在 e2e 测试 NestJS 时使用测试数据库

Question

在这个项目中，它使用了 NestJS 和 TypeORM。对于真正的 API 请求，CRUD 操作是在 MySQL（使用 AWS RDS）上进行的。

现在我正在尝试使用 SQLite(In-Memory) 来测试 API 结果。

我在单元测试中成功实现了这个，如下代码。

首先，下面是create-memory-db.ts，它返回一个到内存中SQLite数据库的连接。

type Entity = Function | string | EntitySchema<any>;

export async function createMemoryDB(entities: Entity[]) {
  return createConnection({
    type: 'sqlite',
    database: ':memory:',
    entities,
    logging: false,
    synchronize: true,
  });
}

• 通过使用上面的导出函数，我成功运行了单元测试，如下所示。

describe('UserService Logic Test', () => {
  let userService: UserService;
  let connection: Connection;
  let userRepository: Repository<User>;

  beforeAll(async () => {
    connection = await createMemoryDB([User]);
    userRepository = await connection.getRepository(User);
    userService = new UserService(userRepository);
  });

  afterAll(async () => {
    await connection.close();
  });

  afterEach(async () => {
    await userRepository.query('DELETE FROM users');
  });

  // testing codes.
});

我正在尝试在 e2e 测试中做同样的事情。我试过下面的代码。

// user.e2e-spec.ts

describe('UserController (e2e)', () => {
  let userController: UserController;
  let userService: UserService;
  let userRepository: Repository<User>;
  let connection: Connection;
  let app: INestApplication;
  const NAME = 'NAME';
  const EMAIL = 'test@test.com';
  const PASSWORD = '12345asbcd';

  beforeAll(async () => {
    connection = await createMemoryDB([User]);
    userRepository = await connection.getRepository(User);
    userService = new UserService(userRepository);
    userController = new UserController(userService);

    const moduleFixture: TestingModule = await Test.createTestingModule({
      imports: [],
      controllers: [UserController],
      providers: [UserService],
    }).compile();

    app = moduleFixture.createNestApplication();
    await app.init();
  });

  afterAll(async () => {
    await connection.close();
  });

  afterEach(async () => {
    // await userRepository.query('DELETE FROM users');
  });

  it('[POST] /user : Response is OK if conditions are right', () => {
    const dto = new UserCreateDto();
    dto.name = NAME;
    dto.email = EMAIL;
    dto.password = PASSWORD;

    return request(app.getHttpServer())
      .post('/user')
      .send(JSON.stringify(dto))
      .expect(HttpStatus.CREATED);
  });
});

我无法创建UserModule，因为它没有带有Connection 参数的构造函数。 代码本身没有编译错误，但在执行e2e测试时得到如下结果。

Nest can't resolve dependencies of the UserService (?). Please make sure that the argument UserRepository at index[0] is available in the RootTestModule context.

Potential solutions:
- If UserRepository is a provider, is it part of the current RootTestModule?
- If UserRepository is exported from a seperate @Module, is that module imported within RootTestModule?
  @Module({
    imports: [/* The module containing UserRepository */]
  })


TypeError: Cannot read property 'getHttpServer' of undefined.

任何帮助将不胜感激。谢谢:)

---

• 更新：尝试以下操作后出现新错误。

describe('UserController (e2e)', () => {
  let userService: UserService;
  let userRepository: Repository<User>;
  let connection: Connection;
  let app: INestApplication;
  const NAME = 'NAME';
  const EMAIL = 'test@test.com';
  const PASSWORD = '12345asbcd';

  beforeAll(async () => {
    connection = await createMemoryDB([User]);
    userRepository = await connection.getRepository(User);
    userService = new UserService(userRepository);

    const moduleFixture: TestingModule = await Test.createTestingModule({
      imports: [UserModule],
    })
      .overrideProvider(UserService)
      .useClass(userService)
      .compile();

    app = moduleFixture.createNestApplication();
    await app.init();
  });

  afterAll(async () => {
    await connection.close();
  });

  afterEach(async () => {
    await userRepository.query('DELETE FROM users');
  });

  it('[POST] /user : Response is OK if conditions are right', async () => {
    const dto = new UserCreateDto();
    dto.name = NAME;
    dto.email = EMAIL;
    dto.password = PASSWORD;

    const result = await request(app.getHttpServer())
      .post('/user')
      .send(JSON.stringify(dto))
      .expect({ status: HttpStatus.CREATED });
  });
});

• 我检查了查询是否正常工作，并且能够看到它正在使用我想要的 SQLite 数据库。但是控制台出现了新的错误。

TypeError: metatype is not a constructor.

TypeError: Cannot read property 'getHttpServer' of undefined.

Answer 1

对于那些寻找命中端点并断言响应正文的设置 e2e 测试的人，您可以执行以下操作：

// app.module.ts
@Module({
  imports: [
    TypeOrmModule.forRootAsync({
      useFactory: async (configService: ConfigService) => {
        if (process.env.APPLICATION_ENV === 'test') {
          return {
            type: 'sqlite',
            database: ':memory:',
            entities: [Entity],
            synchronize: true,
          }
        }
        return {
          // your default options
        };
      },
    }),
  ]
})

Answer 2

好的，我通过在 Test.createTestingModule 的导入字段中使用 TypeOrm.forRoot() 解决了这个问题。以下是我的做法。

describe('UserController (e2e)', () => {
  let userService: UserService;
  let userRepository: Repository<User>;
  let app: INestApplication;
  const NAME = 'NAME';
  const EMAIL = 'test@test.com';
  const PASSWORD = '12345asbcd';

  beforeAll(async () => {
    const moduleFixture: TestingModule = await Test.createTestingModule({
      imports: [
        UserModule,
        TypeOrmModule.forRoot({
          type: 'sqlite',
          database: ':memory:',
          entities: [User],
          logging: true,
          synchronize: true,
        }),
      ],
    }).compile();

    app = moduleFixture.createNestApplication();
    await app.init();
    userRepository = moduleFixture.get('UserRepository');
    userService = new UserService(userRepository);
  });

  afterAll(async () => {
    await app.close();
  });

  afterEach(async () => {
    await userRepository.query('DELETE FROM users');
  });
});