Replace @PathVariable object with ID only for Springdoc

I am currently trying to migrate from Springfox to Springdoc.

Most of my endpoints contain a @PathVariable Instance. Obviously I am only passing in the ID of the instance and Spring would automatically resolve the object for me.

Here is an example:

@RestController
@RequestMapping(value = "/api/{instance}/role")
public class RoleController {

  @GetMapping()
  public ResponseEntity<?> getRoles(@PathVariable Instance instance) {
    return ResponseEntity.ok().build();
  }
  
}

Called as /api/myInstance/role.

Springfox would handle this correctly for me, only generating {instance} as a String mapping to the ID of Instance. However, Springdoc expects the entire object to be passed as a path param.

I did try this so far, however it didn’t seem to have any effect:

static {
  SpringDocUtils.getConfig().replaceParameterObjectWithClass(Instance.class, String.class);
}

If possible, I’d like to avoid annotating hundreds of endpoints with the same annotation and solve this on a global level.

Answer

You can define your own ParameterCustomizer:

@Component
public class InstanceParameterCustomizer implements org.springdoc.core.customizers.ParameterCustomizer {
    @Override
    public Parameter customize(Parameter parameterModel, MethodParameter methodParameter) {
        if (Instance.class.equals(methodParameter.getParameterType()) && methodParameter.getParameterAnnotation(PathVariable.class) != null) {
            parameterModel.setName("id"); // if you need to change the name  ...
            parameterModel.setSchema(new StringSchema());
        }
        return parameterModel;
    }
}