将数据发送到节点中的服务器

Question

I am sending data to to server with AJAX using

function post(url) {
  return new Promise(function(resolve, reject) {
    var req = new XMLHttpRequest();
    req.open('POST', url);
    req.onload = function() {
      if (req.status == 200) {
        resolve(req.response);
      }
      else {
        reject(Error(req.statusText));
      }
    };
    req.onerror = function() {
      reject(Error("Network Error"));
    };
    var data = moldData();
    alert(JSON.stringify(data , null , 2 ))
    req.send( data );
  });
}

send.addEventListener('click', function(){
    post('http://localhost:8080/order').then(function(){
        alert('send')
    }).catch(function(e){
        alert(e)
    })
} 

on server side i am using

app.post('/order', function( req , res ){
  console.log('sup')
  console.log("=================\n" , req.body)
})

But whenever i post it , the promise does not get resolved nor rejected eg then nor catch gets executed. And on server side it just prints

"===============" "[Object object]"

I am using body parser eg

app.use(bodyParser.json())
app.use(bodyParser.urlencoded({extended: true}));
app.use(bodyParser.raw())
app.use(bodyParser.text())

I am fairly new to the backend development, why is this happening? What causes this? using

console.log(JSON.stingify(req.body,null,2))

results in the same output.

Thanks for help!

// Although the one part of question got answered. The main question was why req.body isnt printed , but instead , [Object object] is printed.

Answer 1

Your server side code logs two things and then stops.

The browser waits for a while and should eventually time out and reject the promise.

You have to send a response!

Look at the hello world example :

 res.send('Hello World!');

Answer 2

You need to stringify the server response when logging it.

console.log("=================\n" , JSON.stringify(req.body))

If you want to "pretty-print" the output, you can do this:

console.log("=================\n" , JSON.stringify(req.body, null, 4))