Generate preload cache from live app

ts/scripts/generate-preload-cache.ts

@@ -1,35 +1,51 @@
 // Copyright 2024 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
-import { pathToFileURL } from 'node:url';
+import { spawnSync } from 'node:child_process';
 import { join } from 'node:path';
-import { app, BrowserWindow, ipcMain } from 'electron';
+import { tmpdir } from 'node:os';
+import { mkdtemp, rm } from 'node:fs/promises';
 
-app.on('ready', async () => {
-  ipcMain.handle('done', () => {
-    app.quit();
-  });
+const ROOT_DIR = join(__dirname, '..', '..');
 
-  ipcMain.handle('error', (_event, err) => {
-    console.error(err);
-    process.exit(1);
-  });
+const ELECTRON = join(
+  ROOT_DIR,
+  'node_modules',
+  '.bin',
+  process.platform === 'win32' ? 'electron.cmd' : 'electron'
+);
 
-  const window = new BrowserWindow({
-    show: false,
-    webPreferences: {
-      devTools: true,
-      nodeIntegration: false,
-      sandbox: false,
-      contextIsolation: true,
-      preload: join(__dirname, 'generate-preload-cache.preload.js'),
-    },
-  });
+async function main(): Promise<void> {
+  const storagePath = await mkdtemp(join(tmpdir(), 'signal-preload-cache-'));
 
-  await window.loadURL(
-    pathToFileURL(join(__dirname, 'generate-preload-cache.html')).toString()
-  );
+  let status: number | null;
+  try {
+    ({ status } = spawnSync(
+      ELECTRON,
+      ['--js-args="--predictable --random-seed 1"', 'ci.js'],
+      {
+        cwd: ROOT_DIR,
+        env: {
+          ...process.env,
+          GENERATE_PRELOAD_CACHE: 'on',
+          SIGNAL_CI_CONFIG: JSON.stringify({
+            storagePath,
+          }),
+        },
+        // Since we run `.cmd` file on Windows - use shell
+        shell: process.platform === 'win32',
+      }
+    ));
+  } finally {
+    await rm(storagePath, { recursive: true });
+  }
 
-  window.webContents.openDevTools();
-  window.webContents.send('compile', process.argv[2], process.argv[3]);
+  if (status !== 0) {
+    throw new Error(`Exit code: ${status}`);
+  }
+}
+
+main().catch(error => {
+  console.error(error);
+  process.exit(1);
 });