Angular Web Framework HTTP Client & API Integration 3

Question 1

What is the role of HttpParams in Angular HTTP requests?

Accepted Answer

Building an immutable, encodable set of URL query string parameters

Answer

HttpParams provides an immutable fluent API to construct, set, append, and percent-encode query string parameters for HTTP requests.

Question 2

How do you make an HTTP request that bypasses all registered HttpInterceptors?

Accepted Answer

Inject HttpBackend directly and use it to dispatch the request

Answer

HttpBackend sits behind the interceptor chain; injecting and using it directly dispatches requests without passing through any interceptors.

Question 3

Which RxJS operator should be used to cancel a pending HTTP request when a new trigger value arrives, preventing stale responses?

Accepted Answer

switchMap

Answer

switchMap unsubscribes from the previous inner observable (aborting the in-flight request) and subscribes to the new one, discarding stale responses.

Question 4

Which combination of HttpClient options is required to receive HTTP upload progress events?

Accepted Answer

reportProgress: true combined with observe: 'events', then filter for UploadProgress

Answer

reportProgress: true enables progress tracking while observe: 'events' surfaces the event stream; you then filter for HttpEventType.UploadProgress events.

Question 5

What must an HttpInterceptor call to forward the request to the next interceptor or to the actual HTTP backend?

Accepted Answer

next.handle(req)

Answer

next.handle(req) passes the (potentially modified) HttpRequest to the next interceptor in the chain, or directly to the backend if none remain.

Angular Web Framework Practice Test

Angular Web Framework Practice Test

Angular Web Framework HTTP Client & API Integration 3