/* ===========================================================
* docsify sw.js
* ===========================================================
* Copyright 2016 @huxpro
* Licensed under Apache 2.0
* Register service worker.
* ========================================================== */constRUNTIME='docsify'constHOSTNAME_WHITELIST=[self.location.hostname,'fonts.gstatic.com','fonts.googleapis.com','cdn.jsdelivr.net']// The Util Function to hack URLs of intercepted requests
constgetFixedUrl=(req)=>{varnow=Date.now()varurl=newURL(req.url)// 1. fixed http URL
// Just keep syncing with location.protocol
// fetch(httpURL) belongs to active mixed content.
// And fetch(httpRequest) is not supported yet.
url.protocol=self.location.protocol// 2. add query for caching-busting.
// Github Pages served with Cache-Control: max-age=600
// max-age on mutable content is error-prone, with SW life of bugs can even extend.
// Until cache mode of Fetch API landed, we have to workaround cache-busting with query string.
// Cache-Control-Bug: https://bugs.chromium.org/p/chromium/issues/detail?id=453190
if(url.hostname===self.location.hostname){url.search+=(url.search?'&':'?')+'cache-bust='+now}returnurl.href}/**
* @Lifecycle Activate
* New one activated when old isnt being used.
*
* waitUntil(): activating ====> activated
*/self.addEventListener('activate',event=>{event.waitUntil(self.clients.claim())})/**
* @Functional Fetch
* All network requests are being intercepted here.
*
* void respondWith(Promise<Response> r)
*/self.addEventListener('fetch',event=>{// Skip some of cross-origin requests, like those for Google Analytics.
if(HOSTNAME_WHITELIST.indexOf(newURL(event.request.url).hostname)>-1){// Stale-while-revalidate
// similar to HTTP's stale-while-revalidate: https://www.mnot.net/blog/2007/12/12/stale
// Upgrade from Jake's to Surma's: https://gist.github.com/surma/eb441223daaedf880801ad80006389f1
constcached=caches.match(event.request)constfixedUrl=getFixedUrl(event.request)constfetched=fetch(fixedUrl,{cache:'no-store'})constfetchedCopy=fetched.then(resp=>resp.clone())// Call respondWith() with whatever we get first.
// If the fetch fails (e.g disconnected), wait for the cache.
// If there’s nothing in cache, wait for the fetch.
// If neither yields a response, return offline pages.
event.respondWith(Promise.race([fetched.catch(_=>cached),cached]).then(resp=>resp||fetched).catch(_=>{/* eat any errors */}))// Update the cache with the version we fetched (only for ok status)
event.waitUntil(Promise.all([fetchedCopy,caches.open(RUNTIME)]).then(([response,cache])=>response.ok&&cache.put(event.request,response)).catch(_=>{/* eat any errors */}))}})