Generate FastAPI docs from msgspec.Struct json schema about msgspec

[provinzkraut]

The answer here is, unfortunately, that FastAPI simply does not support this for types that are not natively supported by Pydantic. There's not much that can be done from msgspec's side here, as it's a design decision/constraint on FastAPI's side.

[kemingy]

I'm also using msgspec in a micro-service to validate the requests and generate the OpenAPI doc. I build a simple tool defspec to generate the OpenAPI schema and render it with Swagger/Redoc/Scalar.