Function preventSecondInstance

src/main/lifecycle/startup.ts:64–85

* Enforce a single application instance. If a second instance is launched, * any protocol URL in the command line is forwarded to the existing instance. * * @param mb - The menubar instance to show when a second instance is detected. * @param protocol - The custom protocol string to extract from

(mb: Menubar, protocol: string)

 * @param protocol - The custom protocol string to extract from command line args.
 */
function preventSecondInstance(mb: Menubar, protocol: string): void {
  const gotTheLock = app.requestSingleInstanceLock();

  if (!gotTheLock) {
    logWarn('main:gotTheLock', 'Second instance detected, quitting');
    app.quit();
    return;
  }

  app.on('second-instance', (_event, commandLine) => {
    logInfo(
      'main:second-instance',
      'Second instance was launched. Extracting command to forward',
    );

    const url = commandLine.find((arg) => arg.startsWith(`${protocol}://`));

    if (url) {
      handleProtocolURL(mb, url, protocol);
    }
  });
}