Modern WebApps - Infrastructure: Vue, Parcel & Workbox
Tags: javascript, webdev, tutorial, vue
Published: 2019-04-17 06:46:54

---
canonical_url: https://greekdeveloper.com/2019/vue-template
---

Single Page Applications (SPA) are web applications that are contained in a single web page, providing a seamless navigation experience due to not having to download and parse the html for each page. Progressive Web Applications (PWA) are web applications that, using a service worker "proxy" and a manifest file, provide the necessary infrastructure to allow cashing of the application by the browser in order to be usable in poor, or no-network conditions. All modern browsers and OSes allow PWAs to be "installed" locally and, thus, provide for a native-like user experience.
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A PWA is often a viable alternative to building a native application, especially for small teams, since most app stores now accept PWAs and all major OSes (Windows, Android, iOS) allow PWAs to be installed and appear on the desktop. PWAs open instantly and the browser can be directed to hide it's controls providing a native-like look and feel. 

Modern tooling can simplify development but setting it up can be a time-consuming task. Let's see how to setup a SPA & PWA project. The scope of this tutorial is to describe the setup and not each framework/tools specifically - Each of these tools has extended documentation that explains how each works.

---
## Framework & Tools


#### Vue.js

We will use the Vue ecosystem for the heavylifting:

- **[Vue.js](https://vuejs.org/)** will handle our views by providing a declarative approach in defining them and seperating the code in single-file-components, 
- **[VueX](https://vuex.vuejs.org)** will be used for state management
- **[Vue Router](https://router.vuejs.org/)** will be used to handle the SPA routes


#### Node.js

**[node.js](https://nodejs.org)** will provide support for the bundling utilities and all other utilities that might be required


#### Parcel.js

**[Parcel](https://parceljs.org/)** bundler will be used to build and bundle the application


#### Workbox

**[Workbox](https://developers.google.com/web/tools/workbox/)** will handle the service-worker details.

---
## Files layout

- `./src` will contain all source code for this project.
  - `./src/web` will contain the source code for the web application (the html client).
  - `./src/db` (optional) will contain any database initialization scripts
  - `./src/server` (optional) will contain any server-side projects
- `./dist` will contain all generated artifacts and should be ignored in git
  - `./dist/web` will contain the builded and bundled web application.
  - `./dist/db` (optional) will contain any artifacts generated by the database scrits
  - `./dist/server`(optional) will contain any server-side projects (compiled)
- `./.cache` will be generated by parcel and should be ignored in git
- `./node_modules` will be generated by npm or parcel and should be ingored in git




---
## The code 

The code can be found in [project's github repo](https://github.com/sarmis/greekdev-template-vue-spa)

#### Javascript dependencies

![](https://greekdeveloper.com/2019/vue-template/dependencygraph.svg)


#### Entry point (index.html)

`./src/web/index.html` is our entry point and just links everything together

- `<link rel="manifest" href="./manifest.webmanifest">` links the *.webmanifest* file
- `<div id="vueapp"></div>` defines vue mounting point          
- `<script src="./index.js"></script>` loads the script that contains the vue application
- `navigator.serviceWorker.register('/service-worker.js');` registers the service worker script

``` html
<!DOCTYPE html>
<html lang="en">
    <head>
        <meta charset="UTF-8">
        <meta name="viewport" content="width=device-width, initial-scale=1.0">
        <meta http-equiv="X-UA-Compatible" content="ie=edge">
        <link rel="manifest" href="./manifest.webmanifest">
        
        <title>Vue.js Single Page Application Template</title>       
    </head>

    <body>
        <div id="vueapp"></div>          
        
        <script src="./index.js"></script>
        <script>
            if ('serviceWorker' in navigator) {
                window.addEventListener('load', () => {
                    navigator.serviceWorker.register('/service-worker.js');
                });
            }            
        </script>
    </body>
</html>
```

#### Manifest

`./src/web/manifest.webmanifest` describes the application and is required for the application to be considered a PWA.
It's important to maintain the *.webmanifest* extension for parcel compatibility. 

``` json
{
    "name": "My application name",  
    "short_name": "app",

    "start_url": "/",
    "background_color": "#3367D6",
    "display": "standalone",
    "scope": "/",
    "theme_color": "#3367D6",
    
    "icons": [
        {
            "src": "/res/app-256.png",
            "type": "image/png",
            "sizes": "256x256"
        }
    ]
}
```

#### Service Worker (Workbox)

`./src/web/service-worker.js` implements the service worker that is requred for considering the application to be a PWA. Google's workbox is used. Workbox defines multiple stategies (network-first, cache-first, and Stale-while-revalidate). In this example all resources are served using the network-first strategy since this is the most responsice approach and maintains the capability to work offline.

``` javascript
console.log("service-worker.js")
// import service worker script
importScripts('https://storage.googleapis.com/workbox-cdn/releases/4.2.0/workbox-sw.js');

// Network First
[ 
    '/$',  // Index 
    '/*',  // Anything in the same host
    '.+/*' // Anything in any host 
]
.forEach(mask => {
    workbox.routing.registerRoute(
        new RegExp(mask),
        new workbox.strategies.NetworkFirst( { cacheName: 'dynamic' } ) 
    );
});
```

#### Vue binding

`./src/web/index.js` is used to bind the vue application and our css (in scss). It imports the Vue framework, our vue application code (`app.vue`) and our styles (`styles.scss`) - All these files are located in `./src/web/` but we are using relative paths in the imports. Finally we mount our vue application to the corresponding div element.

``` javascript
import Vue from 'vue';

import App from './app.vue';
import './style.scss'

new Vue(App).$mount('#vueapp')
```

#### Vue Application

`./src/web/app.vue` contains our vue application as a single file component.

In the `<template>`  we construct a simple navigational menu and the *router-view* which is the host for our single page application, all other pages are mounted in the router-view element. In this template we are using `pug` insteand of html.

In the `<script>` we import the vue framework and two custom modules, the `_router.js` and the `_store.js` and we create our vue application by extending the default vue application with the *store* and *router* modules we just loaded.

In the `<style>` we providing some local (scoped) styling for the menu using *scss* (which out bundler will convert to css)


``` html
<template lang="pug">
    div
        nav.navbar
            router-link(to="/") home
            router-link(to="/profile") profile
            router-link(to="/about") about
        router-view
</template>


<script>
    import Vue from "vue";
    import {router} from './_router.js';
    import {store} from './_store.js'
   
    export default Vue.extend({ 
        store: store,
        router: router    
    });    
</script>


<style lang="scss" scoped>
    
    .navbar {
        text-align: center;
        
        * + * {
            margin-left: 8px;
        }
    }
</style>

```

#### Router

`./src/web/_router.js` configures and initializes *vue-router* by loading all pages and declaring their routes. 

``` javascript
import Vue from "vue";
    
import VueRouter from 'vue-router';

Vue.use(VueRouter)

// 1. Import Components
import home    from './vues/home.vue'
import about   from './vues/about.vue'
import profile from './vues/profile.vue'

// 2. Define some routes
const routes = [
    { path: '/'       , component: home    },   
    { path: '/profile', component: profile },
    { path: '/about'  , component: about   }
]

// 3. Create & Export the router 
export const router = new VueRouter({
    routes: routes
})
```

#### Store

`./src/web/_store.js`  configures and initializes the vuex store module. It declares the global state and the available mutations. The vuex allows for global state to be modified by all view components (through the mutations) while mainting the reactivity of the framework. (ie commiting a mutation will update all components that are affected by the state change).

``` javascript
import Vue from 'vue'
import Vuex from 'vuex';

Vue.use(Vuex);

export const store = new Vuex.Store({
    state: {
        name: 'Unknown'
    },

    // Usege: $store.commit('mutationan', parameter)
    mutations: {
        setName(state, name) {
            Vue.set(state, 'name', name);
        }
    }
});
```
#### Pages

We have three pages in our example, *home* and *about* are almost identical, both are rendering the *name* property of the store.

*profile* provides an input box where the user an type his name and instantly updates the global state when the value of the input changes.

`./src/web/vues/about.vue`

``` html
<template lang="pug">
    div 
        h1 About
        p  Welcome: {{$store.state.name}}
</template>

<script>
    export default {
        
    }
</script>
```

`./src/web/vues/home.vue`
``` html
<template>
    <div> 
        <h1>Home</h1> 
        <p> Welcome: {{$store.state.name}}</p>
       
    </div>   
</template>


<script>
    export default {
    }
</script>
```

`./src/web/profile.vue`
``` html
<template lang="pug">
  div 
    h1 Profile
    p  Welcome: {{$store.state.name}}
    div.form 
      table
        tr
          td Name
          td
            input(:value="$store.state.name" @input="$store.commit('setName',$event.target.value)")
</template>

<script>
    export default {
        
    }
</script>
<style lang="scss" scoped>
    .form {
        display: flex;
        justify-content: center;
    }
</style>
```

## Developing

The following steps are required in order to develop on this template

- Download or clone the [code](https://github.com/sarmis/greekdev-template-vue-spa)

- Install parcel `npm i -g parcel-bundler`
- Install project dependencies `npm install` (in project root)
- Run the dev script `npm run dev`


######[Original post at greek developer](https://greekdeveloper.com/2019/vue-template/)