based on the example from Jonathan Serra using ngx-resource as of "^3.2.4"

rest-client-crud.resource.ts

// based on http://blog.slals.net/programming/2017/01/12/angular2-a-rest-client-interface.html
import { Http, Request } from '@angular/http';

import { ResourceCRUD, ResourceActionBase } from 'ngx-resource';

import { Observable } from 'rxjs/Observable';
import { Subscriber } from 'rxjs/Subscriber';

export class RestClientCRUD<TQuery, TShort, TFull> extends ResourceCRUD<TQuery, TShort, TFull> {
  $getHeaders(methodOptions?: any): any {
    const headers: any = {};
    if (methodOptions.auth) {
      headers.Authorization = localStorage.get('token');
    }
    return headers;
  }

  $responseInterceptor(observable: Observable<any>, request: Request, methodOptions?: any): Observable<any> {
    return Observable.create((subscriber: Subscriber<any>) => {
      observable.subscribe(
        (res: Response) => {
          if (res.headers) {
            const newToken: string = res.headers.get('Authorization');
            if (newToken) {
              localStorage.setItem('token', newToken);
            }
          }
          const body = (<any>res)._body;
          subscriber.next(body ? res.json() : null);
        },
        (error: Response) => {
          // I also made a layer to parse errors
          subscriber.error(new Error(error.statusText));
        },
        () => subscriber.complete()
      );

    });
  }
}