Node.js process.exit cleanup

nodejs-clean-exit.ts

function emitExit(signal: string) {
  const exitCode = 0;
  console.log(`Received "${signal}" signal. Will terminate with exit code "${exitCode}".`);
  process.exit(exitCode);
}

// Catches Ctrl + C events
process.on('SIGINT', () => emitExit('SIGINT'));

// Catches "kill pid" events (for example: nodemon restarts)
process.on('SIGUSR1', () => emitExit('SIGUSR1'));
process.on('SIGUSR2', () => emitExit('SIGUSR2'));

// Catches unhandled errors
process.on('uncaughtException', error => {
  console.log('Unhandled error.', error);
  process.exit(1);
});

// Catches unhandled Promise rejections
process.on('unhandledRejection', error => {
  console.log('Unhandled Promise rejection.', error);
  process.exit(1);
});

// `process.exit` callback
process.on('exit', (code: number) => {
  console.log(`App exits with code "${code}". Synchronous cleanup can be done here.`);
});