Arg regex in Field Class not work, and Type Literal not supported

[leokyler]

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Example Code

from typing import Annotated, Literal
from sqlmodel import Field, SQLModel
from pydantic import AfterValidator

ROLES_SET = {"student", "teacher", "admin"}


def check_role(x: str):
    assert x in ROLES_SET, f"role must be in {'student', 'teacher', 'admin'}"
    return x

class UserBase(SQLModel):
    role: Annotated[str, AfterValidator(check_role)]  # worked
    # role: Literal["student", "teacher", "admin"] # when use it with fastapi,the User class will trigger error.
    # role: Annotated[str, Field(regex=r'^(student|teacher|admin)$')]  #no error,but not work,and string can pass

class User(UserBase, table=True):
    id: int | None = Field(default=None, primary_key=True)

Description

In my code, I write two class extend from SQLmodel.

Attr 'role'（str） in class should in ["student", "teacher", "admin"].
In the normal python /pydantic class system, I can use role: Literal["student", "teacher", "admin"]。
But when I set it in a class extend SQLmodel, I get error:

File "/home/leo/myspace/collaborative_learning_system/server/models/tables.py", line 76, in
class User(UserBase, table=True):
File "/home/leo/myspace/collaborative_learning_system/server/venv/lib/python3.12/site-packages/sqlmodel/main.py", line 559, in new
col = get_column_from_field(v)
^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/leo/myspace/collaborative_learning_system/server/venv/lib/python3.12/site-packages/sqlmodel/main.py", line 708, in get_column_from_field
sa_type = get_sqlalchemy_type(field)
^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/leo/myspace/collaborative_learning_system/server/venv/lib/python3.12/site-packages/sqlmodel/main.py", line 656, in get_sqlalchemy_type
if issubclass(type_, Enum):
^^^^^^^^^^^^^^^^^^^^^^^
TypeError: issubclass() arg 1 must be a class

As a substitute, I think maybe can use role: Annotated[str, Field(regex=r'^(student|teacher|admin)$')] ,but when I use it with fastapi, I found any string can be inserted into the database(postgresql).
In addition,I found regex in the Field from pydantic can work! If use it, the code like:
role: Annotated[str, Field(partten=r'^(student|teacher|admin)$')]

Final, I have to use: Annotated[str, AfterValidator(check_role)], it can work ,but not simple and not grace.

Operating System

Linux

Operating System Details

ubuntu23 (wsl)

SQLModel Version

0.0.22

Python Version

python3.12.3

Additional Context

[YuriiMotov]

This is a duplicate of #735 (regex) and #57 (Literal).

I'll close this discussion. Let's track these issues there