Move out start method from server (#5315)

- This makes sure the Next.js renderer / server doesn't have a dependency on the `http` module.
- Splits out util functions for SSR only
- Removes obsolete methods / methods that weren't being tree-shaken

bin/next-build

@@ -3,7 +3,7 @@ import { resolve, join } from 'path'
 import { existsSync } from 'fs'
 import parseArgs from 'minimist'
 import build from '../build'
-import { printAndExit } from '../lib/utils'
+import { printAndExit } from '../server/lib/utils'
 
 const argv = parseArgs(process.argv.slice(2), {
   alias: {

bin/next-dev

@@ -2,8 +2,8 @@
 import { resolve, join } from 'path'
 import parseArgs from 'minimist'
 import { existsSync } from 'fs'
-import Server from '../server'
-import { printAndExit } from '../lib/utils'
+import startServer from '../server/lib/start-server'
+import { printAndExit } from '../server/lib/utils'
 
 const argv = parseArgs(process.argv.slice(2), {
   alias: {
@@ -52,12 +52,9 @@ if (!existsSync(join(dir, 'pages'))) {
   printAndExit('> Couldn\'t find a `pages` directory. Please create one under the project root')
 }
 
-const srv = new Server({ dir, dev: true })
-srv.start(argv.port, argv.hostname)
+startServer({dir, dev: true}, argv.port, argv.hostname)
   .then(async () => {
-    if (!process.env.NOW) {
-      console.log(`> Ready on http://${argv.hostname ? argv.hostname : 'localhost'}:${argv.port}`)
-    }
+    console.log(`> Ready on http://${argv.hostname ? argv.hostname : 'localhost'}:${argv.port}`)
   })
   .catch((err) => {
     if (err.code === 'EADDRINUSE') {

bin/next-export

@@ -3,7 +3,7 @@ import { resolve, join } from 'path'
 import { existsSync } from 'fs'
 import parseArgs from 'minimist'
 import exportApp from '../export'
-import { printAndExit } from '../lib/utils'
+import { printAndExit } from '../server/lib/utils'
 
 const argv = parseArgs(process.argv.slice(2), {
   alias: {

bin/next-start

@@ -2,7 +2,7 @@
 
 import { resolve } from 'path'
 import parseArgs from 'minimist'
-import Server from '../server'
+import startServer from '../server/lib/start-server'
 
 const argv = parseArgs(process.argv.slice(2), {
   alias: {
@@ -44,12 +44,9 @@ if (argv.help) {
 
 const dir = resolve(argv._[0] || '.')
 
-const srv = new Server({ dir })
-srv.start(argv.port, argv.hostname)
+startServer({dir}, argv.port, argv.hostname)
   .then(() => {
-    if (!process.env.NOW) {
-      console.log(`> Ready on http://${argv.hostname ? argv.hostname : 'localhost'}:${argv.port}`)
-    }
+    console.log(`> Ready on http://${argv.hostname ? argv.hostname : 'localhost'}:${argv.port}`)
   })
   .catch((err) => {
     console.error(err)

lib/app.js

@@ -1,7 +1,7 @@
 import React, { Component } from 'react'
 import PropTypes from 'prop-types'
 import shallowEquals from './shallow-equals'
-import { execOnce, warn, loadGetInitialProps } from './utils'
+import { execOnce, loadGetInitialProps } from './utils'
 import { makePublicRouterInstance } from './router'
 
 export default class App extends Component {
@@ -79,7 +79,7 @@ export class Container extends Component {
 
 const warnUrl = execOnce(() => {
   if (process.env.NODE_ENV !== 'production') {
-    warn(`Warning: the 'url' property is deprecated. https://err.sh/zeit/next.js/url-deprecated`)
+    console.error(`Warning: the 'url' property is deprecated. https://err.sh/zeit/next.js/url-deprecated`)
   }
 })
 

lib/link.js

@@ -4,7 +4,7 @@ import { resolve, format, parse } from 'url'
 import React, { Component, Children } from 'react'
 import PropTypes from 'prop-types'
 import Router, { _rewriteUrlForNextExport } from './router'
-import { warn, execOnce, getLocationOrigin } from './utils'
+import { execOnce, getLocationOrigin } from './utils'
 
 function isLocal (href) {
   const url = parse(href, false, true)
@@ -14,8 +14,6 @@ function isLocal (href) {
     (url.protocol === origin.protocol && url.host === origin.host)
 }
 
-const warnLink = execOnce(warn)
-
 function memoizedFormatUrl (formatUrl) {
   let lastHref = null
   let lastAs = null
@@ -155,6 +153,8 @@ class Link extends Component {
 }
 
 if (process.env.NODE_ENV === 'development') {
+  const warn = execOnce(console.error)
+
   // This module gets removed by webpack.IgnorePlugin
   const exact = require('prop-types-exact')
   Link.propTypes = exact({
@@ -171,7 +171,7 @@ if (process.env.NODE_ENV === 'development') {
         const value = props[propName]
 
         if (typeof value === 'string') {
-          warnLink(`Warning: You're using a string directly inside <Link>. This usage has been deprecated. Please add an <a> tag as child of <Link>`)
+          warn(`Warning: You're using a string directly inside <Link>. This usage has been deprecated. Please add an <a> tag as child of <Link>`)
         }
 
         return null

lib/prefetch.js

@@ -1,33 +0,0 @@
-import React from 'react'
-import Link from './link'
-import Router from './router'
-import { warn, execOnce } from './utils'
-
-const warnImperativePrefetch = execOnce(() => {
-  const message = '> You are using deprecated "next/prefetch". It will be removed with Next.js 2.0.\n' +
-    '> Use "Router.prefetch(href)" instead.'
-  warn(message)
-})
-
-const wantLinkPrefetch = execOnce(() => {
-  const message = '> You are using deprecated "next/prefetch". It will be removed with Next.js 2.0.\n' +
-    '> Use "<Link prefetch />" instead.'
-  warn(message)
-})
-
-export function prefetch (href) {
-  warnImperativePrefetch()
-  return Router.prefetch(href)
-}
-
-export default class LinkPrefetch extends React.Component {
-  render () {
-    wantLinkPrefetch()
-    const props = {
-      ...this.props,
-      prefetch: this.props.prefetch !== false
-    }
-
-    return (<Link {...props} />)
-  }
-}

lib/router/router.js

@@ -4,16 +4,9 @@ import { parse, format } from 'url'
 import EventEmitter from '../EventEmitter'
 import shallowEquals from '../shallow-equals'
 import PQueue from '../p-queue'
-import { loadGetInitialProps, getURL, warn, execOnce } from '../utils'
+import { loadGetInitialProps, getURL } from '../utils'
 import { _rewriteUrlForNextExport } from './'
 
-const historyUnavailableWarning = execOnce(() => {
-  warn(`Warning: window.history is not available.`)
-})
-const historyMethodWarning = execOnce((method) => {
-  warn(`Warning: window.history.${method} is not available`)
-})
-
 export default class Router {
   static events = new EventEmitter()
 
@@ -219,14 +212,15 @@ export default class Router {
   }
 
   changeState (method, url, as, options = {}) {
-    if (typeof window.history === 'undefined') {
-      historyUnavailableWarning()
-      return
-    }
-
-    if (typeof window.history[method] === 'undefined') {
-      historyMethodWarning(method)
-      return
+    if (process.env.NODE_ENV !== 'production') {
+      if (typeof window.history === 'undefined') {
+        console.error(`Warning: window.history is not available.`)
+        return
+      }
+      if (typeof window.history[method] === 'undefined') {
+        console.error(`Warning: window.history.${method} is not available`)
+        return
+      }
     }
 
     if (method !== 'pushState' || getURL() !== as) {

lib/utils.js

@@ -1,9 +1,3 @@
-export function warn (message) {
-  if (process.env.NODE_ENV !== 'production') {
-    console.error(message)
-  }
-}
-
 export function execOnce (fn) {
   let used = false
   return (...args) => {
@@ -14,37 +8,6 @@ export function execOnce (fn) {
   }
 }
 
-export function deprecated (fn, message) {
-  // else is used here so that webpack/uglify will remove the code block depending on the build environment
-  if (process.env.NODE_ENV === 'production') {
-    return fn
-  } else {
-    let warned = false
-    const newFn = function (...args) {
-      if (!warned) {
-        warned = true
-        console.error(message)
-      }
-      return fn.apply(this, args)
-    }
-
-    // copy all properties
-    Object.assign(newFn, fn)
-
-    return newFn
-  }
-}
-
-export function printAndExit (message, code = 1) {
-  if (code === 0) {
-    console.log(message)
-  } else {
-    console.error(message)
-  }
-
-  process.exit(code)
-}
-
 export function getDisplayName (Component) {
   if (typeof Component === 'string') {
     return Component

server/index.js

@@ -3,7 +3,6 @@ import { resolve, join, sep } from 'path'
 import { parse as parseUrl } from 'url'
 import { parse as parseQs } from 'querystring'
 import fs from 'fs'
-import http, { STATUS_CODES } from 'http'
 import {
   renderToHTML,
   renderErrorToHTML,
@@ -27,7 +26,6 @@ export default class Server {
     this.dev = dev
     this.quiet = quiet
     this.router = new Router()
-    this.http = null
     const phase = dev ? PHASE_DEVELOPMENT_SERVER : PHASE_PRODUCTION_SERVER
     this.nextConfig = loadConfig(phase, this.dir, conf)
     this.distDir = join(this.dir, this.nextConfig.distDir)
@@ -87,7 +85,7 @@ export default class Server {
       .catch((err) => {
         if (!this.quiet) console.error(err)
         res.statusCode = 500
-        res.end(STATUS_CODES[500])
+        res.end('Internal Server Error')
       })
   }
 
@@ -111,15 +109,6 @@ export default class Server {
     if (this.hotReloader) {
       await this.hotReloader.stop()
     }
-
-    if (this.http) {
-      await new Promise((resolve, reject) => {
-        this.http.close((err) => {
-          if (err) return reject(err)
-          return resolve()
-        })
-      })
-    }
   }
 
   async defineRoutes () {
@@ -203,17 +192,6 @@ export default class Server {
     }
   }
 
-  async start (port, hostname) {
-    await this.prepare()
-    this.http = http.createServer(this.getRequestHandler())
-    await new Promise((resolve, reject) => {
-      // This code catches EADDRINUSE error if the port is already in use
-      this.http.on('error', reject)
-      this.http.on('listening', () => resolve())
-      this.http.listen(port, hostname)
-    })
-  }
-
   async run (req, res, parsedUrl) {
     if (this.hotReloader) {
       const {finished} = await this.hotReloader.run(req, res, parsedUrl)
@@ -232,7 +210,7 @@ export default class Server {
       await this.render404(req, res, parsedUrl)
     } else {
       res.statusCode = 501
-      res.end(STATUS_CODES[501])
+      res.end('Not Implemented')
     }
   }
 

server/lib/start-server.js

@@ -0,0 +1,14 @@
+import http from 'http'
+import Server from '../index'
+
+export default async function start (serverOptions, port, hostname) {
+  const app = new Server(serverOptions)
+  await app.prepare()
+  const srv = http.createServer(app.getRequestHandler())
+  await new Promise((resolve, reject) => {
+    // This code catches EADDRINUSE error if the port is already in use
+    srv.on('error', reject)
+    srv.on('listening', () => resolve())
+    srv.listen(port, hostname)
+  })
+}

server/lib/utils.js

@@ -0,0 +1,9 @@
+export function printAndExit (message, code = 1) {
+  if (code === 0) {
+    console.log(message)
+  } else {
+    console.error(message)
+  }
+
+  process.exit(code)
+}

server/next.js

@@ -1,5 +1,6 @@
 import Server from './'
 
+// This file is used for when users run `require('next')`
 module.exports = (opts) => {
   return new Server(opts)
 }