ahh62bv6o7jndf32@srv-captain--danak-mongo-db:27017/delearn?authSource=admin
+MONGO_CONNECTION_DANAK=mongodb://root:3fd87daf47fd07183a424a998d929307@89.32.249.24:32768/delearn?authSource=admin&replicaSet=rs0&directConnection=true
 NODE_ENV=production

.env.production

@@ -3,7 +3,7 @@ SECRET=fDS9j269DSfd823FhdfG65
 ACCESS_TOKEN_SECERT=PNd98dsDS089ds3SDh7C5hg265SFC42bgHxTg34x
 ACCESS_TOKEN_SECERT_ADMIN=G89dsJsd90DFdsf96F8se3sgL7JB29265SFC42bgHxTg34x
 CONNECTION_STRING=
-MERCHANT_ID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
+MERCHANT_ID=250ae134-635f-4728-8415-ee9a984616e8
 EMAIL_HOST=
 EMAIL_PORT=
 EMAIL_USER=
@@ -24,5 +24,5 @@ STORAGE_SECRET_KEY=95e78068-ff60-41c0-82c3-71a0de0a3e2f
 STORAGE_ENDPOINT=https://storage.iran.liara.space
 STORAGE_BUCKET=dlearn
 STORAGE_REGION=default
-MONGO_CONNECTION_DANAK=mongodb://root:ahh62bv6o7jndf32@srv-captain--danak-mongo-db:27017/delearn?authSource=admin
+MONGO_CONNECTION_DANAK=mongodb://root:3fd87daf47fd07183a424a998d929307@89.32.249.24:32768/delearn?authSource=admin&replicaSet=rs0&directConnection=true
 NODE_ENV=production

src/DTO/payment.dto.ts

@@ -0,0 +1,48 @@
+import { ApiProperty } from "@nestjs/swagger";
+import { IsMongoId, IsNotEmpty } from "class-validator";
+
+export function paymentObj(payment) {
+    return {
+        id: payment.id,
+        course: payment.course,
+        authority: payment.authority,
+        amount: payment.amount,
+        user: payment.user,
+        createdAt: payment.createdAt,
+        updatedAt: payment.updatedAt,
+    };
+}
+
+export class PaymentDto {
+    @IsNotEmpty()
+    @ApiProperty({ type: String })
+    @IsMongoId({ message: 'آیدی نامعتبر است.' })
+    id: string;
+
+    @IsNotEmpty()
+    @ApiProperty({ type: "string", description: "the course id ", example: "66d9ab8b45818616a48bc322" })
+    courseId: string;
+
+    @IsNotEmpty()
+    @ApiProperty({ type: String })
+    authority: string;
+
+    @ApiProperty({ type: Number })
+    amount: number;
+
+    @ApiProperty({ type: Date })
+    createdAt: Date;
+
+    @ApiProperty({ type: Date })
+    updatedAt: Date;
+}
+
+export class CreatePaymentDto {
+    @IsNotEmpty()
+    @ApiProperty({ type: "string", description: "the course id ", example: "66d9ab8b45818616a48bc322" })
+    courseId: string;
+
+    @IsNotEmpty()
+    @ApiProperty({ type: Number, description: "the amount of payment", example: 10000 })
+    amount: number;
+}

src/app.module.ts

@@ -12,6 +12,7 @@ import { UploaderModule } from './application/common/uploader/uploader.module';
 import { CourseHeadlineModule } from './application/courseHeadline/courseHeadline.module';
 import { ConfigModule } from '@nestjs/config';
 import { CourseCategoryModule } from './application/courseCategory/courseCategory.module';
+import { PaymentModule } from './application/payment/payment.module';
 
 @Module({
   imports: [
@@ -34,6 +35,7 @@ import { CourseCategoryModule } from './application/courseCategory/courseCategor
     UploaderModule,
     CourseHeadlineModule,
     CourseCategoryModule,
+    PaymentModule,
     // ServeStaticModule.forRoot({
     //   rootPat h: join(__dirname, '..', 'public'),
     // }),

src/application/IPG/PaymentGateway.ts

@@ -0,0 +1,18 @@
+import { Injectable } from "@nestjs/common";
+import { ZarinPalGateway } from "./gateways/zarinpal";
+
+@Injectable()
+export class PaymentGateway {
+
+    constructor(
+        private zarinpalGateway: ZarinPalGateway,
+    ) { }
+
+    async requestPayment(data: any) {
+        return await this.zarinpalGateway.processPayment(data.amount, data.userId, data.callbackPath);
+    }
+
+    async verifyPayment(data: any) {
+        return await this.zarinpalGateway.verifyPayment(data.authority, data.amount);
+    }
+}

src/application/IPG/gateways/zarinpal.ts

@@ -0,0 +1,59 @@
+import { Injectable, InternalServerErrorException, Logger } from "@nestjs/common";
+import axios from "axios";
+
+@Injectable()
+export class ZarinPalGateway {
+    private logger = new Logger(ZarinPalGateway.name)
+    private gatewayApiURL: string = `https://${process.env.IPG_TYPE}.zarinpal.com/pg`;
+    private callbackURL: string = `${process.env.SITE_URL}/verify/Zarinpal`;
+    private merchantID: string = process.env.MERCHANT_ID;
+    private requestHeaders: any = {
+        'Content-Type': 'application/json',
+        Accept: 'application/json',
+    };
+
+
+    async processPayment(amount: number, userId: string, callbackPath: string) {
+        try {
+            const purchaseData = {
+                merchant_id: this.merchantID,
+                amount,
+                callback_url: `${this.callbackURL}/${callbackPath}`,
+                description: "خرید دوره",
+                currency: "IRR" as const,
+                metadata: { userId },
+            }
+
+            const response = await axios.post(`${this.gatewayApiURL}/v4/payment/request.json`, purchaseData, { headers: this.requestHeaders });
+            const { data } = response.data;
+            console.log(data)
+            return {
+                redirectUrl: `${this.gatewayApiURL}/StartPay/${data.authority}`,
+                message: data.message,
+                authority: data.authority,
+            }
+        } catch (error) {
+            console.log(error)
+            this.logger.error("error in payment process", error);
+            throw new InternalServerErrorException("error in payment process");
+        }
+    }
+
+    async verifyPayment(authority: string, amount: number) {
+        try {
+            const verifyData = {
+                merchant_id: this.merchantID,
+                amount,
+                authority,
+            }
+
+            const response = await axios.post(`${this.gatewayApiURL}/v4/payment/verify.json`, verifyData, { headers: this.requestHeaders });
+            const { data } = response.data;
+
+            return data;
+        } catch (error) {
+            this.logger.error("error in payment verification", error);
+            throw new InternalServerErrorException("error in payment verification");
+        }
+    }
+}

src/application/IPG/interface/IPG.ts

@@ -0,0 +1,12 @@
+export interface NewPaymentData {
+  amount: number;
+  description: string;
+  email: string;
+  mobile: string;
+  callbackPath: string;
+}
+
+export interface VerifyPaymentData {
+  authority: string;
+  amount: number;
+}

src/application/payment/payment.controller.ts

@@ -0,0 +1,66 @@
+import {
+    Body,
+    Controller,
+    Get,
+    HttpCode,
+    HttpStatus,
+    Post,
+    Query,
+    UseGuards,
+} from '@nestjs/common';
+import {
+    ApiBearerAuth,
+    ApiBody,
+    ApiOperation,
+    ApiQuery,
+} from '@nestjs/swagger';
+import { CurrentUser } from '../../decorators/currentUser.decorator';
+import { AuthGuard } from '../../auth/auth.guard';
+import { ApiTags } from '@nestjs/swagger';
+import { Roles } from '../../decorators/role.decorators';
+import { Role } from '../../common/eNums/role.enum';
+import { PaymentService } from './payment.service';
+import { CreatePaymentDto } from 'src/DTO/payment.dto';
+@ApiTags('payment')
+@Controller('payment')
+export class PaymentController {
+    constructor(
+        private readonly paymentService: PaymentService,
+    ) { }
+
+    @ApiOperation({
+        summary: 'ایجاد درخواست پرداخت',
+    })
+    @ApiBody({
+        type: CreatePaymentDto,
+        description: 'get body',
+    })
+    @UseGuards(AuthGuard)
+    @ApiBearerAuth()
+    @Roles(Role.User)
+    @Post()
+    @HttpCode(HttpStatus.CREATED)
+    async create(@Body() createPaymentDto: CreatePaymentDto, @CurrentUser() user) {
+        return this.paymentService.createPayment(user.id, createPaymentDto.amount, createPaymentDto.courseId);
+    }
+
+    @ApiOperation({
+        summary: 'تایید پرداخت',
+    })
+    @ApiQuery({
+        name: 'Authority',
+        type: 'string',
+        description: 'get authority',
+    })
+    @ApiQuery({
+        name: 'status',
+        type: 'string',
+        description: 'get status',
+    })
+    @Get('/verify/Zarinpal/cart')
+    async verifyPayment(@Query('Authority') authority: string, @Query('Status') status: string) {
+        console.log({ authorityInController: authority, status })
+        return this.paymentService.verifyPayment(authority, status);
+    }
+
+}

src/application/payment/payment.module.ts

@@ -0,0 +1,24 @@
+import { Logger, Module } from '@nestjs/common';
+import { UserModule } from '../user/user.module';
+import { UserDataAccess } from '../../dataAccess/user.dataAccess';
+import { PaymentService } from './payment.service';
+import { PaymentController } from './payment.controller';
+import { PaymentDataAccess } from 'src/dataAccess/payment.dataAccess';
+import { PaymentGateway } from '../IPG/PaymentGateway';
+import { ZarinPalGateway } from '../IPG/gateways/zarinpal';
+
+@Module({
+  imports: [
+    UserModule,
+  ],
+  controllers: [PaymentController],
+  providers: [
+    ZarinPalGateway,
+    PaymentDataAccess,
+    PaymentGateway,
+    PaymentService,
+    UserDataAccess,
+  ],
+  exports: []
+})
+export class PaymentModule { }

src/application/payment/payment.service.ts

@@ -0,0 +1,63 @@
+import { Injectable, Logger } from "@nestjs/common";
+import { PaymentDataAccess } from "../../dataAccess/payment.dataAccess";
+import { startSession } from "mongoose";
+import { PaymentGateway } from "../IPG/PaymentGateway";
+import { UserDataAccess } from "../../dataAccess/user.dataAccess";
+
+@Injectable()
+export class PaymentService {
+  private readonly logger = new Logger(PaymentService.name);
+  constructor(
+    private readonly paymentDataAccess: PaymentDataAccess,
+    private readonly paymentGateway: PaymentGateway,
+    private readonly userDataAccess: UserDataAccess,
+  ) { }
+
+  async createPayment(userId: string, amount: number, courseId: string) {
+    const session = await startSession();
+    session.startTransaction();
+    try {
+      const paymentData = await this.paymentGateway.requestPayment({ amount, userId, callbackPath: "cart" });
+      console.log(paymentData)
+      if (!paymentData) {
+        throw new Error("Error in payment process");
+      }
+
+      const payment = await this.paymentDataAccess.createPayment(
+        userId,
+        amount,
+        courseId,
+        paymentData.authority,
+        session
+      );
+      console.log({ payment })
+      await session.commitTransaction();
+      await session.endSession();
+      return { payment: payment, paymentData }
+    } catch (error) {
+      await session.abortTransaction();
+      await session.endSession();
+      this.logger.warn(error);
+    }
+  }
+
+
+  async verifyPayment(authority: string, status: string) {
+    console.log({ authorityInService: authority })
+    const paymentData = await this.paymentDataAccess.getPaymentByAuthority(authority);
+    console.log({ paymentData })
+    if (!paymentData) {
+      throw new Error("payment not found");
+    }
+    const verifyData = await this.paymentGateway.verifyPayment({ authority, amount: paymentData.amount });
+    if (verifyData.code === 100 || verifyData.code === 101) {
+      const registerCourse = await this.userDataAccess.registerCourse(paymentData.userId, paymentData.courseId);
+      console.log(registerCourse)
+      if (!registerCourse.success) {
+        throw new Error("error in register course");
+      }
+      return { success: true, payment: paymentData, verifyData }
+    }
+
+  }
+}

src/application/user/user.controller.ts

@@ -110,45 +110,45 @@ export class UserController {
     }
   }
 
-  @ApiOperation({
-    summary: 'افزایش موجودی کیف پول',
-  })
-  @ApiBody({
-    type: AddBalanceDto,
-    description: 'get body',
-  })
-  @UseGuards(AuthGuard)
-  @Roles(Role.User)
-  @ApiBearerAuth()
-  @Post('add')
-  addBalance(@CurrentUser() user, @Body() addBalanceDto: AddBalanceDto) {
-    return this.userService.addBalance(
-      user.id,
-      addBalanceDto.amount,
-      addBalanceDto.paymentNumber,
-      addBalanceDto.reason,
-    );
-  }
+  // @ApiOperation({
+  //   summary: 'افزایش موجودی کیف پول',
+  // })
+  // @ApiBody({
+  //   type: AddBalanceDto,
+  //   description: 'get body',
+  // })
+  // @UseGuards(AuthGuard)
+  // @Roles(Role.User)
+  // @ApiBearerAuth()
+  // @Post('add')
+  // addBalance(@CurrentUser() user, @Body() addBalanceDto: AddBalanceDto) {
+  //   return this.userService.addBalance(
+  //     user.id,
+  //     addBalanceDto.amount,
+  //     addBalanceDto.paymentNumber,
+  //     addBalanceDto.reason,
+  //   );
+  // }
 
-  @ApiOperation({
-    summary: 'موجودی کیف پول',
-  })
-  @UseGuards(AuthGuard)
-  @Roles(Role.User)
-  @ApiBearerAuth()
-  @Get('balance')
-  getBalance(@CurrentUser() user) {
-    return this.userService.getBalance(user.id);
-  }
+  // @ApiOperation({
+  //   summary: 'موجودی کیف پول',
+  // })
+  // @UseGuards(AuthGuard)
+  // @Roles(Role.User)
+  // @ApiBearerAuth()
+  // @Get('balance')
+  // getBalance(@CurrentUser() user) {
+  //   return this.userService.getBalance(user.id);
+  // }
 
-  @ApiOperation({
-    summary: 'لیست تراکنش ها',
-  })
-  @UseGuards(AuthGuard)
-  @Roles(Role.User)
-  @ApiBearerAuth()
-  @Get('payments')
-  getPayments(@CurrentUser() user) {
-    return this.userService.getPayments(user.id);
-  }
+  // @ApiOperation({
+  //   summary: 'لیست تراکنش ها',
+  // })
+  // @UseGuards(AuthGuard)
+  // @Roles(Role.User)
+  // @ApiBearerAuth()
+  // @Get('payments')
+  // getPayments(@CurrentUser() user) {
+  //   return this.userService.getPayments(user.id);
+  // }
 }

src/application/user/user.service.ts

@@ -150,40 +150,40 @@ export class UserService {
     );
   }
 
-  async addBalance(
-    userId: string,
-    amount: number,
-    paymentNumber: string,
-    reason: string,
-  ) {
-    const user = await this.userDataAccess.findOne(userId);
-    const payment = await this.paymentDataAccess.createPayment(
-      userId,
-      amount,
-      paymentNumber,
-      reason,
-    );
-    user.walletBalance += amount;
-    return await user.save();
-  }
+  // async addBalance(
+  //   userId: string,
+  //   amount: number,
+  //   paymentNumber: string,
+  //   reason: string,
+  // ) {
+  //   const user = await this.userDataAccess.findOne(userId);
+  //   const payment = await this.paymentDataAccess.createPayment(
+  //     userId,
+  //     amount,
+  //     paymentNumber,
+  //     reason,
+  //   );
+  //   user.walletBalance += amount;
+  //   return await user.save();
+  // }
 
-  async getBalance(userId: string): Promise<number> {
-    const user = await this.userDataAccess.findOne(userId);
-    return user.walletBalance;
-  }
+  // async getBalance(userId: string): Promise<number> {
+  //   const user = await this.userDataAccess.findOne(userId);
+  //   return user.walletBalance;
+  // }
 
-  async getPayments(userId: string) {
-    const user = await this.userDataAccess.findOne(userId);
-    if (!user) {
-      throw new HttpException(
-        {
-          status: HttpStatus.NOT_FOUND,
-          error: 'کاربر وجود ندارد',
-        },
-        HttpStatus.NOT_FOUND,
-      );
-    }
-    const payments = await this.paymentDataAccess.getPaymentsByUserId(userId);
-    return payments;
-  }
+  // async getPayments(userId: string) {
+  //   const user = await this.userDataAccess.findOne(userId);
+  //   if (!user) {
+  //     throw new HttpException(
+  //       {
+  //         status: HttpStatus.NOT_FOUND,
+  //         error: 'کاربر وجود ندارد',
+  //       },
+  //       HttpStatus.NOT_FOUND,
+  //     );
+  //   }
+  //   const payments = await this.paymentDataAccess.getPaymentsByUserId(userId);
+  //   return payments;
+  // }
 }

src/common/eNums/paymentStatus.enum.ts

@@ -0,0 +1,5 @@
+export enum PaymentStatus {
+    Pending = "Pending",
+    Cancelled = "Cancelled",
+    Completed = "Completed",
+}

src/dataAccess/course.dataAccess.ts

@@ -217,6 +217,12 @@ export class CourseDataAccess {
     return result;
   }
 
+
+  async getUserCourses(user: string): Promise<Course[]> {
+    const result = await Models.Course.find({ studentIds: user });
+    return result
+  }
+
   async deleteCourse(courseId: string): Promise<Course> {
     const result = await Models.Course.findByIdAndDelete(courseId);
     return result;

src/dataAccess/payment.dataAccess.ts

@@ -2,8 +2,10 @@ import Models from "../models";
 import Payment from "../models/payment.model";
 
 export class PaymentDataAccess {
-  async createPayment(userId: string, amount: number, paymentNumber: string,reason:string):Promise<Payment> {
-    const payment = Models.Payment.create({ userId, amount, paymentNumber,reason });
+  async createPayment(userId: string, amount: number, courseId: string, authority: string, session: any): Promise<Payment> {
+    const paymentDoc = await Models.Payment.create([{ userId, amount, courseId, authority }], { session });
+    console.log({ paymentDoc });
+    const payment = paymentDoc.map(doc => doc.toObject())[0];
     return payment;
   }
 
@@ -12,6 +14,12 @@ export class PaymentDataAccess {
     return payment;
   }
 
+  async getPaymentByAuthority(authority: string): Promise<Payment | null> {
+    console.log({ authority })
+    const payment = await Models.Payment.findOne({ authority });
+    console.log(payment, "ssssss")
+    return payment;
+  }
   async getPaymentsByUserId(userId: string): Promise<Payment[]> {
     const payments = await Models.Payment.find({ userId });
     return payments;

src/dataAccess/purchase.dataAccess.ts

@@ -0,0 +1,25 @@
+import { Purchase } from "../models/schemas/purchase.schema";
+import Models from "../models";
+
+export class PurchaseDataAccess {
+  async createPurchase(userId: string, courseId: string, paymentId: string): Promise<Purchase> {
+    const purchase = Models.Purchase.create({ userId, courseId, paymentId });
+    return purchase;
+  }
+
+  async getPurchase(purchaseId: string): Promise<Purchase | null> {
+    const purchase = await Models.Purchase.findById(purchaseId);
+    return purchase;
+  }
+
+  async getPurchasesByUserId(userId: string): Promise<Purchase[]> {
+    const purchase = await Models.Purchase.find({ userId });
+    return purchase;
+  }
+
+  async getPurchases(): Promise<Purchase[]> {
+    const purchase = await Models.Purchase.find();
+    return purchase;
+  }
+}
+

src/dataAccess/user.dataAccess.ts

@@ -112,6 +112,6 @@ export class UserDataAccess {
     course.studentIds.push(userId);
     await user.save();
     await course.save();
-    return { message: 'ثبت نام با موفقیت انجام شد' };
+    return { message: 'ثبت نام با موفقیت انجام شد', success: true };
   }
 }

src/main.ts

@@ -5,7 +5,7 @@ import mongoose from 'mongoose';
 import * as dotenv from 'dotenv';
 import { DocumentBuilder, SwaggerModule } from '@nestjs/swagger';
 import * as swaggerConfig from './config/swagger.json';
-import { ValidationPipe } from '@nestjs/common';
+import { Logger, ValidationPipe } from '@nestjs/common';
 import { NestExpressApplication } from '@nestjs/platform-express';
 import paths from './config/paths';
 dotenv.config();
@@ -61,5 +61,6 @@ async function bootstrap() {
   const document = SwaggerModule.createDocument(app, config);
   SwaggerModule.setup('api/v1', app, document);
   await app.listen(3000, '0.0.0.0');
+  Logger.log(`Server api docs running on http://localhost:3000/api/v1`, 'Boostrap');
 }
 bootstrap();

src/models/index.ts

@@ -19,6 +19,7 @@ import UserDiscount from './userDiscount.model';
 import Rate from './rate.model';
 import Payment from './payment.model';
 import Settings from './settings.model';
+import Purchase from './Purchase.model';
 
 const Models = {
   User,
@@ -42,6 +43,7 @@ const Models = {
   CourseHeadlineComment,
   Rate,
   Payment,
+  Purchase
 };
 
 export default Models;

src/models/purchase.model.ts

@@ -0,0 +1,12 @@
+import mongoose from 'mongoose';
+import { softDeletePlugin, SoftDeleteModel } from 'soft-delete-plugin-mongoose';
+import { cleanJson } from './plugins';
+import { Purchase, PurchaseSchema } from './schemas/purchase.schema';
+
+PurchaseSchema.plugin(softDeletePlugin);
+PurchaseSchema.plugin(cleanJson);
+const Purchase = mongoose.model<Purchase, SoftDeleteModel<Purchase>>(
+  'purchases',
+  PurchaseSchema,
+);
+export default Purchase;

src/models/schemas/payment.schema.ts

@@ -1,5 +1,6 @@
 
 import mongoose from "mongoose";
+import { PaymentStatus } from "src/common/eNums/paymentStatus.enum";
 
 export const PaymentSchema = new mongoose.Schema({
   userId: {
@@ -7,17 +8,27 @@ export const PaymentSchema = new mongoose.Schema({
     ref: 'users',
     required: true
   },
+  courseId: {
+    type: mongoose.Types.ObjectId,
+    ref: 'courses',
+    required: true
+  },
+  authority: {
+    type: String,
+    required: true
+  },
   amount: {
     type: Number,
     required: true
   },
-  paymentNumber: {
+  transactionNumber: {
     type: String,
-    required: true,
+    default: null
   },
-  reason: {
+  paymentStatus: {
     type: String,
-    enum: ['deposit', 'withdrawal'],
+    enum: PaymentStatus,
+    default: PaymentStatus.Pending,
     required: true
   },
 },
@@ -30,8 +41,10 @@ export const PaymentSchema = new mongoose.Schema({
 export interface Payment extends mongoose.Document {
   userId: mongoose.Types.ObjectId;
   amount: number;
-  paymentNumber: string;
-  reason: 'deposit' | 'withdrawal';
+  authority: string;
+  courseId: mongoose.Types.ObjectId;
+  transactionNumber: string;
+  paymentStatus: PaymentStatus;
   createdAt: Date;
   updatedAt: Date;
 }

src/models/schemas/purchase.schema.ts

@@ -0,0 +1,33 @@
+
+import mongoose from "mongoose";
+
+export const PurchaseSchema = new mongoose.Schema({
+  userId: {
+    type: mongoose.Types.ObjectId,
+    ref: 'users',
+    required: true
+  },
+  courseId: {
+    type: mongoose.Types.ObjectId,
+    ref: 'courses',
+    required: true
+  },
+  paymentId: {
+    type: mongoose.Types.ObjectId,
+    ref: 'payments',
+    required: true
+  },
+},
+  {
+    collection: 'purchases',
+    timestamps: true,
+  },
+);
+
+export interface Purchase extends mongoose.Document {
+  userId: mongoose.Types.ObjectId;
+  courseId: mongoose.Types.ObjectId;
+  paymentId: mongoose.Types.ObjectId;
+  createdAt: Date;
+  updatedAt: Date;
+}