Angular 2, best practice to load data from a server one time and share results to components [duplicate]

Answer 1

Gunter is completely right regarding shared services!

Here are some more details for an HTTP that relies on observables and cached data for next calls:

export class SharedService {
  constructor(private http:Http) {
  }

  getData() {
    if (this.cachedData) {
      return Observable.of(this.cachedData);
    } else {
      return this.http.get(...)
            .map(res => res.json())
            .do((data) => {
              this.cachedData = data;
            });
    }
  }
}