This article will tell you how to support pwa on docsify.

1.Requirements

All stations support https ,it is the premise of support pwa.

There are too many tutorials to enable https online ,so this article is not in the narrative.

2.Create and register manifest.json

Web App Manifest - Users can add your site to mobile home screen.

Ⅰ.Create manifest.json in the root directory

Example:

manifest.json

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{
"name": "Linux Notes - 我的Linux笔记",
"short_name": "Linux Notes",
"icons": [
{
"src": "img/icons/icon_144x144.png",
"sizes": "144x144",
"type": "image/png"
},
{
"src": "img/icons/icon_152x152.png",
"sizes": "152x152",
"type": "image/png"
},
{
"src": "img/icons/icon_192x192.png",
"sizes": "192x192",
"type": "image/png"
},
{
"src": "img/icons/icon_256x256.png",
"sizes": "256x256",
"type": "image/png"
}
],
"start_url": "/",
"display": "standalone",
"background_color": "#fff",
"theme_color": "#fff"
}

Ⅱ.Register manifest.json in your index.html.

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<!-- pwa manifest.json -->
<link rel="manifest" href="./manifest.json">

2.Create and register sw.js

Service Worker - Make your site available offline.

Ⅰ.Create sw.js in the root directory

Example:

sw.js

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/* ===========================================================
* docsify sw.js
* ===========================================================
* Copyright 2016 @huxpro
* Licensed under Apache 2.0
* Register service worker.
* ========================================================== */

const RUNTIME = 'docsify'
const HOSTNAME_WHITELIST = [
self.location.hostname,
'fonts.gstatic.com',
'fonts.googleapis.com',
'unpkg.com'
]

// The Util Function to hack URLs of intercepted requests
const getFixedUrl = (req) => {
var now = Date.now()
var url = new URL(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
}
return url.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(new URL(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
const cached = caches.match(event.request)
const fixedUrl = getFixedUrl(event.request)
const fetched = fetch(fixedUrl, { cache: 'no-store' })
const fetchedCopy = 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 */ })
)
}
})

Ⅱ.Register sw.js in your index.html.

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<script>
if (typeof navigator.serviceWorker !== 'undefined') {
navigator.serviceWorker.register('sw.js')
}
</script>

4.References

Offline Mode(PWA) - docsify