server.js

const fs = require('fs');
const path = require('path');
const express = require('express');
const compression = require('compression');
const resolve = file => path.resolve(__dirname, file);
const { createBundleRenderer } = require('vue-server-renderer');

const isProd = false; //process.env.NODE_ENV == 'production';
const app = express();

function createRenderer(bundle, options) {
  return createBundleRenderer(bundle, options);
}

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('/dist', serve('./dist', true));
app.use('/public', serve('./public', true));
app.use('/manifest.json', serve('./manifest.json', true));

function render(req, res) {
  const s = Date.now();

  res.setHeader('Content-Type', 'text/html');
  res.setHeader('Server', 'TEST-VUE-SSR');

  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 = {
    title: 'Vue-SSR-Demo', // 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.get(
  '*',
  isProd
    ? render
    : (req, res) => {
        readyPromise.then(() => render(req, res));
      }
);

const port = process.env.PORT || 8082;
app.listen(port, () => {
  console.log(`server started at localhost:${port}`);
});