server.js

// Copyright 2019 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

const { createServer } = require('http')
const { join } = require('path')
const { parse } = require('url')
const next = require('next')

const port = process.env.PORT || 3000
const app = next({ dev: process.env.NODE_ENV !== 'production' })
const handle = app.getRequestHandler()

app.prepare()
  .then(() => {
    createServer((req, res) => {
      const parsedUrl = parse(req.url, true)
      const { pathname } = parsedUrl

      // handle GET request to /service-worker.js
      if (pathname === '/service-worker.js') {
        const filePath = join(__dirname, '.next', pathname)

        app.serveStatic(req, res, filePath)
      } else {
        handle(req, res, parsedUrl)
      }
    })
    .listen(port, () => {
      console.log(`> Ready on http://localhost:${3000}`)
    })
  })