title: Property 'toPromise' does not exist on type 'Observable<Response>'
body: <pre class="lang-js prettyprint-override"><code>import { Headers, Http } from '@angular/http';
  
  @Injectable()
  export class PublisherService{
  
      private publishersUrl = 'app/publisher';
  
      constructor(private http: Http) { }
  
      getPublishers(): Promise&lt;Publisher[]&gt;{
          return this.http.get(this.publishersUrl)
                     .toPromise()
                     .then(response =&gt; response.json().data) 
                     .catch(this.handleError);
      }
  }    
  </code></pre>
  
  <p>I am getting this error:</p>
  
  <blockquote>
    <p>Property 'toPromise' does not exist on type 'Observable'.any</p>
  </blockquote>