Svelte PWA

This is a Progressive Web App (PWA) template for Svelte apps. It lives at https://github.com/rednibcoding/svelte-pwa-template.

To create a new project based on this template using degit:

npx degit rednibcoding/svelte-pwa-template my-svelte-pwa
cd my-svelte-pwa

Note that you will need to have Node.js installed.

Get started

Install the dependencies...

cd my-svelte-pwa
npm install

...then start Rollup:

npm run dev

Navigate to localhost:5000. You should see your app running. Edit a .svelte component file in src, save it, and reload the page to see your changes.

By default, the server will only respond to requests from localhost. To allow connections from other computers, edit the sirv commands in package.json to include the option --host 0.0.0.0.

  "scripts": {
    "build": "rollup -c",
    "dev": "rollup -c -w",
    "start": "sirv public --host 0.0.0.0"
  },

Now typing either npm run dev or npm run start command, your svelte app will be opened on local network and thanks to that, you will be able to see your project state on each device connected to your network.

rollup v2.28.1
bundles src/main.js → public\build\bundle.js...
LiveReload enabled

  Your application is ready~!

  - Local:      http://0.0.0.0:5000       
  - Network:    http://10.10.10.100:5000   

────────────────── LOGS ──────────────────

PWA Configuration

• The service-worker.js and manifest.json files are in the public folder.
• You should update the icons in /public/images/icons .
• For an offline experience edit the /public/offline.html file.
• This PWA is installable, the /public/scripts/install.js file has the install configuration. Note: If you don't want to make the app installable you can remove the script from the index.html file in the public folder.

For more info on PWA's, look at this tutorial

Building and running in production mode

To create an optimised version of the app:

npm run build

You can run the newly built app with npm run start. This uses sirv, which is included in your package.json's dependencies so that the app will work when you deploy to platforms like Heroku.

Determine between production and development build during runtime

In rollup.config.js there is a flag defined called isProduction. This flag gets replaced by either false when in development build ('npm run dev') or true when in production build ('npm run build'). This way, you can check on isProduction in a .svelte component file during runtime, to determine whether you are in dev- or production build. The replacement is done via @rollup/plugin-replace which is included in your package.json's devDependencies.

Example: to log the build mode to the console

// Log build mode
console.log( "BUILD: " + (isProduction ? "Production" : "Development") );

Note: isProduction is globaly accessable from any .svelte component. So there is no need for extra imports.