基于vue-ssr服务端渲染入门详解(7)

const resolve = file => path.resolve(__dirname, file)
function createRenderer (bundle, options) {
 return createBundleRenderer(bundle, Object.assign(options, {
 template,
 cache: LRU({
  max: 1000,
  maxAge: 1000 * 60 * 15
 }),
 basedir: resolve('./dist'),
 runInNewContext: false
 }))
}
let renderer;
let readyPromise
if (isProd) {
 const bundle = require('./dist/vue-ssr-server-bundle.json')
 const clientManifest = require('./dist/vue-ssr-client-manifest.json')
 renderer = createRenderer(bundle, {
 clientManifest
 })
} else {
 readyPromise = require('./build/setup-dev-server')(server, (bundle, options) => {
 renderer = createRenderer(bundle, options)
 })
}

const server = express()；

//定义在启动服务钱先判断中间件中的缓存是否过期，是否直接调用dist文件。
const serve = (path, cache) => express.static(resolve(path), {
 maxAge: cache && isProd ? 1000 * 60 * 60 * 24 * 30 : 0
})
server.use('/dist', serve('./dist', true))
server.get('*', (req, res) => {
 const context = {
 title: 'hello',
 url: req.url
 }
 renderer.renderToString(context, (err, html) => {
 if (err) {
  res.status(500).end('Internal Server Error')
  return
 }
 res.end(html)
 })
})

function probe(port, callback) {
 let servers = net.createServer().listen(port)
 let calledOnce = false
 let timeoutRef = setTimeout(function() {
  calledOnce = true
  callback(false, port)
 }, 2000)
 timeoutRef.unref()
 let connected = false
 servers.on('listening', function() {
  clearTimeout(timeoutRef)

  if (servers)
   servers.close()

  if (!calledOnce) {
   calledOnce = true
   callback(true, port)
  }
 })
 servers.on('error', function(err) {
  clearTimeout(timeoutRef)

  let result = true
  if (err.code === 'EADDRINUSE')
   result = false

  if (!calledOnce) {
   calledOnce = true
   callback(result, port)
  }
 })
}
const checkPortPromise = new Promise((resolve) => {
 (function serverport(_port) {
  let pt = _port || 8080;
  probe(pt, function(bl, _pt) {
   // 端口被占用 bl 返回false
   // _pt：传入的端口号
   if (bl === true) {
    // console.log("\n Static file server running at" + "\n\n=> http://localhost:" + _pt + '\n');
    resolve(_pt);
   } else {
    serverport(_pt + 1)
   }
  })
 })()

})
checkPortPromise.then(data => {
 uri = 'http://localhost:' + data;
 console.log('启动服务路径'+uri)
 server.listen(data);
});