Electron Installer

NPM module that builds Windows installers for Electron apps using Squirrel.

Installing

npm install --save-dev electron-winstaller

Usage

Require the package:

const electronInstaller = require('electron-winstaller');

Then do a build like so..

// NB: Use this syntax within an async function, Node does not have support for
//     top-level await as of Node 12.
try {
  await electronInstaller.createWindowsInstaller({
    appDirectory: '/tmp/build/my-app-64',
    outputDirectory: '/tmp/build/installer64',
    authors: 'My App Inc.',
    exe: 'myapp.exe'
  });
  console.log('It worked!');
} catch (e) {
  console.log(`No dice: ${e.message}`);
}

After running you will have an .nupkg, a RELEASES file, and a .exe installer file in the outputDirectory folder for each multi task target given under the config entry.

There are several configuration settings supported:

Sign your installer or else bad things will happen

For development / internal use, creating installers without a signature is okay, but for a production app you need to sign your application. Internet Explorer's SmartScreen filter will block your app from being downloaded, and many anti-virus vendors will consider your app as malware unless you obtain a valid cert.

Any certificate valid for "Authenticode Code Signing" will work here, but if you get the right kind of code certificate, you can also opt-in to Windows Error Reporting. This MSDN page has the latest links on where to get a WER-compatible certificate. The "Standard Code Signing" certificate is sufficient for this purpose.

Handling Squirrel Events

Squirrel will spawn your app with command line flags on first run, updates, and uninstalls. it is very important that your app handle these events as early as possible, and quit immediately after handling them. Squirrel will give your app a short amount of time (~15sec) to apply these operations and quit.

The electron-squirrel-startup module will handle the most common events for you, such as managing desktop shortcuts. Add the following to the top of your main.js and you're good to go:

if (require('electron-squirrel-startup')) return;

You should handle these events in your app's main entry point with something such as:

const app = require('app');

// this should be placed at top of main.js to handle setup events quickly
if (handleSquirrelEvent()) {
  // squirrel event handled and app will exit in 1000ms, so don't do anything else
  return;
}

function handleSquirrelEvent() {
  if (process.argv.length === 1) {
    return false;
  }

  const ChildProcess = require('child_process');
  const path = require('path');

  const appFolder = path.resolve(process.execPath, '..');
  const rootAtomFolder = path.resolve(appFolder, '..');
  const updateDotExe = path.resolve(path.join(rootAtomFolder, 'Update.exe'));
  const exeName = path.basename(process.execPath);

  const spawn = function(command, args) {
    let spawnedProcess, error;

    try {
      spawnedProcess = ChildProcess.spawn(command, args, {detached: true});
    } catch (error) {}

    return spawnedProcess;
  };

  const spawnUpdate = function(args) {
    return spawn(updateDotExe, args);
  };

  const squirrelEvent = process.argv[1];
  switch (squirrelEvent) {
    case '--squirrel-install':
    case '--squirrel-updated':
      // Optionally do things such as:
      // - Add your .exe to the PATH
      // - Write to the registry for things like file associations and
      //   explorer context menus

      // Install desktop and start menu shortcuts
      spawnUpdate(['--createShortcut', exeName]);

      setTimeout(app.quit, 1000);
      return true;

    case '--squirrel-uninstall':
      // Undo anything you did in the --squirrel-install and
      // --squirrel-updated handlers

      // Remove desktop and start menu shortcuts
      spawnUpdate(['--removeShortcut', exeName]);

      setTimeout(app.quit, 1000);
      return true;

    case '--squirrel-obsolete':
      // This is called on the outgoing version of your app before
      // we update to the new version - it's the opposite of
      // --squirrel-updated

      app.quit();
      return true;
  }
};

Notice that the first time the installer launches your app, your app will see a --squirrel-firstrun flag. This allows you to do things like showing up a splash screen or presenting a settings UI. Another thing to be aware of is that, since the app is spawned by squirrel and squirrel acquires a file lock during installation, you won't be able to successfully check for app updates till a few seconds later when squirrel releases the lock.

Debugging this package

You can get debug messages from this package by running with the environment variable DEBUG=electron-windows-installer:main e.g.

DEBUG=electron-windows-installer:main node tasks/electron-winstaller.js