How to pass data from angular 6 to Nodejs?

Question

Im using angular 6 & I have never used angular before. I need to send data to nodejs server. Im using the following code in angular function

     import { Component, OnInit } from '@angular/core';
     import { HttpClient,HttpHeaders  } from '@angular/common/http';

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


     fun_add(Id, cat) {
     return this.http.post('/go', data, 
      httpOptions).subscribe(result => {
        console.log(result);
       }, error => console.log('There was an error: '));
      }

In my nodejs,

    app.post('/go', function (req, res) {
      console.log("hi");
      })

But I couldnt go to the server. Im getting the error msg 'there was an error'. can anyone please help me with this?

Answer 1

You never send a response (e.g. with res.send()), so the server gets the request and sits there.

Meanwhile, the client waits, and waits, and eventually times out and throws an error because the server never responded.

Answer 2

    let api_url = 'http:localhost:portNumber'

   fun_add(Id, cat) {
      return this.http.post(api_url+'/go', data, 
          httpOptions).subscribe(result => {
            console.log(result);
       }, error => console.log('There was an error: '));
    }

Answer 3

Add this code in component

constructor(private http: HttpClient);

It's Working.