medium_p1_c2

server.js

//...

// CORS middleware
app.use(function (req, res, next) {
  // Allow Origins
  res.header("Access-Control-Allow-Origin", "*");
  // Allow Methods
  res.header("Access-Control-Allow-Methods", "GET, POST, PATCH, PUT, DELETE, OPTIONS");
  // Allow Headers
  res.header("Access-Control-Allow-Headers", "Origin, Accept, Content-Type, Authorization");
  // Handle preflight, it must return 200
  if (req.method === "OPTIONS") {
    // Stop the middleware chain
    return res.status(200).end();
  }
  // Next middleware 
  next();
});

//...