Can handle multiple errors using Nestjs' Exception Filter? - nestjs

Question

Spring boot was able to handle various errors using #RestControllerAdvice. The code created by spring boot is as follows.
#RestControllerAdvice
public class ControllerExceptionHandler {
// #valid에서 바인딩 에러가 발생
#ExceptionHandler(MethodArgumentNotValidException.class)
protected ResponseEntity<ErrorResponse> handleMethodArgumentNotValidException(MethodArgumentNotValidException e) {
log.error("handleMethodArgumentNotValidException ==> " + e);
final ErrorResponse response = ErrorResponse.of(ErrorCode.WRONG_INPUT_VALUE, e.getBindingResult());
return new ResponseEntity<>(response, HttpStatus.BAD_REQUEST);
}
// 사용자 생성시 이메일이 중복된 경우
#ExceptionHandler(DuplicateEmailException.class)
public ResponseEntity<ErrorResponse> handleDuplicateEmailException(DuplicateEmailException e) {
log.error("handleDuplicateEmailException ==> " + e);
final ErrorResponse response = ErrorResponse.of(ErrorCode.DUPLICATE_EMAIL_VALUE);
return new ResponseEntity<>(response, HttpStatus.BAD_REQUEST);
}
...
}
Currently, I was looking for features similar to #RestControllerAdvice while using NestJs to handle errors, and I found out about ExceptionFilter. I wrote the code, but I had a question after writing it. If we process the error like this, we can only process errors related to HttPexception, right?
I want to handle other errors globally besides HttPexception. However, unlike Spring Boot's #RestControllerAdvice, ExceptionFilter does not seem to be able to handle many errors in a single class. Am I using it wrong?
#Catch()
export class ExceptionHandler implements ExceptionFilter {
catch(exception: HttpException, host: ArgumentsHost) {
const ctx = host.switchToHttp();
const response = ctx.getResponse<Response>();
const request = ctx.getRequest<Request>();
const status = exception.getStatus();
response.status(status).json({
statusCode: status,
message: exception.message,
path: request.url
});
}
}

Answer 1

You have to pass exception class to #Catch() decorator.
If you want to catch all http exceptions you can do
import { ExceptionFilter, Catch } from '#nestjs/common';
#Catch(HttpException)
export class ExceptionHandler implements ExceptionFilter {
catch(exception: HttpException, host: ArgumentsHost) {
const ctx = host.switchToHttp();
const response = ctx.getResponse<Response>();
const request = ctx.getRequest<Request>();
const status = exception.getStatus();
response.status(status).json({
statusCode: status,
message: exception.message,
path: request.url
});
}
}
This will catch all errors thrown when executing any route.
You can also pass a few exception classes to catch only particular exceptions.
#Catch(BadRequestException, UnauthorizedException)
You can read more at https://docs.nestjs.com/exception-filters