Error http get request with headers

import { Injectable } from '@angular/core';
import { Http, Headers, RequestOptions } from '@angular/http';
import 'rxjs/add/operator/map';

/*
  Generated class for the MET provider.

  See https://angular.io/docs/ts/latest/guide/dependency-injection.html
  for more info on providers and Angular 2 DI.
*/
@Injectable()
export class MET {

    data: any;


  constructor(public http: Http) {
    console.log('Hello MET Provider');
  }

  getWeather(){

    let headers = new Headers({
        'Authorization': 'METToken 78f7a7071b641701fedd15f800b63764200567a2',
        'Content-Type': 'application/json'
     });

    let options = new RequestOptions({ headers: headers });

    let URL: string = 'http://api.met.gov.my/v2/data?datasetid=FORECAST&datacategoryid=GENERAL&locationid=LOCATION:19&start_date=2017-03-22&end_date=2017-03-29';

     if (this.data) {
      // already loaded data
        console.log('already reload data');
        return Promise.resolve(this.data);
      }

      // don't have the data yet
      return new Promise(resolve => {
        this.http.get(URL, options)
          /*.map(res => res.json())*/
          .subscribe(data => {
            this.data = data;
            console.log(this.data);
            resolve(this.data);
          });
      });

  }

}