you-dont-need-cors-middleware-2019.md

You don't need CORS Middleware 2019

A node example using Zeit's Micro.

const micro = require('micro')

const server = micro(async (request, response) => {
  // set response headers
  response.setHeader('Access-Control-Allow-Headers', 'Access-Control-Allow-Origin')
  response.setHeader('Access-Control-Allow-Methods', 'POST,OPTIONS')
  response.setHeader('Access-Control-Allow-Origin', '*')

  // handle preflighted requests
  if (request.method === 'OPTIONS') {
    micro.send(response, 200, 'ok')
  }

  // your app goes here...
}

// start the server
server.listen(8080, () => {
  console.log('Listening on port 8080')
})

References

1. Zeit's Micro (github.com)
2. Node's setHeader Method (nodejs.org)
3. HTTP Response Headers (developer.mozilla.org)
4. Preflighted Requests (developer.mozilla.org)