NodeJs unable catch the data post from ReactJs form - node.js

Question

I using ReactJs build the form for user key in the details. I also using NodeJs to handle the post data from the React. But the NodeJs seem like did not catched the data.
This is react event handling
handleSave(e){
let caseData=this.state.caseInfo
let url = 'http://localhost:8080'
console.log(caseData)
fetch(url,{
method:"POST",
headers: {
'Accept': 'application/json',
'Content-Type': 'application/json'
},
data: JSON.stringify({caseInfo: caseData}),
})
}
This is NodeJS
var http = require('http');
var url = require('url');
var bodyParser = require('body-parser')
var express = require('express')
var app = express()
http.createServer(function(req,res){
app.use(bodyParser.urlencoded({extended:false}))
app.use(bodyParser.json())
app.use(function (req, res){
res.setHeader('Content-Type', 'text/plain')
res.write('you posted:\n')
res.end(JSON.stringify(req.body, null, 2))
console.log(JSON.stringify(req.body));
})
}).listen(8080);
I expect the data from the React can using post method to the Node and display the data in console log. However in the console of the server it display nothing.

Answer 1

It seems like you're not using express in the standard way. I'd change it to be more like the following...
app.use(bodyParser.json());
app.post('/', (req, res) => {
res.json({ posted: req.body });
console.log(JSON.stringify(req.body));
});
app.listen(8080);
And probably just get rid of the call to http.createServer altogether.
--
Check out the docs for more routing examples: https://expressjs.com/en/starter/basic-routing.html

Answer 2

If you are serving your react app from another server, for instance localhost:3000 (as used by create react app), and you are trying to make api calls to a server on localhost:8080 you are going to get CORS errors because the browser sees these as two different domains. To get started, you can look at the docs here: https://expressjs.com/en/resources/middleware/cors.html
But you will probably have to npm install cors where your server lives and use something like the following:
var express = require('express')
var cors = require('cors')
var app = express()
app.use(cors())
app.use(bodyParser.json());
app.post('/', (req, res) => {
res.json({ posted: req.body });
console.log(JSON.stringify(req.body));
});
app.listen(8080);