[NestJS] Fallback Exception Filter

Fallback exception filter is mean to catch any exception which are not catched by other exception filters;

import { Catch, ExceptionFilter, ArgumentsHost } from "@nestjs/common";

@Catch()
export class FallbackExpectionFilter implements ExceptionFilter {
    catch(exception: any, host: ArgumentsHost) {
        console.log('fallback exception handler triggered',
        JSON.stringify(exception));

        const ctx = host.switchToHttp();
        const response = ctx.getResponse();

        return response.status(500)
            .json({
                statusCode: 500,
                createdBy: "FallbackExceptionFilter",
                errorMessage: exception.message ? exception.message: 'Unexpected error ocurred';
            });
    }
}

 

main.ts:

import { NestFactory } from '@nestjs/core';

import { AppModule } from './app.module';
import { HttpExceptionFilter } from './filters/http-exception.filter';
import { FallbackExpectionFilter } from './filters/fallback.filter';

async function bootstrap() {
  const app = await NestFactory.create(AppModule);

  app.setGlobalPrefix('api');
  app.useGlobalFilters(
    new FallbackExpectionFilter(),
    new HttpExceptionFilter(),
  );

  await app.listen(9000);
}

bootstrap();

Order matters, from most generic to specific.