how do you add a cors header in node js code example

Example 1: access-control-allow-origin nodejs express

// Add headers
app.use(function (req, res, next) {

    // Website you wish to allow to connect
    res.setHeader('Access-Control-Allow-Origin', 'http://localhost:8888');

    // Request methods you wish to allow
    res.setHeader('Access-Control-Allow-Methods', 'GET, POST, OPTIONS, PUT, PATCH, DELETE');

    // Request headers you wish to allow
    res.setHeader('Access-Control-Allow-Headers', 'X-Requested-With,content-type');

    // Set to true if you need the website to include cookies in the requests sent
    // to the API (e.g. in case you use sessions)
    res.setHeader('Access-Control-Allow-Credentials', true);

    // Pass to next layer of middleware
    next();
});

Example 2: cors package install npm

var express = require('express')var cors = require('cors')var app = express() app.get('/products/:id', cors(), function (req, res, next) {  res.json({msg: 'This is CORS-enabled for a Single Route'})}) app.listen(80, function () {  console.log('CORS-enabled web server listening on port 80')})