Listen to user.deleted events to delete the corresponding user ads

src/app.constants.ts

@@ -20,6 +20,10 @@ export const MATCHER_AD_CREATION_FAILED_ROUTING_KEY =
   'matcher-ad.creation-failed';
 export const MATCHER_AD_CREATION_FAILED_QUEUE = 'ad.matcher-ad.creation-failed';
 
+export const USER_DELETED_MESSAGE_HANDLER = 'userDeleted';
+export const USER_DELETED_ROUTING_KEY = 'user.deleted';
+export const USER_DELETED_QUEUE = 'ad.user.deleted';
+
 // configuration
 export const SERVICE_CONFIGURATION_SET_QUEUE = 'ad-configuration-set';
 export const SERVICE_CONFIGURATION_DELETE_QUEUE = 'ad-configuration-delete';

src/modules/ad/ad.module.ts

@@ -12,6 +12,7 @@ import {
 import { AdMapper } from './ad.mapper';
 import { CreateAdService } from './core/application/commands/create-ad/create-ad.service';
 import { DeleteAdService } from './core/application/commands/delete-ad/delete-ad.service';
+import { DeleteUserAdsService } from './core/application/commands/delete-user-ads/delete-user-ads.service';
 import { InvalidateAdService } from './core/application/commands/invalidate-ad/invalidate-ad.service';
 import { ValidateAdService } from './core/application/commands/validate-ad/validate-ad.service';
 import { PublishMessageWhenAdIsDeletedDomainEventHandler } from './core/application/event-handlers/publish-message-when-ad-deleted.domain-event-handler';
@@ -32,6 +33,7 @@ import { FindAdsByIdsGrpcController } from './interface/grpc-controllers/find-ad
 import { FindAdsByUserIdGrpcController } from './interface/grpc-controllers/find-ads-by-user-id.grpc.controller';
 import { MatcherAdCreatedMessageHandler } from './interface/message-handlers/matcher-ad-created.message-handler';
 import { MatcherAdCreationFailedMessageHandler } from './interface/message-handlers/matcher-ad-creation-failed.message-handler';
+import { UserDeletedMessageHandler } from './interface/message-handlers/user-deleted.message-handler';
 
 const grpcControllers = [
   CreateAdGrpcController,
@@ -44,6 +46,7 @@ const grpcControllers = [
 const messageHandlers = [
   MatcherAdCreatedMessageHandler,
   MatcherAdCreationFailedMessageHandler,
+  UserDeletedMessageHandler,
 ];
 
 const eventHandlers: Provider[] = [
@@ -54,6 +57,7 @@ const eventHandlers: Provider[] = [
 const commandHandlers: Provider[] = [
   CreateAdService,
   DeleteAdService,
+  DeleteUserAdsService,
   ValidateAdService,
   InvalidateAdService,
 ];

src/modules/ad/core/application/commands/delete-user-ads/delete-user-ads.command.ts

@@ -0,0 +1,7 @@
+import { Command, CommandProps } from '@mobicoop/ddd-library';
+
+export class DeleteUserAdsCommand extends Command {
+  constructor(props: CommandProps<DeleteUserAdsCommand>) {
+    super(props);
+  }
+}

src/modules/ad/core/application/commands/delete-user-ads/delete-user-ads.service.ts

@@ -0,0 +1,29 @@
+import { AdEntity } from '@modules/ad/core/domain/ad.entity';
+import {
+  CommandBus,
+  CommandHandler,
+  ICommandHandler,
+  QueryBus,
+} from '@nestjs/cqrs';
+import { FindAdsByUserIdQuery } from '../../queries/find-ads-by-user-id/find-ads-by-user-id.query';
+import { DeleteAdCommand } from '../delete-ad/delete-ad.command';
+import { DeleteUserAdsCommand } from './delete-user-ads.command';
+
+@CommandHandler(DeleteUserAdsCommand)
+export class DeleteUserAdsService implements ICommandHandler {
+  constructor(
+    private readonly queryBus: QueryBus,
+    private readonly commandBus: CommandBus,
+  ) {}
+
+  async execute(command: DeleteUserAdsCommand): Promise<void> {
+    const ads: AdEntity[] = await this.queryBus.execute(
+      new FindAdsByUserIdQuery(command.id),
+    );
+    await Promise.all(
+      ads.map((ad) =>
+        this.commandBus.execute(new DeleteAdCommand({ id: ad.id })),
+      ),
+    );
+  }
+}

src/modules/ad/interface/message-handlers/user-deleted.message-handler.ts

@@ -0,0 +1,23 @@
+import { IntegrationEvent } from '@mobicoop/ddd-library';
+import { RabbitSubscribe } from '@mobicoop/message-broker-module';
+import { DeleteUserAdsCommand } from '@modules/ad/core/application/commands/delete-user-ads/delete-user-ads.command';
+import { Injectable } from '@nestjs/common';
+import { CommandBus } from '@nestjs/cqrs';
+import { USER_DELETED_MESSAGE_HANDLER } from '@src/app.constants';
+
+type UserDeletedEvent = IntegrationEvent;
+
+@Injectable()
+export class UserDeletedMessageHandler {
+  constructor(private readonly commandBus: CommandBus) {}
+
+  @RabbitSubscribe({
+    name: USER_DELETED_MESSAGE_HANDLER,
+  })
+  public async userDeleted(message: string) {
+    const deletedUser: UserDeletedEvent = JSON.parse(message);
+    await this.commandBus.execute(
+      new DeleteUserAdsCommand({ id: deletedUser.id }),
+    );
+  }
+}

src/modules/messager/messager.module.ts

@@ -1,6 +1,11 @@
 import { Module, Provider } from '@nestjs/common';
 import { MESSAGE_PUBLISHER } from './messager.di-tokens';
 
+import {
+  MessageBrokerModule,
+  MessageBrokerModuleOptions,
+  MessageBrokerPublisher,
+} from '@mobicoop/message-broker-module';
 import { ConfigModule, ConfigService } from '@nestjs/config';
 import {
   MATCHER_AD_CREATED_MESSAGE_HANDLER,
@@ -10,12 +15,10 @@ import {
   MATCHER_AD_CREATION_FAILED_QUEUE,
   MATCHER_AD_CREATION_FAILED_ROUTING_KEY,
   SERVICE_NAME,
+  USER_DELETED_MESSAGE_HANDLER,
+  USER_DELETED_QUEUE,
+  USER_DELETED_ROUTING_KEY,
 } from '@src/app.constants';
-import {
-  MessageBrokerModule,
-  MessageBrokerModuleOptions,
-  MessageBrokerPublisher,
-} from '@mobicoop/message-broker-module';
 
 const imports = [
   MessageBrokerModule.forRootAsync({
@@ -41,6 +44,10 @@ const imports = [
           routingKey: MATCHER_AD_CREATION_FAILED_ROUTING_KEY,
           queue: MATCHER_AD_CREATION_FAILED_QUEUE,
         },
+        [USER_DELETED_MESSAGE_HANDLER]: {
+          routingKey: USER_DELETED_ROUTING_KEY,
+          queue: USER_DELETED_QUEUE,
+        },
       },
     }),
   }),

tests/unit/ad/core/delete-user-ads.service.spec.ts

@@ -0,0 +1,53 @@
+import { DeleteUserAdsCommand } from '@modules/ad/core/application/commands/delete-user-ads/delete-user-ads.command';
+import { DeleteUserAdsService } from '@modules/ad/core/application/commands/delete-user-ads/delete-user-ads.service';
+import { AdEntity } from '@modules/ad/core/domain/ad.entity';
+import { CommandBus, QueryBus } from '@nestjs/cqrs';
+import { Test, TestingModule } from '@nestjs/testing';
+import { punctualPassengerCreateAdProps } from './ad.fixtures';
+
+const userAds = [
+  AdEntity.create(punctualPassengerCreateAdProps()),
+  AdEntity.create(punctualPassengerCreateAdProps()),
+];
+
+const mockQueryBus = {
+  execute: jest.fn().mockImplementation(() => userAds),
+};
+
+const mockCommandBus = {
+  execute: jest.fn(),
+};
+
+describe('delete-user-ads.service', () => {
+  let deleteUserAdsService: DeleteUserAdsService;
+
+  beforeAll(async () => {
+    const module: TestingModule = await Test.createTestingModule({
+      providers: [
+        {
+          provide: QueryBus,
+          useValue: mockQueryBus,
+        },
+        {
+          provide: CommandBus,
+          useValue: mockCommandBus,
+        },
+        DeleteUserAdsService,
+      ],
+    }).compile();
+
+    deleteUserAdsService =
+      module.get<DeleteUserAdsService>(DeleteUserAdsService);
+  });
+
+  it('should be defined', () => {
+    expect(deleteUserAdsService).toBeDefined();
+  });
+
+  it('should call the delete command for each ad returned by the query', async () => {
+    await deleteUserAdsService.execute(
+      new DeleteUserAdsCommand({ id: userAds[0].getProps().userId }),
+    );
+    expect(mockCommandBus.execute).toHaveBeenCalledTimes(userAds.length);
+  });
+});

tests/unit/ad/interface/user-deleted.message-handler.spec.ts

@@ -0,0 +1,43 @@
+import { UserDeletedMessageHandler } from '@modules/ad/interface/message-handlers/user-deleted.message-handler';
+import { CommandBus } from '@nestjs/cqrs';
+import { Test, TestingModule } from '@nestjs/testing';
+
+const mockCommandBus = {
+  execute: jest.fn(),
+};
+
+describe('Matcher Ad Created Message Handler', () => {
+  let userDeletedMessageHandler: UserDeletedMessageHandler;
+
+  beforeAll(async () => {
+    const module: TestingModule = await Test.createTestingModule({
+      providers: [
+        {
+          provide: CommandBus,
+          useValue: mockCommandBus,
+        },
+        UserDeletedMessageHandler,
+      ],
+    }).compile();
+
+    userDeletedMessageHandler = module.get<UserDeletedMessageHandler>(
+      UserDeletedMessageHandler,
+    );
+  });
+
+  afterEach(async () => {
+    jest.clearAllMocks();
+  });
+
+  it('should be defined', () => {
+    expect(userDeletedMessageHandler).toBeDefined();
+  });
+
+  it('should call the command bus', async () => {
+    const userId = '4eb6a6af-ecfd-41c3-9118-473a507014d4';
+    const userDeletedMessage = `{"id":"${userId}"}`;
+    await userDeletedMessageHandler.userDeleted(userDeletedMessage);
+    expect(mockCommandBus.execute).toHaveBeenCalledTimes(1);
+    expect(mockCommandBus.execute.mock.lastCall[0].id).toBe(userId);
+  });
+});