Globally set the response content schema for specific status codes

[jochenberger]

We have a lot of methods that return a specific type of object, e.g.

@ApiResponse(
      responseCode = "200",
      description = "Person loaded")
  @ApiResponse(
      responseCode = "404",
      description = "Person not found",
      content =
          @Content(
              mediaType = MediaType.APPLICATION_JSON_VALUE,
              schema = @Schema(implementation = ErrorResponse.class)))
  @GetMapping("/{uuid}")
  public Person getPerson(

Now everywhere I want to document the 404 (or any other error) response, I need to specify the content schema ErrorResponse, or otherwise, Person ends up as the content schema for the 404 response.
Is it possible to define that mapping application-wide so I don't have to repeat it in so many places?

[jochenberger]

I may just have found a solution myself:

@Bean
  public OperationCustomizer errorResponseSchemas(
      final SpringDocConfigProperties springDocConfigProperties) {
    Schema schema =
        AnnotationsUtils.resolveSchemaFromType(
            ErrorResponse.class, null, null, springDocConfigProperties.isOpenapi31());
    Content content =
        new Content()
            .addMediaType(
                org.springframework.http.MediaType.APPLICATION_JSON_VALUE,
                new MediaType().schema(schema));
    return (operation, handlerMethod) -> {
      operation
          .getResponses()
          .forEach(
              (status, response) -> {
                if (HttpStatus.resolve(Integer.valueOf(status)).is4xxClientError()) {
                  response.setContent(content);
                }
              });
      return operation;
    };
  }

Is this how it's supposed to be done? Is this the correct way to get hold of the Schema instance?

[Mattias-Sehlstedt]

There are also other ways of realizing it. If you are using a ControllerAdvice then that should be able to lead to response documentation (if your controller advice is configured correctly).

It should also be possible to realize it by for example creating a Controller-interface that all of your controllers implement, and that that interface then is annotated with your @ApiResponse(responseCode = "404", ...) documentation.