react-garden/src/pages/api/cors.ts

React + TypeScript + ThreeJS app using Material UI on NextJS, Apollo Client, GraphQL + WordPress REST APIs, for ThreeD web development.. a part of the threed.ai code family.

import type { NextApiRequest, NextApiResponse } from 'next'
import Cors from 'cors'

// Initializing the cors middleware
// You can read more about the available options here: https://github.com/expressjs/cors#configuration-options
const cors = Cors({
  methods: ['POST', 'GET', 'HEAD'],
})

// Helper method to wait for a middleware to execute before continuing
// And to throw an error when an error happens in a middleware
function runMiddleware(
  req: NextApiRequest,
  res: NextApiResponse,
  fn: Function
) {
  return new Promise((resolve, reject) => {
    fn(req, res, (result: any) => {
      if (result instanceof Error) {
        return reject(result)
      }

      return resolve(result)
    })
  })
}

export default async function handler(
  req: NextApiRequest,
  res: NextApiResponse
) {
  // Run the middleware
  await runMiddleware(req, res, cors)

  // Rest of the API logic
  res.json({ message: 'Hello Everyone!' })
}