stylus/dist/js/worker-util.js
2021-12-12 21:32:50 +08:00

90 lines
2.0 KiB
JavaScript

'use strict';
/* exported createWorker */
function createWorker({url, lifeTime = 300}) {
let worker;
let id;
let timer;
const pendingResponse = new Map();
return new Proxy({}, {
get(target, prop) {
return (...args) => {
if (!worker) init();
return invoke(prop, args);
};
},
});
function init() {
id = 0;
worker = new Worker('/js/worker-util.js?' + new URLSearchParams({url}));
worker.onmessage = onMessage;
}
function uninit() {
worker.onmessage = null;
worker.terminate();
worker = null;
}
function onMessage({data: {id, data, error}}) {
pendingResponse.get(id)[error ? 'reject' : 'resolve'](data);
pendingResponse.delete(id);
if (!pendingResponse.size && lifeTime >= 0) {
timer = setTimeout(uninit, lifeTime * 1000);
}
}
function invoke(action, args) {
return new Promise((resolve, reject) => {
pendingResponse.set(id, {resolve, reject});
clearTimeout(timer);
worker.postMessage({id, action, args});
id++;
});
}
}
/* exported createWorkerApi */
function createWorkerApi(methods) {
self.onmessage = async ({data: {id, action, args}}) => {
let data, error;
try {
data = await methods[action](...args);
} catch (err) {
error = true;
data = cloneError(err);
}
self.postMessage({id, data, error});
};
}
function cloneError(err) {
return Object.assign({
name: err.name,
stack: err.stack,
message: err.message,
lineNumber: err.lineNumber,
columnNumber: err.columnNumber,
fileName: err.fileName,
}, err);
}
if (self.WorkerGlobalScope) {
const loadedUrls = [];
self.require = urls => {
const toLoad = (Array.isArray(urls) ? urls : [urls])
.map(u => u.endsWith('.js') ? u : u + '.js')
.filter(u => !loadedUrls.includes(u));
if (toLoad) {
loadedUrls.push(...toLoad);
importScripts(...toLoad);
}
};
const url = new URLSearchParams(location.search).get('url');
if (url) require(url);
}