Add SPA fallback template

lib/builder/generator.js

@@ -10,6 +10,7 @@ const _ = require('lodash')
 const { resolve, join, dirname, sep } = require('path')
 const { minify } = require('html-minifier')
 const Chalk = require('chalk')
+const { printWarn } = require('../common/utils')
 
 const {
   isUrl,
@@ -141,15 +142,22 @@ module.exports = class Generator {
   }
 
   async afterGenerate() {
-    const indexPath = join(this.distPath, 'index.html')
-    if (existsSync(indexPath)) {
-      // Copy /index.html to /200.html for surge SPA
-      // https://surge.sh/help/adding-a-200-page-for-client-side-routing
-      const _200Path = join(this.distPath, '200.html')
-      if (!existsSync(_200Path)) {
-        await copy(indexPath, _200Path)
-      }
+    let { fallback } = this.options.generate
+
+    // Disable SPA fallback if value isn't true or a string
+    if (fallback !== true && typeof fallback !== 'string') return
+
+    const fallbackPath = join(this.distPath, fallback)
+
+    // Prevent conflicts
+    if (existsSync(fallbackPath)) {
+      printWarn(`SPA fallback was configured, but the configured path (${fallbackPath}) already exists.`)
+      return
     }
+
+    // Render and write the SPA template to the fallback path
+    const { html } = await this.nuxt.renderRoute('/', { spa: true })
+    await writeFile(fallbackPath, html, 'utf8')
   }
 
   async initDist() {

lib/common/options.js

@@ -138,6 +138,11 @@ Options.from = function (_options) {
     options.transition.appear = true
   }
 
+  // We assume the SPA fallback path is 404.html (for GitHub Pages, Surge, etc.)
+  if (options.generate.fallback === true) {
+    options.generate.fallback = '404.html'
+  }
+
   return options
 }
 
@@ -223,6 +228,7 @@ Options.defaults = {
     concurrency: 500,
     interval: 0,
     subFolders: true,
+    fallback: '200.html',
     minify: {
       collapseBooleanAttributes: true,
       collapseWhitespace: false,

test/fallback.generate.test.js

@@ -0,0 +1,113 @@
+import test from 'ava'
+import { resolve } from 'path'
+import { existsSync } from 'fs'
+import http from 'http'
+import serveStatic from 'serve-static'
+import finalhandler from 'finalhandler'
+import rp from 'request-promise-native'
+import { intercept, interceptLog } from './helpers/console'
+import { Nuxt, Builder, Generator, Options } from '..'
+
+const port = 4015
+const url = route => 'http://localhost:' + port + route
+const rootDir = resolve(__dirname, 'fixtures/basic')
+
+let nuxt = null
+let server = null
+let generator = null
+
+// Init nuxt.js and create server listening on localhost:4015
+test.serial('Init Nuxt.js', async t => {
+  let config = require(resolve(rootDir, 'nuxt.config.js'))
+  config.rootDir = rootDir
+  config.buildDir = '.nuxt-spa-fallback'
+  config.dev = false
+  config.build.stats = false
+
+  const logSpy = await interceptLog(async () => {
+    nuxt = new Nuxt(config)
+    const builder = new Builder(nuxt)
+    generator = new Generator(nuxt, builder)
+
+    await generator.generate()
+  })
+  t.true(logSpy.calledWithMatch('DONE'))
+
+  const serve = serveStatic(resolve(__dirname, 'fixtures/basic/dist'))
+  server = http.createServer((req, res) => {
+    serve(req, res, finalhandler(req, res))
+  })
+  server.listen(port)
+})
+
+test.serial('default creates /200.html as fallback', async t => {
+  const html = await rp(url('/200.html'))
+  t.false(html.includes('<h1>Index page</h1>'))
+  t.false(html.includes('data-server-rendered'))
+  t.true(existsSync(resolve(__dirname, 'fixtures/basic/dist', '200.html')))
+  t.false(existsSync(resolve(__dirname, 'fixtures/basic/dist', '404.html')))
+})
+
+test.serial('nuxt re-generating with generate.fallback = false', async t => {
+  const logSpy = await interceptLog(async () => {
+    nuxt.options.generate.fallback = false
+    await generator.generate()
+  })
+  t.true(logSpy.calledWithMatch('DONE'))
+})
+
+test.serial('false creates no fallback', async t => {
+  const error = await t.throws(rp(url('/200.html')))
+  t.true(error.statusCode === 404)
+  t.true(error.response.body.includes('Cannot GET /200.html'))
+  t.false(existsSync(resolve(__dirname, 'fixtures/basic/dist', '200.html')))
+  t.false(existsSync(resolve(__dirname, 'fixtures/basic/dist', '404.html')))
+})
+
+test.serial('generate.fallback = true is transformed to /404.html', async t => {
+  nuxt.options.generate.fallback = true
+  const options = Options.from(nuxt.options)
+  t.is(options.generate.fallback, '404.html')
+})
+
+test.serial('nuxt re-generating with generate.fallback = "spa-fallback.html"', async t => {
+  const logSpy = await interceptLog(async () => {
+    nuxt.options.generate.fallback = 'spa-fallback.html'
+    await generator.generate()
+  })
+  t.true(logSpy.calledWithMatch('DONE'))
+})
+
+test.serial('"spa-fallback.html" creates /spa-fallback.html as fallback', async t => {
+  const html = await rp(url('/spa-fallback.html'))
+  t.false(html.includes('<h1>Index page</h1>'))
+  t.false(html.includes('data-server-rendered'))
+  t.true(
+    existsSync(resolve(__dirname, 'fixtures/basic/dist', 'spa-fallback.html'))
+  )
+  t.false(existsSync(resolve(__dirname, 'fixtures/basic/dist', '404.html')))
+  t.false(existsSync(resolve(__dirname, 'fixtures/basic/dist', '200.html')))
+})
+
+test.serial('nuxt re-generating with generate.fallback = "index.html"', async t => {
+  const {log: logSpy, warn: warnSpy} = await intercept({warn: true, log: true}, async () => {
+    nuxt.options.generate.fallback = 'index.html'
+    await generator.generate()
+  })
+  t.true(warnSpy.calledWithMatch('WARN')) // Must emit warnning
+  t.true(logSpy.calledWithMatch('DONE'))
+})
+
+test.serial('"index.html" creates /index.html as fallback', async t => {
+  const html = await rp(url('/index.html'))
+  t.true(html.includes('<h1>Index page</h1>'))
+  t.true(html.includes('data-server-rendered'))
+  t.true(existsSync(resolve(__dirname, 'fixtures/basic/dist', 'index.html')))
+  t.false(existsSync(resolve(__dirname, 'fixtures/basic/dist', '404.html')))
+  t.false(existsSync(resolve(__dirname, 'fixtures/basic/dist', '200.html')))
+})
+
+// Close server and ask nuxt to stop listening to file changes
+test.after.always('Closing server', async t => {
+  await server.close()
+})