angular – 测试Http Service进行多次调用并返回observable而不映射响应

我有一个数据服务,它从服务器获取数据并生成多个请求,然后返回一个可观察数组.我想测试数据.

我尝试做的是在我发送的mockrespone数组中包含两个observables我不知道这是否是测试数据的正确方法.

但是测试失败了,尤其是异步测试块中的最后三个测试

重要提示：我想测试一下,当将charId设置为falsy并将comicsId设置为falsy时,调用方法,订阅它返回的observable,在你模拟了http后,你会得到一个包含两个预期响应的数组.如果charId是真实的,则与预期的4个响应相同.当comicsId真实时,6个预期的回应也是如此

//获取数据的服务

getChar(): Observable<any> {

    const Observables = [];
    Observables.push(this.http.get('https://gateway.marvel.com:443/v1/public/characters?apikey'));
    Observables.push(this.http.get('https://gateway.marvel.com:443/v1/public/comics?apikey'));

    if (this.charId) {
      Observables.push(this.http.get(`${this.urlChar}${this.charId}${this.apiKey}`));
      Observables.push(this.http.get(`${this.urlChar}${this.charId}/comics${this.apiKey}`));
    }
    if (this.comicsId) {
      Observables.push(this.http.get(`${this.urlCom}${this.comicsId}${this.apiKey}`));
      Observables.push(this.http.get(`${this.urlCom}${this.comicsId}/creators${this.apiKey}`));
    }
    console.log([Observable,Observable]);
    return Observable.forkJoin(Observables);
  }
}

//我的考试

import { async,ComponentFixture,TestBed,getTestBed,inject } from '@angular/core/testing';
import { MockBackend,MockConnection } from '@angular/http/testing';
import { DataService } from './data.service';
import {
  BaseRequestOptions,Http,XHRBackend,HttpModule,Response,ResponseOptions,RequestMethod
} from '@angular/http';
import { Observable } from 'rxjs/Observable';

describe('DataService',() => {
  let mockBackend: MockBackend;

   beforeEach(async(() => {
    TestBed.configureTestingModule({
      providers: [
        DataService,MockBackend,BaseRequestOptions,{
          provide: Http,deps: [MockBackend,BaseRequestOptions],useFactory:
          (backend: XHRBackend,defaultOptions: BaseRequestOptions) => {
            return new Http(backend,defaultOptions);
          }
        }
      ],imports: [
        HttpModule
      ]
    });
    mockBackend = getTestBed().get(MockBackend);
  }));


  it('should get ObservableArr',(done) => {
    let dataService: DataService;

    getTestBed().compileComponents().then(() => {
      mockBackend.connections.subscribe(
        (connection: MockConnection) => {
          connection.mockRespond(new Response(
            new ResponseOptions({
              body: [Observable,Observable]
            }
            )));
        });

      dataService = getTestBed().get(DataService);
      expect(DataService).toBeDefined();

      dataService.getChar().subscribe((obsArr: Observable<any>[]) => {
        expect(obsArr.length).toBeDefined();
        expect(obsArr.length).toEqual(2);
        expect(obsArr.length).not.toBe(1);
        done();
      });
    });
  });


  it('should check the service',inject([DataService],(service: DataService) => {
      expect(service).toBeTruthy();
    }));

  it('should get ObservableArray async',async(inject([DataService],(dataService: DataService) => {
      mockBackend.connections.subscribe(
        (connection: MockConnection) => {
          connection.mockRespond(new Response(
            new ResponseOptions({
              body: [Observable,Observable]
            }
            )));
        });
      dataService.getChar().subscribe(
        (response) => {
          expect(response.length).toBe(2);
          expect(response[0]).toBe(Observable); <<<<<<<<<<<<<< Fails
          expect(response[1]).toBe(Observable); <<<<<<<<<<<<<< Fails
          expect(response).toEqual([Observable,Observable]); <<<<<< Fails
        });
    })));
});

首先,正如@Aviad P.指出的那样,forkJoin方法不返回一个Observable的Observable数组……它返回一个forkJoin中每个observable结果的数组,并且该observable的结果不是Observables实例.

此外,你没有嘲笑getChart()方法,模拟后端你正在模拟每个http调用,但不是方法getChar()本身.数组必须是=== 2的长度,因为不存在this.chartId和this.comicsId ……

所以我会说返回的结构是这样的,所以response [0]是一个数组：

response = [[Observable,Observable],[Observable,Observable]]

说,这种期望永远不会成真,因为没有一个数组等于创建的新数组：

expect(response).toEqual([Observable,Observable])

修改所有应解决问题的方法.另外,如果你的Observables返回了Observable实例,你的代码：’body：[Observable,Observable]’没有返回Observables实例,它返回Observable定义函数,这将是一个不正确的mock,虽然测试会通过.

这将是一个失败的测试示例：

const mockResponse = {isMockResponse: true};

it('should get ObservableArray async',(dataService: DataService) => {
  mockBackend.connections.subscribe(
    (connection: MockConnection) => {
      connection.mockRespond(new Response(
        new ResponseOptions({
          body: {...mockResponse}
        }
        )));
    });
  dataService.getChar().subscribe(
    (response) => {
      expect(response.length).toBe(2);
      expect(response[0].isMockResponse).toBe(true); <<< Is this expect really necessary?
      expect(response[1].isMockResponse).toBe(true); <<< Is this expect really necessary?
    });
})));

说,唯一的期望是测试你的用例是这样的：

expect(response.length).toBe(2);

其他的是不必要的…所以你没有测试你正在嘲笑的数据,你想测试由于变量this.chartId和this.comicsIs的值而执行的调用次数.

希望这可以帮助.