src/app/services/rest/core.service.ts

/// <reference path="../../../../typings/index.d.ts"/>

// Imports
import {AppConfig} from '../../config/app.config';
import { Injectable }     from '@angular/core';
import { Http, Response, Headers, RequestOptions } from '@angular/http';
import {Observable} from 'rxjs/Rx';

// Import RxJs required methods
import 'rxjs/add/operator/map';
import 'rxjs/add/operator/catch';

@Injectable()
export class CoreService {
  // Resolve HTTP using the constructor
  constructor (private http: Http) {}
  // private instance variable to hold base url
  private baseUrl = AppConfig.apiEndpoint;

  // Fetch all existing comments
  getCoreEndpoints() : Observable<any[]> {

    // ...using get request
    return this.http.get(`${this.baseUrl}/core/`)
    // ...and calling .json() on the response to return data
      .map((res:Response) => res.json())
      //...errors if any
      .catch((error:any) => Observable.throw(error.json().error || 'Server error'));

  }
}