Help needed! sqlalchemy.exc.InvalidRequestError: When initializing mapper Mapper[User(user)], expression "relationship('list[RefreshToken]')" seems to be using a generic class

[M4RC0Sx]

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Example Code

# user_model.py
from __future__ import annotations

import uuid

from typing import TYPE_CHECKING

from pydantic import EmailStr  # noqa: TC002
from sqlmodel import Field
from sqlmodel import Relationship
from sqlmodel import SQLModel


if TYPE_CHECKING:
    from my_app.models.token_model import RefreshToken


class UserBase(SQLModel):
    email: EmailStr = Field(unique=True, index=True, max_length=255)
    is_active: bool = Field(default=True)
    is_superuser: bool = Field(default=False)
    full_name: str | None = Field(default=None, max_length=255)


class UserCreate(UserBase):
    password: str = Field(min_length=8, max_length=128)


class UserUpdate(SQLModel):
    email: EmailStr | None = None
    full_name: str | None = None
    is_active: bool | None = None
    is_superuser: bool | None = None
    password: str | None = None


class UserUpdateMe(SQLModel):
    full_name: str | None = None
    email: EmailStr | None = None


class UserUpdatePasswordMe(SQLModel):
    current_password: str = Field(min_length=8, max_length=128)
    new_password: str = Field(min_length=8, max_length=128)


class User(UserBase, table=True):
    id: uuid.UUID = Field(default_factory=uuid.uuid4, primary_key=True)
    hashed_password: str = Field()
    refresh_tokens: list[RefreshToken] = Relationship(
        back_populates="user", cascade_delete=True
    )


class UserPublic(UserBase):
    id: uuid.UUID


class UsersPublic(SQLModel):
    data: list[UserPublic] = Field(default_factory=list)
    count: int = Field(default=0)





# token_model.py
from __future__ import annotations

import uuid  # noqa: TC003

from datetime import datetime  # noqa: TC003
from typing import TYPE_CHECKING

from sqlmodel import Field
from sqlmodel import Relationship
from sqlmodel import SQLModel


if TYPE_CHECKING:
    from my_app.models.user_model import User


class TokenPayload(SQLModel):
    sub: str | None = None


class Token(SQLModel):
    access_token: str
    refresh_token: str
    token_type: str = "bearer"


class RefreshToken(SQLModel, table=True):
    id: int | None = Field(default=None, primary_key=True)
    token: str = Field(index=True, unique=True)
    user_id: uuid.UUID = Field(foreign_key="user.id")
    expires_at: datetime

    user: User = Relationship(back_populates="refresh_tokens")

Description

I am trying to make a user 1-t relation with refreshtokens. I have followed the example of SQLModel but when I start the app I get this error:

sqlalchemy.exc.InvalidRequestError: When initializing mapper Mapper[User(user)], expression "relationship('list[RefreshToken]')" seems to be using a generic class as the argument to relationship(); please state the generic argument using an annotation, e.g. "refresh_tokens: Mapped[list['RefreshToken']] = relationship()"

I have tried to add the Mapped, remove type_checking block, rebuild the model... None of them has worked.

Operating System

Linux

Operating System Details

No response

SQLModel Version

0.0.24

Python Version

Python 3.13.5

Additional Context

No response

[YuriiMotov]

There is a known issue with from __future__ import annotations.
Try removing it (use refresh_tokens: list["UserPublic"] and user: "User")