remoteview
Version:
Remote isolated browser platform by Dosyago
154 lines (130 loc) • 4.1 kB
JavaScript
// constants
const CACHE = "lw-cache-20190614";
const CLEAR = location.search.startsWith('?v=CLEAR');
const ONLINE_TEST = location.protocol + '//' + location.hostname + '/online-test.html';
// route
const IGNORE = {
[ONLINE_TEST]: true
};
const NEVER_CACHE = {
'/api/v1/tabs': true,
};
const API_STUB = {
'/api/v1/tabs' : async () => new Response(
JSON.stringify({ tabs: [], requestId: 0 }),
{
status:200,
statusText:'OK',
headers: {
'Content-Type': 'application/json'
}
}
)
};
const OFFLINE = async () => new Response(
NoLoadView(),
{
status:200,
statusText:'OK',
headers: {
'Content-Type': 'text/html'
}
}
);
// handlers
self.addEventListener('activate', async e => await e.waitUntil(self.Clients.claim()));
self.addEventListener('install', async e => {
try {
await e.skipWaiting();
} finally {
await setup();
}
});
self.addEventListener('fetch', e => e.waitUntil(fetchResponder(e)));
async function fetchResponder(e) {
CLEAR && console.log(e.request);
if ( e.request.method != 'GET' ) return;
if ( e.request.url in IGNORE ) return;
const Url = new URL(e.request.url);
if ( Url.port !== location.port ) return;
if ( Url.pathname.startsWith('/current') ) return;
e.respondWith(fetchResponder2(e));
}
async function fetchResponder2(e) {
const cache = await caches.open(CACHE);
const cachedResponse = await cache.match(e.request);
let response;
if (!CLEAR && cachedResponse) response = cachedResponse;
else if (e.request.cache === 'only-if-cached' && e.request.mode !== 'same-origin') return;
else response = await cacheFetcher2(e);
if ( response ) {
return response;
}
}
async function cacheFetcher2(e) {
const requestUrl = new URL(e.request.url);
const route = requestUrl.pathname;
let response;
try {
response = await fetch(e.request);
} catch(e) {
console.warn(e, e.request);
}
if ( response ) {
if ( route in NEVER_CACHE ) {
return response;
} else {
const clone = response.clone();
const cache = await caches.open(CACHE);
await cache.put(e.request, clone);
return response;
}
} else if ( route in API_STUB ) {
return API_STUB[route]();
} else {
return OFFLINE();
}
}
async function setup() {
await caches.open(CACHE);
}
// views
function NoLoadView() {
return `
<!DOCTYPE html>
<meta charset=utf-8>
<meta name=viewport content="width=device-width, initial-scale=1.0">
<title>We'll be right back</title>
<main>
<header>
<h1>Alakazam — we've vanished!</h1>
</header>
<article>
<h2>No doubt we shall return presently</h2>
<p>
As we see it, you have a couple of options right now:
</p>
<ul>
<li>
You can sit here and wait.
<li>
You can <a href=${self.registration.scope}>reload the page.</a>
<li>
You can <a href=https://github.com/dosycorp/service-issues/issues>open an issue.</a>
<li>
You can vent your anger into this <a href=#black-hole>black hole</a> below.
</ul>
<form id=black-hole>
<fieldset>Vent into the black hole</fieldset>
<p>
<textarea></textarea>
<p>
<button>Send into black hole</button>
</form>
</article>
<footer>
A production of <a target=_blank href=https://dosyago.com>The Dosyago Corporation</a>.
</footer>
</main>
`;
}