generate with child process

lib/generate.js

@@ -11,6 +11,8 @@ const copy = pify(fs.copy)
 const remove = pify(fs.remove)
 const writeFile = pify(fs.writeFile)
 const mkdirp = pify(fs.mkdirp)
+const numWorkers = require('os').cpus().length
+const childProcess = require('child_process')
 
 const defaults = {
   dir: 'dist',
@@ -39,6 +41,7 @@ const defaults = {
 }
 
 export default async function () {
+  const child = process.argv[3]
   const s = Date.now()
   let errors = []
   /*
@@ -49,6 +52,7 @@ export default async function () {
   var srcBuiltPath = resolve(this.dir, '.nuxt', 'dist')
   var distPath = resolve(this.dir, this.options.generate.dir)
   var distNuxtPath = join(distPath, (isUrl(this.options.build.publicPath) ? '' : this.options.build.publicPath))
+  if (!child) {
     /*
     ** Launch build process
     */
@@ -68,6 +72,7 @@ export default async function () {
     }
     await copy(srcBuiltPath, distNuxtPath)
     debug('Static & build files copied')
+  }
   if (this.options.router.mode !== 'hash') {
     // Resolve config.generate.routes promises before generating the routes
     try {
@@ -82,6 +87,7 @@ export default async function () {
     ** Generate html files from routes
     */
     generateRoutes.forEach((route) => {
+      this.routes || (this.routes = [])
       if (this.routes.indexOf(route) < 0) {
         this.routes.push(route)
       }
@@ -91,6 +97,26 @@ export default async function () {
   ** Generate only index.html for router.mode = 'hash'
   */
   let routes = (this.options.router.mode === 'hash') ? ['/'] : this.routes
+
+  const prmiseArray = []
+  if (!child) {
+    const workers = routes.length < numWorkers ? routes.length : numWorkers
+    for (let i = 0; i < workers; i++) {
+      prmiseArray.push(new Promise((resolve) => {
+        childProcess.exec(`node ./bin/nuxt generate . child-${i}`, (err, stdout, stderr) => {
+          if (err) {
+            debug(`child-${i} has error ${err}`)
+          } else {
+            debug(`child-${i} generate success`)
+          }
+          resolve(`child-${i} generate finish`)
+        })
+      }))
+    }
+  } else {
+    const start = parseInt(child.split('-')[1])
+    const quantity = Math.ceil(routes.length / (numWorkers - 1))
+    routes = routes.splice(start * quantity, quantity)
     while (routes.length) {
       let n = 0
       await Promise.all(routes.splice(0, 500).map(async (route) => {
@@ -122,6 +148,8 @@ export default async function () {
         await writeFile(path, html, 'utf8')
       }))
     }
+  }
+  await Promise.all(prmiseArray)
   // Add .nojekyll file to let Github Pages add the _nuxt/ folder
   // https://help.github.com/articles/files-that-start-with-an-underscore-are-missing/
   const nojekyllPath = resolve(distPath, '.nojekyll')