express post request body shows up as empty

server code

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

app.use(express.json());
app.use(express.urlencoded({ extended:true }));

app.post('/',(req,res)=>{
    console.log(req.body)
})

client code

const data = {idk:'stuff',idk2:'otherstuff'};

fetch('http://localhost:4000', {
    method:'POST',
    headers:{'Content-Type': 'application/json'},
    mode:'no-cors',
    body: JSON.stringify(data)
})

terminal shows: {} tried pretty much everything so help would be very much appreciated thanks in advance:)

Answer

You said mode: 'no-cors' which tells fetch to silently ignore anything which requires CORS permission.

Setting the Content-Type to application/json requires CORS permission so your request is sent with Content-Type: text/plain instead.

This doesn’t trigger the JSON body parser.

• Don’t use mode: 'no-cors'.
• Do configure your server to give permission using CORS