How to handle errors from the server?

Question

JavaScript

I am learning angular, writing applications that could communicate with the server. Authentication occurs through a JWT token. For example, the situation is now, I send a request to the server to check the validity of the token. In response, I receive an answer, from which I pulled out an error somehow. But at the end, when throwing and returning an observable, the error additionally falls out. Obviously, I'm not handling the error correctly. Tell me the guru of angular and javascript.
authService

export class AuthService {
  backendUrl = "http://127.0.0.1:8000/";
  constructor(private http: Http,
              private router: Router) { }

  verifyToken(token: string): Observable<{}>{
    let urlVerify = 'api-token-verify'
    let headers = new Headers({'Content-Type':'application/json'});
    let options = new RequestOptions({headers: headers});
    return this.http.post(this.backendUrl+'api-token-verify/', {token}, options)
      .map((response: Response) => response.json())
      .catch((error: Response) => this.handleError(error));
  }

  authLogin(login: string, password: string){
    let urlLogin = 'api/v1/auth/login';
    let headers = new Headers({'Content-Type':'application/json'});
    let options = new RequestOptions({headers: headers});
    return this.http.post(this.backendUrl+urlLogin, {username: login, password: password}, options)
      .map((response: Response) => response.json())
      .catch(this.handleError);
  }

  handleError(error: any){
    this.router.navigate(['/login']);
    let err_array = error.json()
    return Observable.throw(err_array['non_field_errors']);
  }
}

authenticationGuard

export class AuthenticationGuard implements CanActivate {

  constructor(private authService: AuthService,
              private router: Router){
  }

  canActivate(
    next: ActivatedRouteSnapshot,
    state: RouterStateSnapshot): Observable<boolean> | Promise<boolean> | boolean {
      if(localStorage.getItem('Token')){
        let token = localStorage.getItem('Token');
        return this.authService.verifyToken(token).map(res => {
          if(res['token'] === token){
            return true;
          }
          console.log(res);
          return false;
        });
      }else{
        this.router.navigate(['/login']);
        return false;
      }
    }
}

Answer 1

You are not confused by two calls this.router.navigate(['/login']);in two places?
Why are you catching errors in the authorization service? If the router itself should monitor this, let it monitor it. Put interception and error handling there, and remove it from the service.