feat(workbox): rewrite with better template support

packages/workbox/index.js

@@ -1,76 +1,149 @@
 const path = require('path')
 const swBuild = require('workbox-build')
+const { readFileSync, writeFileSync } = require('fs')
+const hashSum = require('hash-sum')
+const debug = require('debug')('nuxt:pwa:workbox')
 
 const fixUrl = url => url.replace(/\/\//g, '/').replace(':/', '://')
 const isUrl = url => url.indexOf('http') === 0 || url.indexOf('//') === 0
 
-module.exports = function nuxtWorkbox (options) {
+// =============================================
+// workboxModule
+// =============================================
+
+module.exports = function nuxtWorkbox (moduleOptions) {
+  const options = Object.assign({}, moduleOptions, this.options.workbox)
+  const ctx = { options }
+
   if (this.options.dev) {
     return
   }
 
-  // routerBase and publicPath
+  this.nuxt.plugin('build', builder => {
+    debug('Adding workbox')
+    getRouterBase.call(this, ctx)
+    workboxInject.call(this, ctx)
+    emitAssets.call(this, ctx)
+    addTemplates.call(this, ctx)
+  })
+}
+
+// =============================================
+// getRouterBase
+// =============================================
+
+function getRouterBase (ctx) {
   const routerBase = this.options.router.base
   let publicPath = fixUrl(`${routerBase}/${this.options.build.publicPath}`)
   if (isUrl(this.options.build.publicPath)) { // CDN
     publicPath = this.options.build.publicPath
     if (publicPath.indexOf('//') === 0) {
-      publicPath = '/' + publicPath // escape fixUrl
+      publicPath = '/' + publicPath // Escape fixUrl
     }
   }
 
-  const swFileName = 'sw.js'
+  ctx.routerBase = routerBase
+  ctx.publicPath = publicPath
+}
+
+// =============================================
+// addTemplates
+// =============================================
+
+function addTemplates (ctx) {
+  // Add sw.template.js
+  this.addTemplate({
+    src: path.resolve(__dirname, 'templates/sw.template.js'),
+    fileName: 'sw.template.js',
+    options: {
+      importPath: ctx.wbDst,
+      wb: ctx.workboxOptions
+    }
+  })
+
+  // Add sw.plugin.js
+  const swURL = `${ctx.routerBase}/${ctx.options.swURL || 'sw.js'}`
+  this.addPlugin({
+    src: path.resolve(__dirname, 'templates/sw.plugin.js'),
+    ssr: false,
+    fileName: 'sw.plugin.js',
+    options: {
+      swURL: fixUrl(swURL),
+      swScope: fixUrl(`${ctx.routerBase}/`)
+    }
+  })
+}
 
-  // Use swBuild to generate sw file
-  // We set dest to static dir that is served as / to allow global sw scope
+// =============================================
+// emitAssets
+// =============================================
+
+function emitAssets (ctx) {
+  const assets = []
+  const emitAsset = (path, name, ext = 'js') => {
+    const source = readFileSync(path)
+    const hash = hashSum(source)
+    const dst = `${name}.${hash}.${ext}`
+    assets.push({source, dst})
+    return dst
+  }
+
+  // Write assets after build
+  this.nuxt.plugin('build', builder => {
+    builder.plugin('built', () => {
+      assets.forEach(({source, dst}) => {
+        writeFileSync(path.resolve(this.options.buildDir, 'dist', dst), source, 'utf-8')
+      })
+    })
+  })
+
+  // workbox.js
+  let wbPath = require.resolve('workbox-sw')
+  if (ctx.options.dev) {
+    wbPath = wbPath.replace(/prod/g, 'dev')
+  }
+  ctx.wbDst = fixUrl(ctx.publicPath + '/' + emitAsset(wbPath, 'workbox' + (ctx.options.dev ? '.dev' : '')))
+}
+
+// =============================================
+// workboxInject
+// =============================================
+
+function workboxInject (ctx) {
   // https://workboxjs.org/reference-docs/latest/module-workbox-build.html#.generateSW
-  const workboxOptions = Object.assign({
-    swDest: path.resolve(this.options.srcDir, 'static', swFileName),
+  ctx.workboxOptions = Object.assign({
+    swSrc: path.resolve(this.options.buildDir, 'sw.template.js'),
+    swDest: path.resolve(this.options.srcDir, 'static', 'sw.js'),
     directoryIndex: '/',
     cacheId: process.env.npm_package_name + '_' + process.env.npm_package_version,
     clientsClaim: true,
     globPatterns: ['**/*.{js,css}'],
     globDirectory: path.resolve(this.options.buildDir, 'dist'),
     modifyUrlPrefix: {
-      '': fixUrl(publicPath)
+      '': fixUrl(ctx.publicPath)
     },
     runtimeCaching: [
       // Cache routes if offline
       {
-        urlPattern: fixUrl(routerBase + '/**'),
+        urlPattern: fixUrl(ctx.routerBase + '/**'),
         handler: 'networkFirst'
       },
       // Cache other _nuxt resources runtime
       // They are hashed by webpack so are safe to loaded by cacheFirst handler
       {
-        urlPattern: fixUrl(publicPath + '/**'),
+        urlPattern: fixUrl(ctx.publicPath + '/**'),
         handler: 'cacheFirst'
       }
     ]
-  }, options)
+  }, ctx.options)
 
-  // Use nuxt plugins to prevent race conditions with webpack plugin
-  // (https://github.com/nuxt-community/modules/issues/110)
   this.nuxt.plugin('build', builder => {
     builder.plugin('built', () => {
-      if (workboxOptions.swSrc) {
-        return swBuild.injectManifest(workboxOptions)
-      } else {
-        return swBuild.generateSW(workboxOptions)
-      }
+      const opts = Object.assign({}, ctx.workboxOptions)
+      delete opts.runtimeCaching
+      return swBuild.injectManifest(opts)
     })
   })
-
-  // Register runtime plugin
-  const swURL = `${routerBase}/${options.swURL || swFileName}`
-  this.addPlugin({
-    src: path.resolve(__dirname, 'plugin.js'),
-    ssr: false,
-    options: {
-      swURL: fixUrl(swURL),
-      swScope: fixUrl(`${routerBase}/`)
-    }
-  })
 }
 
 module.exports.meta = require('./package.json')

packages/workbox/templates/sw.template.js

@@ -0,0 +1,13 @@
+importScripts('<%= options.importPath %>')
+
+const workboxSW = new self.WorkboxSW({
+  cacheId: '<%= options.wb.cacheId %>',
+  clientsClaim: <%= options.wb.clientsClaim %>,
+  directoryIndex: '<%= options.wb.directoryIndex %>'
+})
+
+workboxSW.precache([])
+
+<% options.wb.runtimeCaching.forEach(r => { %>
+workboxSW.router.registerRoute('<%= r.urlPattern %>', workboxSW.strategies.<%= r.handler %>({}), 'GET')
+<% }) %>