如何测试有延迟的递归 http 请求？

Question

我的情况有点复杂，对于后端实现，我需要轮询后端直到

我从 BE
我从 BE
我继续进行的时间超过了我的重试次数（客户端 TO）

代码有效，针对后端的测试在所有三种情况下均成功。我也成功地测试了第一种和第二种情况，如果结果是瞬时的（模拟完成/立即失败的响应，中间没有得到 onGoing ）。但是，我无法测试第三种情况。每次尝试我都会遇到不同的错误，所以现在我转向 S.O 的集体思想。寻求帮助:-)

ts 文件：

doAction(content): Observable<resPassType> {
    return this.postAction(content) // private function that just calls HTTP Post at url1, and returns an actionId for polling
      .pipe(concatMap(action => this.poll(action))); // see below
}

private poll(action, retryCount = config.retryCount): Observable<resPassType>{
    return time(config.retryTime).pipe(switchMap(() =>
      this.getActionStatus(action) // private function that calls HTTP get at url2/action.id
      .pipe(concatMap ( res=> {
        retryCount--;
        if(retryCount < 0)
            return throwError('Action Timed Out'); // this is essentially what I want to test
        switch(res.action.state.toLowerCase()) {
            case 'completed':
                return of(resPassTypeData);//taken from within res.action. Successfully tested
            case 'failed':
                return throwError('Action Failed'); // successfully tested
            case 'ongoing':
                return this.poll(res.action, retryCount)
            default':
                return throwError('unexpeceted action state');
            }
        }))));
}

看到成功的测试可能会帮助你帮助我，所以这里包括失败的测试

it('should throw error if action failed`, fakeAsync(()=>{
    const mockGetActionResponse = {'action' : {'id' : mockActionId, state: 'Failed' }};
    
    service.doAction(mockContent).subscribe(
        () => {},
        err => expect(err).toEqual('Action Failed');
    );

    const postCall = httpTestingController.expectOne(url1);
    expect(postCall.request.method).toEqual('POST');
    expect(postCall.request.body).toEqual(mockContent);

    postCall.flush(mockPostActionResponse);

    tick(config.retryTime);

    const getCall = httpTestingController.expectOne(url2/mockActionId);
    expect(getCall .request.method).toEqual('Get');

    getCall.flush(mockGetActionResponse );
}));

这个测试有效。如何为案例 3 编写测试？编写相同的测试并将状态更改为 'onGoing' 并更改错误预期给我留下了错误

error expected no open requests found 1

我的直觉是这与递归或延迟或其他原因有关，因为这是 poll 被多次调用的唯一测试用例。任何线索将不胜感激:-)

编辑由于@Andrei 的评论和改进，代码已更新。问题仍然存在

Answer 1

@Andrei 在评论中找到的答案。

现在的工作代码如下所示：

it('should throw error if action timed out',()=>{
    const mockGetActionResponse = {'action' : {'id' : mockActionId, state: 'onGoing' }};

    service.doAction(mockContent).subscribe(
        () => {},
        err => expect(err).toEqual('Action Timed Out');
    );

    const postCall = httpTestingController.expectOne(url1);
    expect(postCall.request.method).toEqual('POST');
    expect(postCall.request.body).toEqual(mockContent);

    postCall.flush(mockPostActionResponse);

    for( let i=0; i<config.retryCount; i++) {
        tick(config.delayTime);
        const getCall = httpTestingController.expectOne(url2);
        expect(getCall.request.method).toEqual('GET');
        getCall.flush(mockGetActionResponse)
    }
})

如何测试有延迟的递归 http 请求？

How can I test recursive http requests that have a delay?

jasmine

karma-jasmine

angular

angular-httpclient