vue-cli-plugin-workbox-pwa

BETA - submitted PR to Vue CLI https://github.com/vuejs/vue-cli/pull/6497

A Vue CLI Plugin with advanced support for workbox 6.x, Vue 3, and webpack 4. Includes the ability to debug the service worker locally.

How is this different from the vue-cli-plugin-pwa?

vue-cli-plugin-pwa depends on register-service-worker but this does not. The register-service-worker makes several assumptions about how the PWA should work, but this does not meet advanced use cases like cached apis, cache first, etc.
vue-cli-plugin-pwa does not provide a way to easily debug the service worker. This plugin does. It makes use of a new environment variable to enable NODE_ENV=development and injecting the manifest with customizations.
We started with some of the manifest features of vue-cli-plugin-pwa. Because this is a more fully featured pwa, we start with the assumption that InjectManifest mode of Workbox is needed.
There is no HMR when running the pwalocalserve mode because the purpose of this mode is strictly for service worker debugging and not application changes.This means if you make changes to the service worker code (or application) while running in pwalocalserve, you will need to stop the app and re-run it and refresh the browser. For application changes, continue using development mode.

Set up

The scripts commands expects a global install of npm serve.

Run: npm install -g serve.

Configuration

Configuration is handled via the pwa property of either the vue.config.js file, or the "vue" field in package.json.

pwa.workboxPluginMode

This allows you to choose between the two modes supported by the underlying workbox-webpack-plugin.
- 'InjectManifest' (default), allows you to start with an existing service worker file, and creates a copy of that file with a "precache manifest" injected into it.
- 'GenerateSW' will lead to a new service worker file being created each time you rebuild your web app.
The "Which Plugin to Use?" guide can help you choose between the two modes.
pwa.workboxOptions

These options are passed on through to the underlying workbox-webpack-plugin.

For more information on what values are supported, please see the guide for GenerateSW or for InjectManifest.
pwa.name
- Default: "name" field in package.json
  
  Used as the value for the apple-mobile-web-app-title meta tag in the generated HTML. Note you will need to edit public/manifest.json to match this.
pwa.themeColor
- Default: '#4DBA87'
pwa.msTileColor
- Default: '#000000'
pwa.appleMobileWebAppCapable
- Default: 'no'
  
  This defaults to 'no' because iOS before 11.3 does not have proper PWA support. See this article for more details.
pwa.appleMobileWebAppStatusBarStyle
- Default: 'default'
pwa.assetsVersion
- Default: ''
  
  This option is used if you need to add a version to your icons and manifest, against browser’s cache. This will append ?v=<pwa.assetsVersion> to the URLs of the icons and manifest.
pwa.manifestPath
- Default: 'manifest.json'
  
  The path of app’s manifest. If the path is an URL, the plugin won't generate a manifest.json in the dist directory during the build.
pwa.manifestOptions
- Default: {}
  
  The object will be used to generate the manifest.json
  
  If the following attributes are not defined in the object, the options of pwa or default options will be used instead.
  - name: pwa.name
  - short_name: pwa.name
  - display: 'standalone'
  - theme_color: pwa.themeColor
  - start_url: '/'
    
    By default, the start url is set to '/'. If it is set to '.', it will work fine in a web browser or when installed on Windows, but will result in a blank when installed on iOS or Android.
    
    The router will also need to have an entry for path: '/'. This will meet the requirements for a good start_url in Lighthouse.
pwa.manifestCrossorigin
- Default: undefined
  
  Value for crossorigin attribute in manifest link tag in the generated HTML. You may need to set this if your PWA is behind an authenticated proxy. See cross-origin values for more details.

pwa.iconPaths

Defaults:

{
  faviconSVG: 'img/icons/favicon.svg',
  favicon32: 'img/icons/favicon-32x32.png',
  favicon16: 'img/icons/favicon-16x16.png',
  appleTouchIcon: 'img/icons/apple-touch-icon-152x152.png',
  maskIcon: 'img/icons/safari-pinned-tab.svg',
  msTileImage: 'img/icons/msapplication-icon-144x144.png'
}

Change these values to use different paths for your icons. You can use null as a value and that icon will not be included.

Example Configuration

// Inside vue.config.js
module.exports = {
  // ...other vue-cli plugin options...
  pwa: {
    name: 'My App',
    themeColor: '#4DBA87',
    msTileColor: '#000000',
    appleMobileWebAppCapable: 'yes',
    appleMobileWebAppStatusBarStyle: 'black',

    manifestOptions: {
      start_url: '/'
    },
    // configure the workbox plugin
    workboxPluginMode: 'InjectManifest',
    workboxOptions: {
      // swSrc is required in InjectManifest mode.
      swSrc: './src/sw.js',
      swDest: 'service-worker.js',
      // ...other workbox options
    }
  }
}

Installing in an Already Created Project

vue add workbox-pwa

Injected dependencies and devDependencies

"dependencies": {
  "workbox-cacheable-response": "^6.1.5",
  "workbox-core": "^6.1.5",
  "workbox-expiration": "^6.1.5",
  "workbox-routing": "^6.1.5",
  "workbox-strategies": "^6.1.5",
  "workbox-window": "^6.1.5"
},
"devDependencies": {
  "workbox-webpack-plugin": "^6.1.5"
}

Injected webpack-chain Rules

config.plugin('workbox')
config.plugin('html') title attribute is added to match the pwa.name

Injected files

public/img/ Default app icons are added.
public/ Default robots.txt is added.
src/sw.js Default service worker file is added with:
- Common caching scenarios for index.html, css, js, images.
- Workbox's syntax for injecting the manifest. precacheAndRoute(self.__WB_MANIFEST)
- Workbox clear cache for outdated versions of Workbox. cleanupOutdatedCaches()
.env
- If it doesn't exist, then it's created with the new variable VUE_APP_PWA_LOCAL_SERVE=false.
- If it does, the new variable VUE_APP_PWA_LOCAL_SERVE=false is added.
- This prevents any environments other than pwalocalserve from using that variable.
.env.pwalocalserve
- Sets NODE_ENV=development so Workbox will allow debugging of the service worker.
- Sets VUE_APP_DEBUG=true so we get Vue debugging.
- SetsVUE_APP_PWA_LOCAL_SERVE=true so we can actually debug the service worker and by passes the "NoopServiceWorker" middleware. Also injects the manifest.
main.js
- Adds the import statement to register the service worker and calls the register method.
- Adds console log statements so you can verify in your browser console that PWA Local Serve is true.
```
PWA Local Serve: true
Node Env: development
```
service-worker/register-service-worker.js
- The code to create an instance of the service worker and register it.
- Also includes code for updating the service worker:
  - Auto Update - checks for updates to the service worker at an interval. The default is 1 hour.
  - Manual Update - provides a prompt to the user to manually update the app when a new version of the service worker is available. Depending on your caching strategy, you may want to add code to handle things like flushing the cache, unsaved updates (especially if using Offline Cache), etc.

Using pwalocalserve

Run npm run pwa-serve
Navigate to the url. Notice in the console, you should see workbox messages. The following browser console messages let you know you are in the pwalocalserve mode.
```
PWA Local Serve: true
Node Env: development
```
If you make changes to the service worker code in src/sw.js or src/service-worker/register-service-worker.js, you will need to stop the application and re-run npm run pwa-serve, then refresh the browser. In Chrome Dev Tools under the Application Tab >> Service Worker, you should see there is a new version of the service worker waiting to be activated. Depending on what features you've enabled, the service worker could prompt the user (manual update). You can, of course, customize this code to what you need.

License

MIT