Use callback middleware functions as promises.

example.js

import promiseMiddleware from './promise_middleware'
import http from 'http'
import cors from 'cors'


http.createServer(async function (request, response) {
  const middleware = promiseMiddleware.bind(null, request, response)
  
  try {
    await middleware((request, response, next) => next())
    await middleware(cors())
  }
  catch (error) {
    response.statusCode = 500
    return response.end(`Oops, an error occured.`)
  }
  
  response.end(`Hello world!`)
}).listen(1337)

promise_middleware.js

/**
 * Use callback middleware functions as promises.
 * 
 * @param {Error} [error]
 * @param {Object} request
 * @param {Object} response
 * @param {Function} middleware
 */
export default function promiseMiddleware () {
  return new Promise((resolve, reject) =>

    // The last argument is the middleware function, let's invoke it.
    arguments[arguments.length - 1](

      // Exclude the last argument, invoke the middleware function with the
      // passed in arguments as positional arguments using the spread operator.
      ...Array.prototype.slice.call(arguments, 0, -1),

      // This is the `next` function expressed succinctly as an arrow function.
      // If it's called without an argument, it resolves the promise.
      error => error ? reject(error) : resolve()))
}