separate server/client api creation and add sw-precache plugin

build/webpack.client.config.js

@@ -3,6 +3,11 @@ const base = require('./webpack.base.config')
 const vueConfig = require('./vue-loader.config')
 
 const config = Object.assign({}, base, {
+  resolve: {
+    alias: {
+      'create-api': './create-api-client.js'
+    }
+  },
   plugins: (base.plugins || []).concat([
     // strip comments in Vue code
     new webpack.DefinePlugin({
@@ -15,6 +20,7 @@ if (process.env.NODE_ENV === 'production') {
   // Use ExtractTextPlugin to extract CSS into a single file
   // so it's applied on initial render
   const ExtractTextPlugin = require('extract-text-webpack-plugin')
+  const SWPrecachePlugin = require('sw-precache-webpack-plugin')
 
   // vueConfig is already included in the config via LoaderOptionsPlugin
   // here we overwrite the loader config for <style lang="stylus">
@@ -37,6 +43,10 @@ if (process.env.NODE_ENV === 'production') {
       compress: {
         warnings: false
       }
+    }),
+    new SWPrecachePlugin({
+      cacheId: 'vue-hn',
+      filename: 'service-worker.js'
     })
   )
 }

build/webpack.server.config.js

@@ -9,6 +9,11 @@ module.exports = Object.assign({}, base, {
     filename: 'server-bundle.js',
     libraryTarget: 'commonjs2'
   }),
+  resolve: {
+    alias: {
+      'create-api': './create-api-server.js'
+    }
+  },
   externals: Object.keys(require('../package.json').dependencies),
   plugins: [
     new webpack.DefinePlugin({

package.json

@@ -22,6 +22,7 @@
     "lru-cache": "^4.0.1",
     "serialize-javascript": "^1.3.0",
     "serve-favicon": "^2.3.0",
+    "sw-precache-webpack-plugin": "^0.5.1",
     "vue": "^2.0.0",
     "vue-router": "^2.0.0",
     "vue-server-renderer": "^2.0.0",

src/client-entry.js

@@ -7,3 +7,8 @@ store.replaceState(window.__INITIAL_STATE__)
 
 // actually mount to DOM
 app.$mount('#app')
+
+// service worker
+if (process.env.NODE_ENV === 'production' && 'serviceWorker' in navigator) {
+  navigator.serviceWorker.register('/dist/service-worker.js')
+}

src/store/api.js

-import Firebase from 'firebase'
-import LRU from 'lru-cache'
+// this is aliased in webpack config based on server/client build
+import api from 'create-api'
 
-const inBrowser = typeof window !== 'undefined'
-
-// When using bundleRenderer, the server-side application code runs in a new
-// context for each request. To allow caching across multiple requests, we need
-// to attach the cache to the process which is shared across all requests.
-const cache = inBrowser
-  ? null
-  : (process.__API_CACHE__ || (process.__API_CACHE__ = createCache()))
-
-function createCache () {
-  return LRU({
-    max: 1000,
-    maxAge: 1000 * 60 * 15 // 15 min cache
-  })
+// warm the front page cache every 15 min
+if (api.cachedIds) {
+  warmCache()
 }
 
-// create a single api instance for all server-side requests
-const api = inBrowser
-  ? new Firebase('https://hacker-news.firebaseio.com/v0')
-  : (process.__API__ || (process.__API__ = createServerSideAPI()))
-
-function createServerSideAPI () {
-  const api = new Firebase('https://hacker-news.firebaseio.com/v0')
-
-  // cache the latest story ids
-  api.__ids__ = {}
-  ;['top', 'new', 'show', 'ask', 'job'].forEach(type => {
-    api.child(`${type}stories`).on('value', snapshot => {
-      api.__ids__[type] = snapshot.val()
-    })
-  })
-
-  // warm the front page cache every 15 min
-  warmCache()
-  function warmCache () {
-    fetchItems((api.__ids__.top || []).slice(0, 30))
+function warmCache () {
+  fetchItems((api.cachedIds.top || []).slice(0, 30))
   setTimeout(warmCache, 1000 * 60 * 15)
-  }
-
-  return api
 }
 
 function fetch (child) {
+  const cache = api.cachedItems
   if (cache && cache.has(child)) {
     return Promise.resolve(cache.get(child))
   } else {
@@ -60,8 +29,8 @@ function fetch (child) {
 }
 
 export function fetchIdsByType (type) {
-  return api.__ids__ && api.__ids__[type]
-    ? Promise.resolve(api.__ids__[type])
+  return api.cachedIds && api.cachedIds[type]
+    ? Promise.resolve(api.cachedIds[type])
     : fetch(`${type}stories`)
 }
 

src/store/create-api-client.js

+import Firebase from 'firebase'
+
+export default new Firebase('https://hacker-news.firebaseio.com/v0')

src/store/create-api-server.js

+import Firebase from 'firebase'
+import LRU from 'lru-cache'
+
+let api
+
+if (process.__API__) {
+  api = process.__API__
+} else {
+  api = process.__API__ = new Firebase('https://hacker-news.firebaseio.com/v0')
+
+  // fetched item cache
+  api.cachedItems = LRU({
+    max: 1000,
+    maxAge: 1000 * 60 * 15 // 15 min cache
+  })
+
+  // cache the latest story ids
+  api.cachedIds = {}
+  ;['top', 'new', 'show', 'ask', 'job'].forEach(type => {
+    api.child(`${type}stories`).on('value', snapshot => {
+      api.cachedIds[type] = snapshot.val()
+    })
+  })
+}
+
+export default api