使用 Fastify 对 NestJS 进行端到端测试：“@nestjs/platform-express”包丢失”错误答案

【问题标题】：End-to-end testing NestJS with Fastify: "@nestjs/platform-express" package is missing" error使用 Fastify 对 NestJS 进行端到端测试：“@nestjs/platform-express”包丢失”错误
【发布时间】：2021-12-30 14:43:00
【问题描述】：

我有一个使用 Fastify 的新 NestJS 应用程序。尝试npm run test:e2e 时出现以下错误：

[Nest] 14894   - 11/19/2021, 10:29:10 PM   [ExceptionHandler] The "@nestjs/platform-express" package is missing. Please, make sure to install this library ($ npm install @nestjs/platform-express) to take advantage of NestFactory.
  ●  process.exit called with "1"

      12 |     }).compile();
      13 | 
    > 14 |     app = moduleFixture.createNestApplication();
         |                         ^
      15 |     await app.init();
      16 |   });
      17 | 

      at Object.loadPackage (../node_modules/@nestjs/common/utils/load-package.util.js:13:17)
      at TestingModule.createHttpAdapter (../node_modules/@nestjs/testing/testing-module.js:25:56)
      at TestingModule.createNestApplication (../node_modules/@nestjs/testing/testing-module.js:13:43)
      at Object.<anonymous> (app.e2e-spec.ts:14:25)

 RUNS  test/app.e2e-spec.ts

Process finished with exit code 1

看起来很奇怪，为什么基于 fastify 的应用需要 platform-express？

【问题讨论】：

docs.nestjs.com/fundamentals/testing#end-to-end-testing

标签： node.js typescript nestjs fastify nestjs-fastify

【解决方案1】：

看来切换到 Fastify 后我们还需要相应地更新test/app.e2e-spec.ts：

import { Test, TestingModule } from '@nestjs/testing';
import * as request from 'supertest';
import { AppModule } from '../src/app.module';
import { FastifyAdapter, NestFastifyApplication } from '@nestjs/platform-fastify';

describe('AppController (e2e)', () => {
  let app: NestFastifyApplication;

  beforeEach(async () => {
    const moduleFixture: TestingModule = await Test.createTestingModule({
      imports: [AppModule],
    }).compile();

    app = moduleFixture.createNestApplication<NestFastifyApplication>(new FastifyAdapter());
    await app.init();
    await app.getHttpAdapter().getInstance().ready();
  });

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

  it('/ (GET)', () => {
    return request(app.getHttpServer()).get('/').expect(200).expect('Hello World!');
  });
});

【讨论】：