[NestJS] Milestone 6: Plot twist! Special treat to Wakandians.

README.md

@@ -436,7 +436,13 @@ This milestone introduced other two use cases: add the occupation data, and add
 
 ### Milestone 6: Plot twist!
 
-In this milestone, we will need to change our business logic to skip wakandians from passing address verification, and we will automatically send a welcome email as the final step of the KYC process, including a special promo code to buy vibranium for wakandians.
+In this milestone, we will need to change our business logic to skip wakandians from passing address verification, and we will automatically send a welcome email as the final step of the KYC process, including a special promo code to buy vibranium for wakandians. So we're going to apply the following changes:
+
+1. Reject any address verification webhook call for wakandians.
+2. Allow `KYCStatus` to transition from `KYCIDVerified` to `KYCBackgroundCheckPassed` or `KYCBackgroundCheckRequiresManualReview` for wakandians.
+3. Trigger the automated background check after a successful ID verification for wakandians.
+4. Trigger the welcome email after the background check has been passed. For wakandians, generate and include promo codes to buy vibranium.
+5. When the email is sent, no matter if it succeeds or not, the result is registered and the profile is moved to the final `KYCCompleted` state.
 
 TBD!
 

kyc-nest/.env

@@ -2,3 +2,5 @@ OFAC_PROXY_URL="http://localhost:8000"
 OFAC_PROXY_API_KEY="1234567890"
 PEP_PROXY_URL="http://localhost:8000"
 PEP_PROXY_API_KEY="1234567890"
+MAIL_SERVICE_URL="http://localhost:8000"
+MAIL_SERVICE_API_KEY="1234567890"

kyc-nest/src/kyc/kyc.module.ts

@@ -1,11 +1,12 @@
 import { Module } from '@nestjs/common';
 import { KYCService } from './kyc.service';
 import { KYCController } from './kyc.controller';
-import { ProfileModule } from 'src/profile/profile.module';
 import { ConfigModule } from '@nestjs/config';
+import { ProfileModule } from 'src/profile/profile.module';
+import { PromoCodeModule } from 'src/promo-code/promo-code-module';
 
 @Module({
- imports: [ProfileModule, ConfigModule.forRoot()],
+ imports: [ProfileModule, PromoCodeModule, ConfigModule.forRoot()],
  providers: [KYCService],
  controllers: [KYCController],
 })

kyc-nest/src/kyc/kyc.service.ts

@@ -7,11 +7,13 @@ import {
 import { ProfileService } from '../profile/profile.service';
 import { Profile } from 'src/profile/profile.entity';
 import { ConfigService } from '@nestjs/config';
+import { PromoCodeService } from '../promo-code/promo-code.service';
 
 @Injectable()
 export class KYCService {
  constructor(
  private readonly profileService: ProfileService,
+ private readonly promoCodeService: PromoCodeService,
  private configService: ConfigService,
  ) {}
 
@@ -29,6 +31,12 @@ export class KYCService {
  idVerificationId: message.verificationId,
  idVerifiedAt: message.timestamp,
  });
+
+ // Trigger the automated background check for profiles that skip the address verification
+ const profile = await this.profileService.findById(userId);
+ if (profile.skipsAddressVerification()) {
+ this.performBackgroundCheck(userId);
+ }
  } else if (message.result === 'rejected') {
  await this.profileService.update(userId, {
  kycStatus: 'KYCIDRejected',
@@ -48,6 +56,12 @@ export class KYCService {
 
  console.log('Received address verification webhook message:', message);
 
+ // Wakandians cannot legally share their address or location
+ const profile = await this.profileService.findById(userId);
+ if (profile.skipsAddressVerification()) {
+ throw new Error('Invalid address verification trial');
+ }
+
  if (message.result === 'success') {
  await this.profileService.update(userId, {
  kycStatus: 'KYCAddressVerified',
@@ -77,6 +91,8 @@ export class KYCService {
  backgroundCheckManualValidatorId: validatorId,
  backgroundCheckPassedAt: timestamp,
  });
+
+ await this.sendWelcomeEmail(userId);
  } else {
  await this.profileService.update(userId, {
  kycStatus: 'KYCBackgroundCheckRejected',
@@ -97,6 +113,8 @@ export class KYCService {
  kycStatus: 'KYCBackgroundCheckPassed',
  backgroundCheckPassedAt: new Date().toISOString(),
  });
+
+ await this.sendWelcomeEmail(profile.id);
  } else {
  await this.profileService.update(profileId, {
  kycStatus: 'KYCBackgroundCheckRequiresManualReview',
@@ -152,4 +170,51 @@ export class KYCService {
  const pepData = await pepResponse.json();
  return pepData.result === 'clear';
  }
+
+ private async sendWelcomeEmail(userId: string): Promise<void> {
+ const mailServiceURL = this.configService.get<string>('MAIL_SERVICE_URL');
+ const mailServiceAPIKey = this.configService.get<string>(
+ 'MAIL_SERVICE_API_KEY',
+ );
+
+ const profile = await this.profileService.findById(userId);
+ const { id, firstName, lastName, email } = profile;
+ const profileData = {
+ id,
+ firstName,
+ lastName,
+ email,
+ };
+
+ const extraData = {};
+ if (profile.country === 'Wakanda') {
+ const promoCode = await this.promoCodeService.create(profile);
+ extraData['templateId'] = 'WakandianSpecialKYCWelcomeEmailTemplate';
+ extraData['promoCode'] = promoCode.code;
+ } else {
+ extraData['templateId'] = 'KYCWelcomeEmailTemplate';
+ }
+
+ const mailServiceResponse = await fetch(mailServiceURL, {
+ method: 'POST',
+ headers: { Authorization: `Bearer ${mailServiceAPIKey}` },
+ body: JSON.stringify({
+ origin: 'kycService',
+ ...extraData,
+ ...profileData,
+ }),
+ });
+
+ const response = await mailServiceResponse.json();
+ const resultStatus = {};
+ if (response.result === 'delivered') {
+ resultStatus['welcomeEmailDeliveredAt'] = new Date().toISOString();
+ } else {
+ resultStatus['welcomeEmailDeliveryFailedAt'] = new Date().toISOString();
+ }
+ this.profileService.update(userId, {
+ kycStatus: 'KYCCompleted',
+ ...resultStatus,
+ });
+ }
 }

kyc-nest/src/profile/profile.entity.ts

@@ -1,5 +1,6 @@
-import { Entity, PrimaryGeneratedColumn, Column, OneToMany } from 'typeorm';
+import { Entity, PrimaryGeneratedColumn, Column, OneToMany, OneToOne } from 'typeorm';
 import { Relative } from '../relative/relative.entity';
+import { PromoCode } from '../promo-code/promo-code.entity';
 
 export type KYCStatus =
  | 'KYCPending'
@@ -9,7 +10,8 @@ export type KYCStatus =
  | 'KYCAddressRejected'
  | 'KYCBackgroundCheckPassed'
  | 'KYCBackgroundCheckRequiresManualReview'
- | 'KYCBackgroundCheckRejected';
+ | 'KYCBackgroundCheckRejected'
+ | 'KYCCompleted';
 
 export enum IncomeSource {
  Salary = 'Salary',
@@ -23,6 +25,8 @@ export enum IncomeSource {
  SocialSecurity = 'Social Security',
 }
 
+const countriesWithNoAddressVerifications = ['Wakanda'];
+
 @Entity()
 export class Profile {
  @PrimaryGeneratedColumn()
@@ -109,6 +113,21 @@ export class Profile {
  @Column({ nullable: true })
  backgroundCheckRejectedAt?: string;
 
+ @Column({ nullable: true })
+ welcomeEmailDeliveredAt?: string;
+
+ @Column({ nullable: true })
+ welcomeEmailDeliveryFailedAt?: string;
+
  @OneToMany(() => Relative, (relative) => relative.profile, { cascade: true })
  relatives: Relative[];
+
+ @OneToOne(() => PromoCode, (promoCode) => promoCode.profile, {
+ cascade: true,
+ })
+ promoCode: PromoCode;
+
+ public skipsAddressVerification(): boolean {
+ return countriesWithNoAddressVerifications.includes(this.country);
+ }
 }

kyc-nest/src/profile/profile.service.ts

@@ -25,7 +25,7 @@ export class ProfileService {
 
  if (
  profileData.kycStatus &&
- !this.isValidTransition(profile.kycStatus, profileData.kycStatus)
+ !this.isValidTransition(profile, profileData.kycStatus)
  ) {
  throw new BadRequestException(
  `Invalid status transition from '${profile.kycStatus}' to '${profileData.kycStatus}'`,
@@ -42,7 +42,7 @@ export class ProfileService {
  async findById(id: string): Promise<Profile> {
  const options: FindOneOptions<Profile> = {
  where: { id },
- relations: ['relatives'],
+ relations: ['relatives', 'promoCode'],
  };
 
  const profile = await this.profileRepository.findOne(options);
@@ -52,34 +52,41 @@ export class ProfileService {
  return profile;
  }
 
- private isValidTransition(
- currentState: KYCStatus,
- newState: KYCStatus,
- ): boolean {
- return this.allowedTransitions(currentState).includes(newState);
+ private isValidTransition(profile: Profile, newState: KYCStatus): boolean {
+ return this.allowedTransitions(profile).includes(newState);
  }
 
- private allowedTransitions(currentState: KYCStatus): KYCStatus[] {
- switch (currentState) {
+ private allowedTransitions(profile: Profile): KYCStatus[] {
+ const AddressVerificationTargetStates: KYCStatus[] = [
+ 'KYCAddressVerified',
+ 'KYCAddressRejected',
+ ];
+ const AutomatedBackgroundCheckTargetStates: KYCStatus[] = [
+ 'KYCBackgroundCheckPassed',
+ 'KYCBackgroundCheckRequiresManualReview',
+ ];
+ switch (profile.kycStatus) {
  // Initial state
  case 'KYCPending':
  return ['KYCIDVerified', 'KYCIDRejected'];
  // Step 1: ID Verified, waiting for address verification
  case 'KYCIDVerified':
- return ['KYCAddressVerified', 'KYCAddressRejected'];
+ if (profile.skipsAddressVerification()) {
+ return AutomatedBackgroundCheckTargetStates;
+ } else {
+ return AddressVerificationTargetStates;
+ }
  // Step 2: Address verified, waiting for background check
  case 'KYCAddressVerified':
- return [
- 'KYCBackgroundCheckPassed',
- 'KYCBackgroundCheckRequiresManualReview',
- ];
+ return AutomatedBackgroundCheckTargetStates;
  // Step 3: Background check suspicious, waiting for manual review
  case 'KYCBackgroundCheckRequiresManualReview':
  return ['KYCBackgroundCheckPassed', 'KYCBackgroundCheckRejected'];
  // Step 4: Background check passed, waiting for risk assessment
  case 'KYCBackgroundCheckPassed':
- return [];
+ return ['KYCCompleted'];
  // Final states
+ case 'KYCCompleted':
  case 'KYCIDRejected':
  case 'KYCAddressRejected':
  case 'KYCBackgroundCheckRejected':

kyc-nest/src/promo-code/promo-code-module.ts

@@ -0,0 +1,12 @@
+import { Module } from '@nestjs/common';
+import { TypeOrmModule } from '@nestjs/typeorm';
+import { ProfileModule } from '../profile/profile.module';
+import { PromoCode } from './promo-code.entity';
+import { PromoCodeService } from './promo-code.service';
+
+@Module({
+ imports: [TypeOrmModule.forFeature([PromoCode]), ProfileModule],
+ providers: [PromoCodeService],
+ exports: [PromoCodeService],
+})
+export class PromoCodeModule {}

kyc-nest/src/promo-code/promo-code.entity.ts

@@ -0,0 +1,16 @@
+import { Entity, PrimaryGeneratedColumn, Column, ManyToOne } from 'typeorm';
+import { Profile } from '../profile/profile.entity';
+
+@Entity()
+export class PromoCode {
+ @PrimaryGeneratedColumn()
+ id: string;
+
+ @Column()
+ code: string;
+
+ @ManyToOne(() => Profile, (profile) => profile.relatives, {
+ onDelete: 'CASCADE',
+ })
+ profile: Profile;
+}

kyc-nest/src/promo-code/promo-code.service.ts

@@ -0,0 +1,24 @@
+import { Injectable } from '@nestjs/common';
+import { InjectRepository } from '@nestjs/typeorm';
+import { Repository } from 'typeorm';
+import { ProfileService } from '../profile/profile.service';
+import { PromoCode } from './promo-code.entity';
+import { Profile } from 'src/profile/profile.entity';
+import * as crypto from 'crypto';
+
+@Injectable()
+export class PromoCodeService {
+ constructor(
+ private readonly profileService: ProfileService,
+ @InjectRepository(PromoCode)
+ private relativeRepository: Repository<PromoCode>,
+ ) {}
+
+ async create(profile: Profile): Promise<PromoCode> {
+ const code = crypto.randomBytes(20).toString('hex');
+ const promoCode = this.relativeRepository.create({ code });
+ promoCode.profile = profile;
+
+ return this.relativeRepository.save(promoCode);
+ }
+}

mock-server.js

@@ -8,7 +8,8 @@ const server = http.createServer((req, res) => {
  console.log(chunk.toString());
  });
  let response = {
- result: 'clear'
+ //result: 'clear'
+ result: 'delivered'
  };
  res.setHeader('Content-Type', 'application/json');
  res.setHeader('Access-Control-Allow-Origin', '*');