[SOLVED] howto handle array and object as response to the same rest endpoint

howto handle array and object as response to the same rest endpoint

I'm integrating with REST API which can return sometimes an object and sometimes an array to the same REST endpoint for example

HTTP 401 with body
{
    "code": "_AUTHENTICATION",
    "message": "Authentication failure: Unauthenticated.",
    "report": false,
    "extended": null
}

and

HTTP 200 with body
[
     ["01K9TP7BQK03104V13CLPA0XD","error accepting record"]
]

My question is how to handle this on client side?
Im using WebClient, java 17 and its a Spring Boot app.
My request is this:

Mono<EventResponse> response = webClient
  .post()
  .uri(apiUrl)
  .contentType(MediaType.APPLICATION_JSON)
  .bodyValue(body)
  .retrieve()
  .bodyToMono(EventResponse.class);

where EventResponse I can map to either object or array returned by this API. For now it looks like this:

@Getter
@Setter
@EqualsAndHashCode
@ToString
public class EventResponse {

    private String code;
    private String message;
    private boolean report;
    private String extended;
}

when the API returns an array I have an understable excption

Cannot deserialize value of type `....EventResponse` from Array value...

Solution

See the @ControllerAdvice . In your endpoint, you send the valid case. For the other problem, you throw an error and handle with the controller advice.