how to throw observable error in angular http interceptor

Question

I tried to throw an observable error in the interceptor and then handles this error. but I can\'t. When success is false, I can also receive successful subscribe.

I

Answer 1

You can add catch, and handle error

//....
import 'rxjs/add/operator/catch';
import 'rxjs/add/observable/throw';
import 'rxjs/add/operator/map';

@Injectable()
export class TokenInterceptor implements HttpInterceptor {
    constructor(private inj: Injector, private _router: Router) {
    }

    intercept(req: HttpRequest, next: HttpHandler): Observable> {
        // Get the auth header from the service.
        const auth = this.inj.get(AuthService);
        const authToken = auth.getSessionData().accessToken || '';
        const duplicate = req.clone({headers: req.headers.set('Authorization', authToken)});
        return next.handle(duplicate).catch(this.handleError);
    }

    private handleError = (response: any) => {
// ....
        // Do messaging and error handling here
        return Observable.throw(response);
    }