Web Component: j-ServiceWorker

j-ServiceWorker

• PERFECT EXAMPLE https://github.com/totaljs/emptyproject-pwa
• This component is a little bit special. First of all, you need put the code below into file e.g. sw-jcomponent.js and place it to the public (e.g. myproject/public/sw-jcomponent.js)

var prefix='jc';function hash(s,unsigned){var hash=0,i,char;if(!s.length)return hash;var l=s.length;for(i=0;i<l;i++){char=s.charCodeAt(i);hash=((hash<<5)-hash)+char;hash|=0;}return unsigned?hash>>>0:hash}self.addEventListener('install',()=>{self.skipWaiting()});self.addEventListener('message',function(e){if(e.data.action==='jc-sw'){var data=e.data.data;data.name=prefix+'-'+data.version+'-'+hash(data.assets.toString(),true);addcache(e.data.data)}});self.addEventListener('fetch',function(e){e.respondWith(fetch(e.request).catch(function(){return caches.match(e.request).then(function(response){if(response)return response;if(e.request.mode==='navigate'||(e.request.method==='GET'&&e.request.headers.get('accept').includes('text/html')))return caches.match('jc-offline-fallback')})}))});function addcache(data){caches.open(data.name).then(function(cache){if(data.assets&&data.assets.length)cache.addAll(data.assets);if(data.fallback){fetch(data.fallback,{mode:'no-cors'}).then(function(response){return cache.put('jc-offline-fallback',response)})}}).then(function(){caches.keys().then(function(keys){return Promise.all(keys.map(function(key){if(data.name!==key)return caches.delete(key)}))})})}

• The component will communicate with this service worker code.

Configuration:

• expire {String} expiration data from users storage (default: 1 day) we don't recommend changing this
• debug {Boolean} enables debug mode. It'll refresh assets every reload (so you don't need to change the version) (default: false)
• datasource {String} path to data-source (data-source is a object)

Datasource structure:

{
    version: '1.00',
    fallback: '/',
    assets: [
        '/js/default.js'
    ]
}

Good to know:

• PATH can be used as dynamic version. It'll refresh assets instantly (without page reloading) e.g. SET('version', '1.35')
• After add/remove something from assets, you doesn't need to increase version
• fallback performs offline version of html. e.g. fallback: '/offline.html'
• Assets can be everything: fonts, partial pages, css files, javascript files
• It's work only in Single Page Applications like this or this

Usage:

<div data---="serviceworker__version__datasource:mysource"></div>

<script>
    var version = '1.34';
    var mysource = {
        version: version,
        fallback: '/',
        assets: [
            '/pages/settings.html',
            '/pages/articles.html',
            '/pages/dashboard.html'
        ]
    };
</script>

Author

• Denis Granec info@totalavengers.com
• License