Support inheritance when generating TS interfaces

[guaycuru]

Currently if I have

class ChildClass(ParentClass):
  something: str

class ParentClass(BaseModel):
  anything: str

The generated output is:

export interface ChildClass {
  something: string;
  anything: string;
}

export interface ParentClass {
  anything: string;
}

When a better output would be:

export interface ChildClass extends ParentClass {
  something: string;
}

export interface ParentClass {
  anything: string;
}

It seems https://github.com/bcherny/json-schema-to-typescript supports this. See this example.

[phillipdupuis]

This is a good question/thought. But I don't think there is a solution, or at least not a simple one :(

This open issue (pydantic/pydantic#8161) seems to be about the same problem, albeit with allOf rather than extends. And it does not sound like it's going to be implemented by pydantic any time soon.

Will need to think on this

Maybe if you had a custom schema generator function with a check like

if a parent exists:
    add the parent ref via "extends" or "allOf"
    then iterate through "properties" for both parent and child, deleting from "child" if the definition is unchanged

[guaycuru]

Yeah, I have a somewhat working proptotype, but I keep running into edge cases.
It's on the back burner for now as work has been crazy lately.