ruoyi-plus-soybean/public/streamsaver/sw.js

133 lines
3.7 KiB
JavaScript

/* eslint-disable */
/* global self ReadableStream Response */
self.addEventListener('install', () => {
self.skipWaiting();
});
self.addEventListener('activate', event => {
event.waitUntil(self.clients.claim());
});
const map = new Map();
// This should be called once per download
// Each event has a dataChannel that the data will be piped through
self.onmessage = event => {
// We send a heartbeat every x second to keep the
// service worker alive if a transferable stream is not sent
if (event.data === 'ping') {
return;
}
const data = event.data;
const downloadUrl =
data.url || `${self.registration.scope + Math.random()}/${typeof data === 'string' ? data : data.filename}`;
const port = event.ports[0];
const metadata = Array.from({ length: 3 }); // [stream, data, port]
metadata[1] = data;
metadata[2] = port;
// Note to self:
// old streamsaver v1.2.0 might still use `readableStream`...
// but v2.0.0 will always transfer the stream through MessageChannel #94
if (event.data.readableStream) {
metadata[0] = event.data.readableStream;
} else if (event.data.transferringReadable) {
port.onmessage = evt => {
port.onmessage = null;
metadata[0] = evt.data.readableStream;
};
} else {
metadata[0] = createStream(port);
}
map.set(downloadUrl, metadata);
port.postMessage({ download: downloadUrl });
};
function createStream(port) {
// ReadableStream is only supported by chrome 52
return new ReadableStream({
start(controller) {
// When we receive data on the messageChannel, we write
port.onmessage = ({ data }) => {
if (data === 'end') {
return controller.close();
}
if (data === 'abort') {
controller.error('Aborted the download');
return;
}
controller.enqueue(data);
};
},
cancel(reason) {
console.log('user aborted', reason);
port.postMessage({ abort: true });
}
});
}
self.onfetch = event => {
const url = event.request.url;
// this only works for Firefox
if (url.endsWith('/ping')) {
return event.respondWith(new Response('pong'));
}
const hijacke = map.get(url);
if (!hijacke) return null;
const [stream, data, port] = hijacke;
map.delete(url);
// Not comfortable letting any user control all headers
// so we only copy over the length & disposition
const responseHeaders = new Headers({
'Content-Type': 'application/octet-stream; charset=utf-8',
// To be on the safe side, The link can be opened in a iframe.
// but octet-stream should stop it.
'Content-Security-Policy': "default-src 'none'",
'X-Content-Security-Policy': "default-src 'none'",
'X-WebKit-CSP': "default-src 'none'",
'X-XSS-Protection': '1; mode=block',
'Cross-Origin-Embedder-Policy': 'require-corp'
});
const headers = new Headers(data.headers || {});
if (headers.has('Content-Length')) {
responseHeaders.set('Content-Length', headers.get('Content-Length'));
}
if (headers.has('Content-Disposition')) {
responseHeaders.set('Content-Disposition', headers.get('Content-Disposition'));
}
// data, data.filename and size should not be used anymore
if (data.size) {
console.warn('Depricated');
responseHeaders.set('Content-Length', data.size);
}
let fileName = typeof data === 'string' ? data : data.filename;
if (fileName) {
console.warn('Depricated');
// Make filename RFC5987 compatible
fileName = encodeURIComponent(fileName).replace(/['()]/g, escape).replace(/\*/g, '%2A');
responseHeaders.set('Content-Disposition', `attachment; filename*=UTF-8''${fileName}`);
}
event.respondWith(new Response(stream, { headers: responseHeaders }));
port.postMessage({ debug: 'Download started' });
};