錯誤：沒有HttpService的提供者！ 在Karma測試中

Question

我有一個角度2工具來監控服務器，剛開始測試。 當我嘗試模擬httpService時，我不知道如何模擬Rest-API，所以我在線查看，修復了一些錯誤，現在我已經陷入了這個錯誤。
這里錯誤：

Chrome 53.0.2785 (Windows 10 0.0.0) HttpServiceFront should use an HTTP call Servers FAILED
        Error: No provider for HttpServiceFront!
            at NoProviderError.Error (native)
            ...
            at drainMicroTaskQueue (webpack:///~/zone.js/dist/zone.js:368:0 <- config/karma-test-shim.js:6854:36)
Chrome 53.0.2785 (Windows 10 0.0.0): Executed 2 of 3 (1 FAILED) (skipped 1) (0.268 secs / 0.057 secs)

這是我的測試用例：

import {
    ResponseOptions,
    Response,
    Http,
    BaseRequestOptions,
    RequestMethod
} from '@angular/http';

import {
    TestBed, fakeAsync, inject
} from '@angular/core/testing';

import { HttpServiceFront } from '../app/services/httpServiceFront';

import { MockBackend, MockConnection } from '@angular/http/testing';

const mockHttpProvider = {
    deps: [ MockBackend, BaseRequestOptions ],
    useFactory: (backend: MockBackend, defaultOptions: BaseRequestOptions) => {
        return new Http(backend, defaultOptions);
    }
};

describe('HttpServiceFront', () => {
    beforeEach(() => {
        {Http, mockHttpProvider}
        TestBed.configureTestingModule(
            [MockBackend,
            BaseRequestOptions]
        )
    });

    it('should use an HTTP call Servers',
        inject(
            [HttpServiceFront, MockBackend],
            fakeAsync((service: HttpServiceFront, backend: MockBackend) => {
                backend.connections.subscribe((connection: MockConnection) => {

                    expect(connection.request.method).toBe(RequestMethod.Get);
                    expect(connection.request.url).toBe(
                        'http://localhost:8080/server');
                });

                service.getServers();
            })));
});

謝謝您的幫助 ：）

Answer 1

您的語法接縫錯誤，請檢查文檔 。 這樣的事情應該有效：

beforeEach(() => {
    TestBed.configureTestingModule({
        providers: [
          { provide: Http, useValue: mockHttpProvider },
          MockBackend,
          BaseRequestOptions]
    })
});