How to use/import http module?

import {bootstrap} from '@angular2/platform-browser-dynamic';
import {Component, enableProdMode, Injectable, OnInit} from '@angular/core';
import {Http, Headers, HTTP_PROVIDERS, URLSearchParams} from '@angular/http';
import 'rxjs/add/operator/map';

const API_KEY = '6c759d320ea37acf99ec363f678f73c0:14:74192489';

@Injectable()
class ArticleApi {
  constructor(private http: Http) {}
  
  seachArticle(query) {
    const endpoint="http://api.nytimes.com/svc/search/v2/articlesearch.json";
    const searchParams = new URLSearchParams()
    searchParams.set('api-key', API_KEY);
    searchParams.set('q', query);
    
    return this.http
      .get(endpoint, {search: searchParams})
      .map(res => res.json().response.docs);
  }
  
  postExample(someData) {
    const endpoint="https://your-endpoint";
    const headers = new Headers({'Content-Type': 'application/json'});
    
    return this.http
      .post(endpoint, JSON.stringify(someData), { headers: headers })
      .map(res => res.json());
  }
}

@Component({
  selector: 'app',
  template: `<ul>
                <li *ngFor="let article of articles | async"> {{article.headline.main}} </li>
             </ul>`, 
  providers: [HTTP_PROVIDERS, ArticleApi],
})
class App implements OnInit {
  constructor(private articleApi: ArticleApi) { }
  
  ngOnInit() {
    this.articles = this.articleApi.seachArticle('obama');
  }
}

enableProdMode();
bootstrap(App)
  .catch(err => console.error(err));