LitJSON VS JsonSubTypes

I think JSON is used reasonably often under the hood for various things in Unity, I certainly use it in all my games. The builtin JSONUtility can do the job, but there are some edge cases (serializing lists without a base class, for example) where it falls over. LitJSON is a simple but comprehensive option if you need more power.

If messages are arriving as Json you can use JsonSubTypes to deserialize to different DTOs based on the UUIDs (https://github.com/manuc66/JsonSubTypes) and then use the visitor pattern to dispatch the DTOs to the correct method.

Personally I've had good success with JsonSubTypes for deserializing discriminated unions from JSON. It'll serialize stuff into the right type, and then you just need a switch statement to typecast it afterwards.

There is a small use case that I consider valid for this. It would be for determining a set of pre-defined behaviors to make available to definitions of entities in a game. And the json data would not be coming from external sources, it would be tightly controlled by me as the developer. The response you made to the other comment on my post shared a link that said the practice shouldn't be done with untrusted data, and there would be no untrusted data since there'd be no external data. The article also mentions to restrict the types that can be deserialized, and that is definitely possible. The architecture pattern for this is ECS (Entity Component System) and the data-drive portion might have been a mis-naming of my post, it's more of a lot of the design of entities and components is stored in data files, and there are a few cases where I will want to associate certain functionality in the code with these data entity definitions. No operating system level functionality would be exposed. I've even been referred to a library available via nuget that will allow for what I'm attempting to do: https://github.com/manuc66/JsonSubTypes