无法从socket.io获取数据/将数据发布到Angular客户端

Question

这里我有一个socket.io服务器，它从节点api和angular客户端获取数据。我用套接字客户端测试了套接字服务器，我可以获取数据。但是当我尝试获取数据时，我也无法获取，也无法发送帖子数据。

注意：我们每次执行请求时都会返回值

下面是我的套接字服务器代码

var socket = io.listen(server);
socket.on('connection', function (client) {
  // new client is here! 
  client.on('getreq', function () {
    http.get("http://localhost:3000/book", function (res) {
      let data = []
      res.on('data', chunk => {
        data.push(chunk)
      });
      res.on('end', () => {
        console.log(JSON.parse(data));
        client.send(JSON.parse(data));
      })

    });

  });


  client.on('posreq', function (postdata) {
    
    request.post('http://localhost:3000/book',{
      json: {
        postdata
      }},(error, res, body)=>{
        if (error) {
          console.error(error)
          return
        }
        console.log(`statusCode: ${res.statusCode}`)
        console.log(body)
        client.send(body)
      }
      
      
      )

  });

  client.on('disconnect', function () {
    console.log('connection closed');
  });

});

角度代码： service.ts

import * as io from 'socket.io-client';
import { Observable } from 'rxjs';
observable: Observable<any>;
  public socketUrl = "http://localhost:4000";
  socket;

  constructor() {
    this.socket = io(this.socketUrl);
  }

  getData():Observable<any>{
    return this.observable = new Observable((observer) =>
      this.socket.emit('getreq', (data) => observer.next(data))
    );

  }

组件代码：

title = 'web-client';
  constructor(public sock:SocketIoService){

  }

  ngOnInit() {
      this.sock.getData().subscribe(res => {
        console.log(res);
        console.log('got data')
      });
  }

我如何将这些方法包括在我的节点客户端中？

 var socket = require('socket.io-client')('http://localhost:4000');
    
    
    socket.connect();
    
    socket.emit("getreq");
    socket.emit("posreq",JSON.stringify({ "title": "max"}));
    
    
    socket.on('connect', function(){
        console.log('connected');
        socket.send('hi!'); 
    });
    
    
    socket.on('message', function(data){ 
        console.log('message recived: ' + JSON.stringify(data));
    });
    
    socket.on('disconnect', function(){
        console.log('disconected');
    });