如何使从web api获取数据成为Angular 6

import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';
import { Observable } from 'rxjs';

@Injectable({
  providedIn: 'root'
})
export class DataService {

  private apiUrl = 'https://api.example.com/data';

  constructor(private http: HttpClient) { }

  getData(): Observable<any> {
    return this.http.get(this.apiUrl);
  }
}

import { Component, OnInit } from '@angular/core';
import { DataService } from './data.service';

@Component({
  selector: 'app-data-display',
  template: `<div>{{ data | json }}</div>`
})
export class DataDisplayComponent implements OnInit {
  data: any;

  constructor(private dataService: DataService) { }

  ngOnInit() {
    this.dataService.getData().subscribe(
      response => this.data = response,
      error => console.error('There was an error!', error)
    );
  }
}

{
  "/api": {
    "target": "https://api.example.com",
    "secure": false,
    "changeOrigin": true,
    "pathRewrite": {
      "^/api": ""
    }
  }
}

"architect": {
  "serve": {
    "options": {
      "proxyConfig": "src/proxy.conf.json"
    }
  }
}