iOS: JsonSerializationException: Cannot deserialize readonly or fixed size dictionary: System.Collections.Generic.IReadOnlyDictionary

[Zorrendor]

Having exception with serialization metadata on iOS, works in Unity Editor and Android.

Unity 2022.3.14f
Managed stripping level: Minimal

I believe the issue is with stripping backend which is il2cpp for iOS and Mono for Android. Somehow, on iOS doesn't support serialization of:

        [Preserve]
        [JsonProperty("metadata")]
        public IReadOnlyDictionary<string, string> Metadata { get; }

Tried to pass null, empty Dictionary, both didn't work

[StephenHodgson]

Try adding a link.xml with the missing types

[StephenHodgson]

https://docs.unity3d.com/Manual/ManagedCodeStripping.html

[StephenHodgson]

If you can figure out which type is missing I'll add it to the package link.xml

[Zorrendor]

Thank you Stephen for fast response. Yes, I tried different types, the whole OpenAI namespace, it didn't work out. I think the issue is not with stripping but with deserialization IReadOnlyDictionary itself. It can't deserialise metadata but somehow works fine on Android.
I will try to make a build for Android with il2cpp and check if the issue reproduces.

[StephenHodgson]

It would not reproduce because I use this in my production build that's in the app store

[StephenHodgson]

I'm unfamiliar with iOS but it definitely seems as though a type is getting stripped from the build somehow.

Let me know what you can find and I'll implement a fix if possible.

[Zorrendor]

I've just built for Android with il2cpp setting and having the same deserialization exception with IReadOnlyDictionary metadata.
Mono works without issues.

Could you please try to build for Android or other platform with il2cpp scripting backend and to check if you can reproduce the issue?

[StephenHodgson]

Yes I build for il2cpp Android daily.

Since I don't use the assistants API in my production builds just yet I'll have to probably write up something and double check this specific thing. It could be maybe the deserialized type is incorrect.

[kripper10]

I am having the same issue when building to Quest device (Android, APK)
The weird thing is that it works fine when I run directly on PC but not on Quest,
I updated to 7.1.1 but still seems to be an issue.