spring boot - How to map and log exceptions but still have SpringBoot render the JSON response?

Question

I want a global exception handler that

a) maps certain exceptions to HTTP response codes, maybe by translating e.g. NoSuchElementException to ResponseStatusException

b) adds logging depending on the exception, e.g. NullPointerException gets more verbose logging than NoSuchElementExceptions

c) uses the SpringBoot JSON error response i.e. { timestamp: ..., status: ..., error: ... }

I read

• https://www.baeldung.com/exception-handling-for-rest-with-spring and
• https://docs.spring.io/spring-framework/docs/current/reference/html/web.html#mvc-exceptionhandlers

but most approaches, like @ExceptionHandler want me to provide the HTTP response body. I want to use the original SpringBoot JSON error message though which is probably made by the DefaultErrorAttributes class.

Any ideas?

question from:https://stackoverflow.com/questions/65598409/how-to-map-and-log-exceptions-but-still-have-springboot-render-the-json-response

Answer 1

I finally figured out that the obvious solution with @ExceptionHandler does indeed work but I had to add server.error.message: always to get the exception message into the response as well! (the default is ok as it can contain sensitive information!)

Apart from that it looks like:

@RestControllerAdvice
class ExceptionHandlers {

   @ExceptionHandler
   fun handleAllErrors(e: Throwable, response: HttpServletResponse) {
      ...
      response.sendError(status, message)
   }
}