Angular 中的单元测试 http 上下文

Question

I have this API call in my service

import { HttpContext } from '@angular/common/http';
export const SET_INVALID_TOKEN = new HttpContextToken(() => false);
...
    postSomething() {
        this.httpClient.post<MyModel>(`${this.API_SERVER_ADDRESS}/...`, {...}, { context: new HttpContext().set(SET_INVALID_TOKEN, true) })
    }

The reason I am using this context is to debug invalid token cases to my interceptors. You can find more information about this on this article . I should mention here that this context is used ONLY for debugging purposes. The point is that it should never be forgotten at a production stage.

Here is my unit test for the api call

fit('should ...', (done: DoneFn) => {
    let httpTestingController = TestBed.get(HttpTestingController);
    let service = TestBed.get(AnalysisAPIService);
    service.postSomething().subscribe(
        analyses => {
            ...
            done()
        },
        done.fail
    )
    const req = httpTestingController.expectOne(service["API_SERVER_ADDRESS"] + "/...");
    console.log(req.request.context.keys())
    req.flush(AnalysisMock.mockAnalysesResponse)// allows to use the dummy data
    
});

PROBLEM

The req.request.context.keys() is an empty object

QUESTION

how can I check for my unit test if there is an HttpContext set?

Answer 1

Instead of relying on the http mock, you can use spies

const spy = jasmine.createSpy().and.returnValue(of(EMPTY));

service['httpClient'].post = spy;

service.postSomething();

expect(spy.calls.argsFor(1)[1].context instanceof HttpContext).toBeTrue();

Answer 2

You can provide a callback to HttpTestingController.expectOne and make assertions on the request in the callback function.

Either by returning true/false for if the request meets your conditions:

const req = httpController.expectOne((r) => {
  return r.context.get(SET_INVALID_TOKEN);
});
req.flush(mockResponse);

or using explicit expectations (not sure if this is recommended but I like this more):

const req = httpController.expectOne((r) => {
  expect(r.context.url).toEqual("https://localhost:3000/blah");
  expect(r.context.get(SET_INVALID_TOKEN).toBeFalse();
  expect(r.headers.get("my-header").toEqual("my-header-value");
  return true;
});
req.flush(mockResponse);