How to describe polymorphic endpoint

We use Spring+Jackson(Java). And in our API we can send different object to same endpoint. For example

  @JsonTypeInfo(
      use = JsonTypeInfo.Id.NAME, 
      include = As.PROPERTY, 
      property = "type")
    @JsonSubTypes({
        @JsonSubTypes.Type(value = Dog.class, name = "dog"),
        @JsonSubTypes.Type(value = Cat.class, name = "cat")
    })
    public static class Animal {
    }
 
    @JsonTypeName("dog")
    public static class Dog extends Animal {
        public double barkVolume;
    }
 
    @JsonTypeName("cat")
    public static class Cat extends Animal {
        boolean likesCream;
        public int lives;
    }

@Controller
public class MyController {

    //REST service
    @RequestMapping( value = "test")
    public  @ResponseBody String save(@RequestBody  Animal animal){
        System.out.println(animal.getClass());
        return success;
    }
}

Sending to /test

{
    "type": "dog",
    "barkVolume": 23.3
}

will show Dog.class

Sending to /test

{
    "type": "cat",
    "likesCream": true,
    "lives": 42
}

will show Cat.class

How to describe polymorphic endpoint in Swagger?

[frantuma]

thanks @SabhtarshaMojo , it was indeed a bug, fixed in #3293

[SabhtarshaMojo]

Hit a NPE when my model had some required fields but did not have the discriminatorProperty as part of the class definition. Could fix it by changing the code here: https://github.com/swagger-api/swagger-core/blob/6c702f1e5d5842d1abdcf5ba664f54ca615cd202/modules/swagger-core/src/main/java/io/swagger/v3/core/jackson/ModelResolver.java#L1643

Changed the condition to following and it fixed it, if (modelToUpdate.getRequired() == null || !modelToUpdate.getRequired().contains(typeInfoProp)) {