Inheritance + Swagger UI + Model Example help

Hi,

When using Swagger UI I am unable to get the Example Value to properly generate an example that contains the derived classes in the example.

    [JsonConverter(typeof(EntityCustomJsonConverter))]
    [KnownType(typeof(CompanyRequestModel))]
    [KnownType(typeof(PersonRequestModel))]
    public abstract class PartyBaseRequestModel : BaseObjectRequestModel
    {
        public EntityEnums.Parties.Role[] Roles { get; set; }
    }

This BaseEntityCustomJsonConverter<T> is used on a custom ModelBinding for my incoming request to determine (from the EntityType property we ask in our request) which Object to case the jObject too.

public sealed class EntityCustomJsonConverter : BaseEntityCustomJsonConverter<BaseObjectRequestModel>
    {
        private const string EntityTypeKey = "EntityType";

        protected override BaseObjectRequestModel Create(Type objectType, JObject jsonObject)
        {
            if (!jsonObject.TryGetValue(EntityTypeKey, StringComparison.InvariantCultureIgnoreCase, out var entityType))
            {
                return default;
            }

            switch (entityType.ToString().ToLowerInvariant())
            {
                case EntityTypes.Parties.Person:
                    return jsonObject.ToObject<PersonRequestModel>();
                case EntityTypes.Parties.Company:
                    return jsonObject.ToObject<CompanyRequestModel>();
                default:
                    throw new NotSupportedException();
            }
        }
    }

    {
        protected abstract T Create(Type objectType, JObject jsonObject);
        public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
        {
            throw new NotImplementedException();
        }

        public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
        {
            var jsonObject = JObject.Load(reader);
            var target = Create(objectType, jsonObject);
            if (target != null)
            {
                serializer.Populate(jsonObject.CreateReader(), target);
            }

            return target;
        }

        public override bool CanConvert(Type objectType)
        {
            return typeof(T).GetTypeInfo().IsAssignableFrom(objectType.GetTypeInfo());
        }
    }

Image of partial Model Example:

Swagger UI see’s my inherited class in the Model’s according:

What I would actually like to see in Swagger UI is this: (This image was taken from a YAML file created by me for another API that we will create, hence the different properties - What I like achieve does not change though)

Notice how “nodes” property contains an AnyOf with a list of models. How can I achieve this through code?

[wesley-pattison]

Well, I feel a bit silly. I never changed my SchemaType to OpenApi 3.0 - Only this supports the anyOf keyword.

With this code:

            if (context.Type.Name is nameof(PartyBaseRequestModel) || context.Type.Name is nameof(BaseObjectRequestModel))
            {
                var attributes = context.Type.GetCustomAttributes(typeof(KnownTypeAttribute), true) as Attribute[];
                foreach (var attribute1 in attributes)
                {
                    var attribute = (KnownTypeAttribute) attribute1;
                    var schema = await context.Generator.GenerateWithReferenceAsync<JsonSchema4>(attribute.Type, attributes, context.Resolver,
                        async (p, s) => {});
                    context.Schema.AnyOf.Add(schema);
                }

                context.Schema.Properties.Clear();
                context.Schema.AllowAdditionalProperties = true;
            }

and the settings:

                settings.GeneratorSettings.FlattenInheritanceHierarchy = true;
                settings.GeneratorSettings.SchemaType = SchemaType.OpenApi3;
                settings.GeneratorSettings.SchemaProcessors.Add(new KnownTypeSchemaProcessor());

I was able to achieve:

Thanks for support! 👍

[RicoSuter]

Related PR: https://github.com/RSuter/NJsonSchema/pull/733