Handling nodejs errors in a NestJS application using a telegram bot as an example

import { Logger } from '@nestjs/common'; const logger = new Logger('Application'); //do something when app is closing process.on('exit', exitHandler.bind(null, { cleanup: true })); //catches ctrl+c event process.on('SIGINT', exitHandler.bind(null, { exit: true })); // catches "kill pid" (for example: nodemon restart) process.on('SIGUSR1', exitHandler.bind(null, { exit: true })); process.on('SIGUSR2', exitHandler.bind(null, { exit: true })); //catches uncaught exceptions process.on('uncaughtException', exitHandler.bind(null, { exit: true })); import { NestFactory } from '@nestjs/core'; import env from 'env-var'; import { AppModule } from './app/app.module'; async function bootstrap() { const app = await NestFactory.create(AppModule); const globalPrefix = 'api'; app.setGlobalPrefix(globalPrefix); const port = env.get('PORT').default(3333).asPortNumber(); await app.listen(port); logger.log( `🚀 Application is running on: http://localhost:${port}/${globalPrefix}` ); } try { bootstrap().catch((err) => { logger.error(err, err.stack); }); } catch (err) { logger.error(err, err.stack); } function exitHandler(options, exitCode) { if (options.cleanup) { logger.log('exit: clean'); } if (exitCode || exitCode === 0) { if (exitCode !== 0) { logger.error(exitCode, exitCode.stack); } else { logger.log(`exit: code - ${exitCode}`); } } if (options.exit) { process.exit(); } }