NestJS - Mongoose @InjectConnection單元測試

Question

我有一個在它的構造函數中使用@InjectConnection裝飾器的服務。

我無法為此服務實例化testingModule。 拋出以下錯誤： Nest can't resolve dependencies of the AttachmentsService (?, winston). Please make sure that the argument at index [0] is available in the TestModule context. Nest can't resolve dependencies of the AttachmentsService (?, winston). Please make sure that the argument at index [0] is available in the TestModule context.

服務構造函數：

  constructor(@InjectConnection() private readonly mongooseConnection: Mongoose,
              @Inject(Modules.Logger) private readonly logger: Logger) {
    this.attachmentGridFsRepository = gridfs({
      collection: 'attachments',
      model: Schemas.Attachment,
      mongooseConnection: this.mongooseConnection,
    });

    this.attachmentRepository = this.attachmentGridFsRepository.model;
  }

測試模塊構造函數：

const module: TestingModule = await Test.createTestingModule({
  imports: [
    WinstonModule.forRoot({
      transports: [
        new transports.Console({
          level: 'info',
          handleExceptions: false,
          format: format.combine(format.json()),
        }),
      ],
    }),
  ],
  providers: [AttachmentsService, {
    provide: getConnectionToken(''),
    useValue: {},
  }],
}).compile();

service = module.get<AttachmentsService>(AttachmentsService);

我意識到我必須模擬連接對象才能被GridFS調用，但是現在我無法實際構建測試模塊。

Answer 1

如果不添加顯式連接名稱，nest.js將使用默認連接標記 DatabaseConnection ，它由nestjs-mongoose包定義為常量：

export const DEFAULT_DB_CONNECTION = 'DatabaseConnection';

所以你可以使用getConnectionToken('Database') ：

providers: [AttachmentsService, {
  provide: getConnectionToken('Database'),
  useValue: {},
}]

---

更新2019年

拉取請求已合並。 你現在可以getConnectionToken() 。

我創建了一個pull請求 ，它允許不帶任何參數的getConnectionToken()返回默認連接令牌。