JAVASCRIPT

res.json in express

res.status(200).json({ message: "Hello world" })

res.json({token});

res.status(500).json('Server Error');

return res.status(400).json({
  errors: errors.array()
});

express req get json

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

app.use(express.json());

app.post('*', (req, res) => {
  req.body;	// The json object sent to the server
});
const port = 3000;
app.listen(port, () => console.log(`Listening on port ${port}.`));