Hybrid properties don't work in the presence of future annotations

まず from __future__ import annotations を使った例を再現し、次に forward_reference_solver 周辺の graphene_sqlalchemy/converter.py と、610 行付近の forward reference の処理を調べます。プリミティブ型を返すハイブリッドプロパティが、フィールド定義を手動で指定しなくても機能することを確認し、モデルの forward reference については既存の動作が維持されることを確認します。

This has been driving me a bit nuts since the columns/hybrids refactor, and I haven't been able to figure out if it's something new, expected, or something I'm doing wrong. Here's the simplest scenario I could come up with to demonstrate it.

@declarative_mixin
@as_declarative()
class Base:
    pass

class Person(Base):
    __tablename__ = "person"

    id = Column(postgresql.UUID(as_uuid=True), primary_key=True)

    @hybrid_property
    def hello(self) -> str:
        return "world"

class GPerson(SQLAlchemyObjectType):
    class Meta:
        model = Person

class GQuery(ObjectType):
    person = Field(GPerson)

schema = Schema(query=GQuery)

I would expect this to work, and it does. It even works if I make my hello property return a list[list[str]] or something weird like that. But! If you import __future__ annotations, this scenario no longer works:

from __future__ import annotations

<the code from above>

Traceback (most recent call last):
  File "/home/vscode/.local/share/virtualenvs/bios-backend-rDkHOn2N/lib/python3.10/site-packages/graphql/type/definition.py", line 808, in fields
    fields = resolve_thunk(self._fields)
  File "/home/vscode/.local/share/virtualenvs/bios-backend-rDkHOn2N/lib/python3.10/site-packages/graphql/type/definition.py", line 300, in resolve_thunk
    return thunk() if callable(thunk) else thunk
  File "/home/vscode/.local/share/virtualenvs/bios-backend-rDkHOn2N/lib/python3.10/site-packages/graphene/types/schema.py", line 305, in create_fields_for_type
    field_type = create_graphql_type(field.type)
  File "/home/vscode/.local/share/virtualenvs/bios-backend-rDkHOn2N/lib/python3.10/site-packages/graphene/types/field.py", line 116, in type
    return get_type(self._type)
  File "/home/vscode/.local/share/virtualenvs/bios-backend-rDkHOn2N/lib/python3.10/site-packages/graphene/types/utils.py", line 42, in get_type
    return _type()
  File "/home/vscode/.local/share/virtualenvs/bios-backend-rDkHOn2N/lib/python3.10/site-packages/graphene_sqlalchemy/converter.py", line 615, in forward_reference_solver
    raise TypeError(
TypeError: No model found in Registry for forward reference for type ForwardRef('str'). Only forward references to other SQLAlchemy Models mapped to SQLAlchemyObjectTypes are allowed.

This is because with __future__ annotations, -> str creates a ForwardRef, and forward refs (unlike normal types) have to be SQLAlchemy models (https://github.com/graphql-python/graphene-sqlalchemy/blob/master/graphene_sqlalchemy/converter.py#L610). So you have to explicitly supply hybrid field definitions, even for methods that return simple primitive types. This is a huge inconvenience, as we have many of these kinds of computed properties in our codebase.

Any ideas if this is something fixable? Or are we just stuck with having to manually add field definitions everywhere?