main.js

const fs = require('fs')
const path = require('path')
const LRU = require('lru-cache')
const express = require('express')
const favicon = require('serve-favicon')
const compression = require('compression')
const microcache = require('route-cache')
const resolve = file => path.resolve(__dirname, file)
const { createBundleRenderer } = require('vue-server-renderer')
const { getCityEntityByHostName, guid } = require('./server/tools')
const router = require('./routes')

const isProd = process.env.NODE_ENV === 'production'
const useMicroCache = process.env.MICRO_CACHE !== 'false'
const serverInfo =
  `express/${require('express/package.json').version} ` +
  `vue-server-renderer/${require('vue-server-renderer/package.json').version}`

const app = express()

const bodyParser = require('body-parser');
const cookieParser = require('cookie-parser');
const Mock = require('mockjs');

app.use(cookieParser('MAGICSTRING'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({
  extended: false
}));

app.use(function (req, res, next) {
  res.header("Access-Control-Allow-Origin", "*");
  res.header("Access-Control-Allow-Credentials", true);
  res.header("Access-Control-Allow-Methods", "POST, GET, PUT, DELETE, OPTIONS");
  res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept, X-Custom-Header");

  if ('OPTIONS' == req.method) {
    res.send(204);
  }
  else {
    next();
  }
});

function createRenderer(bundle, options) {
  // https://github.com/vuejs/vue/blob/dev/packages/vue-server-renderer/README.md#why-use-bundlerenderer
  return createBundleRenderer(bundle, Object.assign(options, {
    // for component caching
    cache: LRU({
      max: 1000,
      maxAge: 1000 * 60 * 15
    }),
    // this is only needed when vue-server-renderer is npm-linked
    basedir: resolve('./dist'),
    // recommended for performance
    runInNewContext: false
  }))
}

let renderer
let readyPromise
const templatePath = resolve('./src/index.template.html')
if (isProd) {
  // In production: create server renderer using template and built server bundle.
  // The server bundle is generated by vue-ssr-webpack-plugin.
  const template = fs.readFileSync(templatePath, 'utf-8')
  const bundle = require('./dist/vue-ssr-server-bundle.json')
  // The client manifests are optional, but it allows the renderer
  // to automatically infer preload/prefetch links and directly add <script>
  // tags for any async chunks used during render, avoiding waterfall requests.
  const clientManifest = require('./dist/vue-ssr-client-manifest.json')
  renderer = createRenderer(bundle, {
    template,
    clientManifest
  })
} else {
  // In development: setup the dev server with watch and hot-reload,
  // and create a new renderer on bundle / index template update.
  readyPromise = require('./build/setup-dev-server')(
    app,
    templatePath,
    (bundle, options) => {
      renderer = createRenderer(bundle, options)
    }
  )
}

const serve = (path, cache) => express.static(resolve(path), {
  maxAge: cache && isProd ? 1000 * 60 * 60 * 24 * 30 : 0
})

app.use(compression({ threshold: 0 }))
app.use(favicon('./public/logo-48.png'))
app.use('/dist', serve('./dist', true))
app.use('/public', serve('./public', true))
app.use('/manifest.json', serve('./manifest.json', true))
app.use('/service-worker.js', serve('./dist/service-worker.js'))

// since this app has no user-specific content, every page is micro-cacheable.
// if your app involves user-specific content, you need to implement custom
// logic to determine whether a request is cacheable based on its url and
// headers.
// 1-second microcache.
// https://www.nginx.com/blog/benefits-of-microcaching-nginx/
app.use(microcache.cacheSeconds(1, req => useMicroCache && req.originalUrl))

function render(req, res) {
  const s = Date.now();
  const city = getCityEntityByHostName(req.hostname);
  console.log('main.js > city , hostname:', city, req.hostname)
  res.setHeader("Content-Type", "text/html")
  res.setHeader("Server", serverInfo)

  const handleError = err => {
    if (err.url) {
      res.redirect(err.url)
    } else if (err.code === 404) {
      res.status(404).send('404 | Page Not Found')
    } else {
      // Render Error Page or Redirect
      res.status(500).send('500 | Internal Server Error')
      console.error(`error during render : ${req.url}`)
      console.error(err.stack)
    }
  }

  const context = {
    city,
    title: city ? city.label : '新闻系统', // default title
    url: req.url
  }
  renderer.renderToString(context, (err, html) => {
    if (err) {
      return handleError(err)
    }
    res.send(html)
    if (!isProd) {
      console.log(`whole request: ${Date.now() - s}ms`)
    }
  })
}


app.use('/api', router);


app.get('*', isProd ? render : (req, res, next) => {
  if (req.url.startsWith('/api')) {
    next();
    return;
  }
  readyPromise.then(() => render(req, res))
})


const port = process.env.PORT || 8080
app.listen(port, () => {
  console.log(`server started at localhost:${port}`)
})