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@jtbandes
Last active April 9, 2021 21:43
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SharedWorker fails to load from asar: https://github.com/electron/electron/issues/28572
node_modules
out
package-lock.json
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<!-- https://developer.mozilla.org/en-US/docs/Web/HTTP/CSP -->
<meta http-equiv="Content-Security-Policy" content="default-src 'self'; script-src 'self' blob: file: 'unsafe-inline'">
<meta http-equiv="X-Content-Security-Policy" content="default-src 'self'; script-src 'self' blob: file: 'unsafe-inline'">
<title>Hello World!</title>
</head>
<body>
<script src="./renderer.js"></script>
<p>
<button onclick="testWorker()">Create Worker with file: URL</button>
<button onclick="testSharedWorker()">Create SharedWorker with file: URL</button>
<button onclick="testSharedWorkerWorkaround()">Create SharedWorker with blob: URL</button>
</p>
<p>
<button onclick="preload.openDevTools()">Open main dev tools</button>
<button onclick="preload.inspectSharedWorker()">Open dev tools on SharedWorker</button>
</p>
</body>
</html>
// Modules to control application life and create native browser window
const {app, BrowserWindow} = require('electron')
const path = require('path')
function createWindow () {
// Create the browser window.
const mainWindow = new BrowserWindow({
width: 800,
height: 600,
webPreferences: {
preload: path.join(__dirname, 'preload.js')
}
})
// and load the index.html of the app.
mainWindow.loadFile('index.html')
mainWindow.webContents.openDevTools();
mainWindow.webContents.on('ipc-message', (event, channel) => {
if (channel === 'openDevTools') {
mainWindow.webContents.closeDevTools();
mainWindow.webContents.openDevTools();
} else {
mainWindow.webContents.closeDevTools();
mainWindow.webContents.inspectSharedWorker();
}
});
}
// This method will be called when Electron has finished
// initialization and is ready to create browser windows.
// Some APIs can only be used after this event occurs.
app.whenReady().then(() => {
createWindow()
app.on('activate', function () {
// On macOS it's common to re-create a window in the app when the
// dock icon is clicked and there are no other windows open.
if (BrowserWindow.getAllWindows().length === 0) createWindow()
})
})
// Quit when all windows are closed, except on macOS. There, it's common
// for applications and their menu bar to stay active until the user quits
// explicitly with Cmd + Q.
app.on('window-all-closed', function () {
if (process.platform !== 'darwin') app.quit()
})
// In this file you can include the rest of your app's specific main process
// code. You can also put them in separate files and require them here.
{
"name": "selfish-wave-summarize-n5lg9",
"productName": "selfish-wave-summarize-n5lg9",
"description": "My Electron application description",
"keywords": [],
"main": "./main.js",
"version": "1.0.0",
"author": "work",
"scripts": {
"start": "electron-forge start",
"package": "electron-forge package",
"make": "electron-forge make",
"publish": "electron-forge publish",
"lint": "echo \"No linting configured\""
},
"devDependencies": {
"@electron-forge/cli": "6.0.0-beta.52",
"@electron-forge/maker-deb": "6.0.0-beta.52",
"@electron-forge/maker-rpm": "6.0.0-beta.52",
"@electron-forge/maker-squirrel": "6.0.0-beta.52",
"@electron-forge/maker-zip": "6.0.0-beta.52",
"electron": "13.0.0-beta.8"
},
"config": {
"forge": {
"packagerConfig": {
"asar": true
},
"makers": [
{
"name": "@electron-forge/maker-squirrel"
},
{
"name": "@electron-forge/maker-zip",
"platforms": [
"darwin"
]
},
{
"name": "@electron-forge/maker-deb",
"config": {}
},
{
"name": "@electron-forge/maker-rpm",
"config": {}
}
]
}
}
}
// All of the Node.js APIs are available in the preload process.
// It has the same sandbox as a Chrome extension.
const {contextBridge, ipcRenderer} = require("electron");
window.addEventListener('DOMContentLoaded', () => {
const replaceText = (selector, text) => {
const element = document.getElementById(selector)
if (element) element.innerText = text
}
for (const type of ['chrome', 'node', 'electron']) {
replaceText(`${type}-version`, process.versions[type])
}
})
contextBridge.exposeInMainWorld('preload', {
openDevTools: () => ipcRenderer.send('openDevTools'),
inspectSharedWorker: () => ipcRenderer.send('inspectSharedWorker'),
})
// This file is required by the index.html file and will
// be executed in the renderer process for that window.
// No Node.js APIs are available in this process because
// `nodeIntegration` is turned off. Use `preload.js` to
// selectively enable features needed in the rendering
// process.
const h1 = document.createElement('h1');
h1.textContent = `Running from ASAR: ${JSON.stringify(window.location.href.includes(".asar/"))}`;
document.body.prepend(h1);
async function testWorker() {
const worker = new Worker('worker.js');
worker.onmessage = (e) => {
console.log('message from Worker:', e);
};
}
async function testSharedWorker() {
const worker = new SharedWorker('worker.js');
worker.onerror = (e) => {
console.log('SharedWorker error:', e);
};
worker.port.onmessage = (e) => {
console.log('Message from SharedWorker:', e);
};
worker.port.start();
}
async function testSharedWorkerWorkaround() {
const url = URL.createObjectURL(await (await fetch('worker.js')).blob());
const worker = new SharedWorker(url);
worker.onerror = (e) => {
console.log('SharedWorker error:', e);
};
worker.port.onmessage = (e) => {
console.log('Message from SharedWorker:', e);
};
worker.port.start();
}
function helperFunction() {
return 'A worker loaded a helper function!';
}
console.log('I am executing in a worker!');
if (self.postMessage) {
self.postMessage('You successfully launched a Worker');
importScripts('worker-helper.js');
self.postMessage(helperFunction());
}
if (typeof SharedWorkerGlobalScope !== 'undefined' && self instanceof SharedWorkerGlobalScope) {
self.onconnect = (e) => {
console.log('Connected');
e.ports[0].start();
e.ports[0].postMessage('You successfully launched a SharedWorker');
importScripts('worker-helper.js');
e.ports[0].postMessage(helperFunction());
};
}
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