NestJS: Hit default endpoint when 404 (endpoint not found)

Question

I'd like to create some sort of catch all endpoint that will account for different request types: Get, Post, Options, etc. and also any request. Something like the following:

@CatchAll('*')
public notFound {
  return 'Endpoint not found';
}

Does anything like this exist in NestJS?

Answer 1

By default if you request an endpoint that doesn't exist NestJS will return a 404 response with a payload similar to the following:

{
    "statusCode": 404,
    "message": "Cannot GET /your-endpoint",
    "error": "Not Found"
}

I don't know about the specific use case, but if you want, it is possible to create a custom exception filter that will catch everything (or a specific error you want to throw). You can create a custom filter by implementing ExceptionFilter and check the error type to return a custom payload

@Catch()
export class AllExceptionsFilter implements ExceptionFilter {
  constructor(private readonly httpAdapterHost: HttpAdapterHost) {}

  catch(exception: unknown, host: ArgumentsHost): void {

    const ctx = host.switchToHttp();

    // check the httpStatus code and add custom logic if you want
    const httpStatus =
      exception instanceof HttpException
        ? exception.getStatus()
        : HttpStatus.INTERNAL_SERVER_ERROR;

    const responseBody = {
       // ... your custom response body
    };

    this.httpAdapterHost.httpAdapter.reply(ctx.getResponse(), responseBody, httpStatus);
  }
}

And enable the exception filter as global in your main.ts file

const http_adapter = app.get(HttpAdapterHost);
app.useGlobalFilters(new AllExceptionsFilter(http_adapter));