myService.ts

/**
 * Created by benevideschissanga on 5/9/16.
 */
import {Injectable} from '@angular/core';
import {Http, Response} from '@angular/http';
import {Observable} from 'rxjs/Observable';
@Injectable()
export class MyService {
  private _videoUrl = 'api/videos.json';
  private _feedProductsUrl = 'api/images.json';
  private videoObservable = null;
  private productsObservable = null;

  constructor(private _http:Http) {

  }
  getFiles():any {
    //noinspection TypeScriptUnresolvedFunction
    if (this.productsObservable === null) {
      this.productsObservable = this._http.get(this._feedProductsUrl)
        .cache()
        //.delay(2000)
        .map(res => res.json())
        .catch(this.handleError);
    }
    return this.productsObservable;
  }

  getVideo() {
    // If we have account cached, use it instead
    if (this.videoObservable === null) {
      this.videoObservable = this._http.get(this._videoUrl)
        .share()
        .map(res => res.json())
        .catch(this.handleError);
    }
    return this.videoObservable;
  }

  private handleError = (error:Response)=> {
    console.error(error);
    return Observable.throw(error.json().error || 'Server error');
  }
}