var express = require('express');
var app = express();

app.get('/hello', function (req, res) {
  res.send('Hello World!');
});

app.listen(3000, function () {
  console.log('Example app listening on port 3000!');
});

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

const httpOptions = {
    headers: new HttpHeaders({ 'Content-Type': 'application/json' })
};

@Injectable()
export class DemoService {

    constructor(private http:HttpClient) {}

    // Uses http.get() to load data from a single API endpoint
    getHello() {
        return this.http.get('/ello');
    }
}

import { DemoService } from './demo.service';

meassage: string;

ngOnInit() {
    this.message = this.getHello();
}

<h1>Message from Server</h1>
<p>{{message}}</p>